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Grapes and pomegranates are under attack by grape mealybugs.
Grape mealybug description Grape mealybugs (Pseudococcus maritimus) are small, white, flat-bodied plant suckers that appear to have a fringed skirt. Grape mealybug lifecycle These pests have two generations each year. Eggs and crawlers overwinter under bark and in crevices. In spring, they emerge and begin converging on young shoots, where they start to feed. Those early risers then return to the safety of the bark, where they lay more eggs. Damage caused by grape mealybugs Clustered grape mealybugs can open Pandora’s box to fruit rot and other diseases. How to manage grape mealybugs Natural predators, such as the predaceous gall midge (Dicrodiplosis californica) and the little brown mealybug destroyer (Scymnobius sordidus) can keep these pests under control, so avoid broad spectrum pesticides. If chemical treatments are absolutely necessary, Applaud has been found effective.  Western conifer seed bug (Didier Descouens) CC BY-SA 4.0 Native to North America west of the Rocky Mountains, Western conifer seed bugs (Leptoglossus occidentalis) have recently expanded their range to the East Coast and are occasionally found in Europe. Western conifer seed bug description These narrow, shield-shaped insects are brown and average 3/4 to 1” in length. They have the classic tags seen on the rear legs of all leaf-footed bugs and their antennae tend to stick out on either side. Eggs are brown. Nymphs have light-colored legs and look much like assassin bigs, until they start filling out. Conifer seed bug lifecycle Adult female conifer seed bugs lay 200 eggs in rows, usually along needles, leaf midribs, or stems of host plants. In spring, the eggs hatch and nymphs go through five developmental stages, or instars, before reaching adulthood. In North America, there is only one generation a year, but two or more generations have been seen in Mexico and southern Europe.  Western conifer seed bug as seen through a window (BMRR) CC BY-SA 3.0 Conifer seed bug damage These pests generally feed on the sap of developing conifer cones, causing the seeds within to distort and wither. Favored trees include lodgepole pine, white spruce, and Douglas-firs, though red pine, mountain pine, European black pine, Scots pine, and even pistachios are sometimes chosen. They can also vomit up digestive juices that soften hard seeds. I just hope they never find my stone pine! Even worse, conifer seed bugs have been found to use their piercing mouthparts to damage PEX tubing. PEX tubing is similar to PVC and is used to insulate high voltage electrical wires, and to transport offshore oil and natural gas, sewage, and chemicals.  Western conifer seed bug found on summery savory (Kate Russell) Insecticides are not recommended, though they can be used as a last resort against heavy nymph infestations. It is better to avoid using broad spectrum insecticides. Provide pollen and water for natural predators. Some tachinid flies have been known to parasitize conifer seed bug eggs. Spiders, assassin bugs, and birds also feed on conifer seed bugs.
European fruit lecanium scale might be a long name, but these garden pests can make short work of your pomegranates, citrus, and olives.  European fruit lecanium scale (IPM Images) CC BY-SA 3.0 European fruit lecanium scale description
European fruit lecanium scale is a soft scale insect. This means the shiny brown convex cover is not as hard as armored scale covers. You can identify European fruit lecanium scales because the brown cover has several ridges on it, while other soft scale insects do not. European fruit lecanium scale lifecycle European fruit lecanium scale larvae are normally found on twigs and small branches. As temperatures begin to rise in spring, they develop the telltale dome-shaped cover. Adult females fill the space under their cover with eggs and then they die. When the eggs hatch, the nymphs, or crawlers, come out from underneath the scale covers and hide out on the underside of leaves. By late July or August, these pests migrate to fruit. There can be two generations each year and most of the insects present will be in the same life stage. Damage caused by European fruit lecanium scale When European fruit lecanium scale larvae feed, they attach themselves to the outside of twigs and fruit and pierce the surface. This causes cosmetic damage as well as providing points of entry for other pests and diseases. Also, European fruit lecanium scale feeding results in the excretion of honeydew (sugary bug poop), which sooty mold fungi find delightful. The only exception is that scale feeding on pomegranates does not result in honeydew deposits. Instead, tiny piles of sugar are seen. These sugar piles are easily brushed off of twigs and fruit. European fruit lecanium scale controls Natural enemies are the best controls for European fruit lecanium scale. Twicestabbed lady beetles, steel blue lady beetles, and lacewings will all help fight soft scales. You can also wrap tree trunks with sticky barriers to remove the protection (and disease-carrying potential) provided by ants. Finally, prune trees for good air flow and structure to keep trees healthy. Adult cigarette beetles only live for a few weeks and do not eat. They can, however, fly. And cigarette beetle larvae are surprisingly destructive.  Cigarette beetle (Andybrookestar, Public Domain) Cigarette beetles (Lasioderma serricorne) favor tobacco plants. But they will also go after cereal grains, dried fruit, and these popular garden plants: Cigarette beetles will also feed on spices, including paprika, cumin, and sage. You may also find them in your flour, pet food, and even your favorite books! Cigarette beetle description These tiny brown beetles look almost identical to furniture and drugstore beetles, with a more humpbacked profile. If you use a hand lens, you can see that cigarette beetles have distinctive clubs at the ends of their antennae. Cigarette beetles are tiny. Eight of them could stand, end-to-end, across a dime. But don’t let their diminutive size fool you.  Cigarette beetle, multiple views (Kamran Iftikhar) CC BY-SA 3.0 Cigarette beetle lifecycle
Adult female cigarette beetles lay 30 to 100 eggs in and around preferred foods. As soon as the larvae hatch, they start feeding and moving around. After feeding and pooping, larvae enter a pupal stage in cocoons made from the foods they infested, making them difficult to see. While insecticides are effective against cigarette beetles, you are better off tossing out infested materials. Vacuuming and pheromone traps can also help control these tiny pests. You’ve probably read dozens of articles and posts about the wonders of dish soap as a pesticide, fungicide, and surfactant in the garden. All of those posts are wrong.
How dish soap works
Dish soap is a detergent. Dish soap cleans dishes by cutting grease, oil, and wax. Dish soap generally contains colorants, fragrances, bleach, enzymes, phosphates, and rinsing agents. None of those are good for your plants. Dish soap damages protective, waxy coatings used by plants and insects. If you wash this protective coating away, infection, infestation, and dehydration become more likely. Dish soap v. insecticidal soap Insecticidal soap is not a detergent. It is a soap specifically formulated for use on plants. It must be used properly to be safe and effective. While liquid hand soap is a soap and not a detergent, it contains fatty acids that are phytotoxic (poisonous to plants). Despite popular opinion, dish soap does not belong in the garden. Save it for your dishes, and your plants will thank you. You won’t see them, but fig mites can bring serious diseases to your figs.
Fig mites (Eriophyes ficus, also known as Aceria fici) are a type of eriophyid mite and they are found worldwide. Fig mite description Adult fig mites are pale yellow, wedge-shaped, and have two pairs of legs near the head, but they are extremely small. Even with a 20x hand lens, these mites are difficult to see. Larvae look something like a fat plant hair that moves. At only 1/250” long, the only way you will know they are present is by using a microscope or looking for signs of the damage they cause. Damage caused by fig mites Fig mites often infest young leaves and bud scales. Fig mite feeding causes russeting, most commonly seen on the underside of leaves and on the bottom of figs. Russeting transforms smooth, healthy tissue into rough, brown, dry tissue. Fig mite feeding also results in fruit and leaf drop and twig stunting. The real problem with fig mites is that they can carry and transmit fig mosaic. Trees infected with fig mosaic should be removed, so it is worth the effort. Fig mite control Monitor leaves for signs of mite feeding from late spring through summer. If fig mites are seen, apply sulfur or horticultural oils, depending on the time of year. [Oils can burn leaves in summer.] I have also seen anecdotal recommendations for the use of spinosad against fig mites, but I do not know how effective it is. Swatting at a yellow jacket is never a good idea. Rather than chasing them off, you can easily cause them to give an alarm, triggering the attack of several hundred yellow jackets. So, who invited them to the picnic?  German wasp (Fir0002/Flagstaffotos) GFDL 1.2 Yellow jackets (or yellowjackets) are omnivorous social wasps and they can be a royal pain at outdoor summer events. Not only can yellow jackets be annoying, as they feed on your burgers and cupcakes, they can sting and bite at the same time! Unlike honey bees, which lose their stingers (and die) after a single sting, yellow jacket stingers do not have barbs and can be used repeatedly and with great prejudice. The more you know about yellow jackets, the better you can protect yourself and your family from painful stings. Yellow jacket identification Yellow jackets are frequently confused with bees and other wasps. Unlike stubby, brown honey bees, which are covered with short hairs, yellow jackets appear more smooth-bodied and shiny. Beneficial mud daubers have a very narrow waist and build their nests out of mud and paper wasps build small, umbrella-shaped nests with exposed cells. Mud daubers and paper wasps generally do not eat human food and are rarely aggressive unless provoked.
Aside from being unique in their high level of aggression, yellow jackets are generally medium-sized black wasps with jagged bands of yellow or white on the abdomen. While yellow jackets have the classic wasp-waist, it is often not clearly visible.
There are several different species of yellow jackets found in North America:
You may be able to identify a yellow jacket from a distance by its tendency to fly side-to-side as it prepares to land. And if you ever see white grubs coming out of a wasp nest, it means that the adults have been unable to provide for their larvae, who are now in search for food on their own. Often, it is easier to identify a yellow jacket by its nest.
Yellow jacket nests
Yellow jackets make their nests by scraping up wood fibers and mixing them with saliva. These nests look like fat, paper footballs when you can see them, but sometimes you can’t. Yellow jackets can be divided into ground-nesting and aerial nesting varieties. Aerial-nesting yellow jackets build the familiar rounded, hanging nests with a single entry hole at the base. While aerial-nesting wasps are generally not aggressive, they will attack if you get too close to their nest. Ground-nesting yellow jackets, on the other hand, are extremely aggressive and you might not see them until it’s too late. Ground-nesting yellow jackets frequently build their nests in rodent burrows, rotted tree cavities, and houses. Apparently, to a yellow jacket, the space between the interior and exterior walls of your house make the perfect site for a nest that can contain up to 15,000 wasps. If you see a yellow jacket, it is safe to assume that there is a yellow jacket nest no more than 1/4 mile away. Seasonal wasp aggression Yellow jackets are particularly aggressive when it comes to protecting their nest. Yellow jackets are also likely to sting while out foraging for food. The aggressiveness of yellow jackets changes with the seasons. In spring, yellow jackets are busy building their nest and providing larvae with protein, usually in the form of insects. As summer progresses and the colony population increases, their need for protein decreases and sugary foods, needed by the queen and her workers, are in greater demand. This is also when many resources start becoming more scarce and wasp aggressiveness becomes more of a problem. By late summer and autumn, yellow jackets are best described as angry scavengers. This is when they end up at your picnics and cookouts. They are also seen around pet food, trash cans, and around fruit trees, where overripe fruit provides easy access to sugar. Preventing yellow jacket stings If you are eating outside, the best way to prevent stings is to keep food and sugary drinks in sealed containers. This is especially true for canned soft drinks that contain sugar, as a wasp may go in the can and then sting your mouth when you take a drink. Once yellow jackets have found a food source, they will pester the area long after the food is gone. One popular method at reducing yellow jacket stings is to toss a piece of raw meat and a sugary food away from the area before unpacking the rest of the food. If yellow jackets discover this food source first, they may be less likely to become a problem at your picnic. I don’t know if it actually works, but it sounds good. Working in the yard, one of the best ways to prevent stings is to be alert. Before digging, always look for ground-nesting wasps. I once was chased into my house by a swarm of very angry stinging insects when I tried to plant an apricot tree in my front yard. It is far better to be on the lookout before a confrontation occurs. If you do get stung, read my post on wasps for treatment tips. Yellow jacket control Lure traps placed around your property line are effective control measures against yellow jackets. You can buy yellow jacket lures at garden centers and many home improvement stores, as well as online. Most of these lures use a chemical called heptyl butyrate. This attractant works well on western yellow jackets, but not so well on other yellow jacket species. You can improve the effectiveness of yellow jacket lure traps by adding a small piece of raw meat to the trap. This will be especially effective on German yellow jackets. Just be sure to replace the meat frequently, as wasps are not attracted to rotting meat. Newer bait traps, those using esfenvalerate, have not been shown to be effective. If you know the location of a yellow jacket nest, there are nest sprays that can kill the colony. Before you start spraying, you need to know that wasps will attack when they sense the poison being sprayed. While these poisons are effective, you should be sure to wear protective clothing and keep your distance while using the spray. Nighttime applications are significantly safer, but there is no guarantee. Plus, it may take a day or so for all the wasps to die and the remaining wasps are going to be very angry. Consider yourself warned. Has a largish beetle with stripes ever hissed at you? It was probably a ten-lined June beetle. Ten-lined June beetles (Polyphylla decemlineata), also known as watermelon beetles, can kill mature trees outright.  Male ten-lined June beetle (Amanda Townsend) CC BY-SA 3.0 Ten-lined June beetle description The stripes are a giveaway for this relatively large beetle. Averaging 1.5 inches or longer, male ten-lined June beetles have distinctive antennae made up of overlapping scales, called lamellate plates. When these pests feel threatened, those plates are closed up and air is forced between the back and wings to create a hissing sound. Adult females do not fly. Eggs are 1/16" long, oval and cream-colored. Larvae have a white body and a brown head. They can grow to 2” in length with 3 pairs of legs.  Male ten-lined June beetle (Junkyardsparkle) CC0 Damage caused by ten-lined June beetles Almond, apple, cherry, and plum trees are susceptible to damage caused by larval feeding of ten-lined June beetles. Trees may simply not thrive, at first. By the time the damage is significant, it is usually too late to save the tree. Adult ten-lined beetles feed on leaves, but that damage is insignificant.
 Ten-lined June beetle open (Amanda Townsend) CC BY-SA 3.0 Ten-lined June beetle controls
Heavily infested trees must be removed and the surrounding soil fumigated to prevent infestation of nearby trees. Luckily, that is rarely necessary in a home garden. Because female ten-lined beetles do not fly, populations spread slowly. Commercial growers use soil insecticides to kill beetles in the larval stage. Aboveground insecticides are not effective. Tachinid flies parasitize these pests, but not significantly. Because male ten-lined June beetles are attracted to light, you can capture them on your porch with a butterfly net and feed them to your chickens, or simply squish them whenever you see them. Bulb mites, also known as spinach crown mites, refer to a small collection of very tiny pests that can damage your onions, garlic, saffron crocus, and spinach plants.
Bulb mite description Bulb mites are a collection of pests from the Rhizoglyphus and Tyrophagus genus and they look like miniature ticks with spiky hairs. These pests may be tiny, but they can cause significant damage. Ranging in size from 1/2 to 1 mm long, you could 15 to 30 or more of them nose-to-tail across a dime. If you were to look at one with a magnifying glass, you would see that they are a shiny, creamy white, with four pairs of brown legs. Bulb mite host plants As the name implies, bulb mites infest bulbs, such as tulips, daffodils, and saffron crocus. They can also be found under the root plate of garlic and onion, or in the crown of spinach plants. Damage caused by bud mites Bud mite feeding is not particularly destructive by itself. The problem lies in the wounds created by that feeding. These damaged areas allow organisms responsible for decomposition to get inside your plants, causing them to rot. Overall stunting, leaf distortion, and softened stems are common responses to bud mite feeding. How to manage bulb mites Protect your bulbs against bulb mites by inspecting them before planting. Infested bulbs should be destroyed. Crop rotation and the removal of post-harvest plant debris can interrupt this pest’s lifecycle. You don't have to grow corn to have a reason to worry about seed corn maggots.  Seed corn maggot flies (Martin Cooper) CC BY 2.0 Seed corn maggots mostly feed on decaying organic material, but sometimes they feed on the roots and seeds of over 50 different garden plants. Also known as the bean seed fly, seed corn maggots may be tiny, but they can ruin several of your crops.
Seed corn maggot description Seed corn maggots (Delia platura) are small, dark gray flies with gray wings, black legs, three stripes on the back, and scattered bristles. Less than 1/4” long, seed corn maggot adults looks nearly identical to onion maggot flies. White or off-white larvae are legless and have rounded tails and pointed heads. Pupal cases are brown and hard and look like skinny footballs. Seed corn maggot damage Seed corn maggots often feed on the seeds of corn, peas, beans, and soybeans but they do not always kill the embryos within the seeds. When those seeds germinate, they are spindly and rarely make it to maturity, wasting valuable resources. Other crops commonly attacked by seed corn maggots include cucumbers, melons, onions, peppers, and potatoes. Seed corn maggots may tunnel into the stems and roots of many different garden plants and feed on spinach leaves, often providing points of entry for other pests and diseases. Seed corn maggot lifecycle Adult flies emerge in spring and begin feeding on nectar and honeydew. After mating, females lay an average of 270 eggs in the soil, near the surface. One week later, larvae emerge and begin feeding. One to three weeks later, larvae move back into the soil where they pupate for one to three weeks, or over the winter. How to control corn seed maggots The key to controlling corn seed maggots is in the soil. While I am a proponent of no-dig gardening, repeated appearances of corn seed maggots warrants disturbing the top 2 or 3 inches of soil on a regular basis during the spring and summer months. Research is being conducted on the possibility of beneficial fungi being used to control these pests, but it is not currently an option. As is nearly always the case, prevention is far easier. You can reduce the odds of seed corn maggots attacking your crops by waiting for the weather to warm up before planting, and spacing plants properly. Anything that slows germination or initial seedling growth makes it easier for seed corn maggots.  Currant sawfly larvae (I, Karon ind) CC BY-SA 3.0 Currants make delicious jellies, pies, sauces, and even wine, but currant sawfly larvae can completely strip the leaves from your currant plants in only a few days. Also known as imported currantworms and common gooseberry sawflies, these pests feed on gooseberries and other members of the Ribes family. Native to Europe, this pest is now found throughout North America.
Like other sawflies, adult currant sawflies look like a cross between a wasp and a fly. The larvae grow to 3” in length, but their coloration makes them difficult to see. They start out green with black heads. As they grow, they develop yellowish ends and black spots.
Currant sawfly lifecycle Adult currant sawflies lay tiny, oval white eggs on the underside of leaves and there can be three generations each year. The first brood emerges after the first leaves appear in spring, the second occurs in early summer, and a third generation may occur, weather permitting. In each generation, feeding is very heavy and rapid. To make matters worse, feeding often begins on the lower, inner reaches of the shrub, so you may not even notice the damage right away. Be sure to inspect plants regularly for signs of feeding and look on the underside of leaves for eggs. How to control currant sawflies Before you take any drastic measures, you need to know that the larval stages of currant sawflies look a lot like little green caterpillars. The distinction is important because control measures are different for moth and sawfly larvae. Take a closer look. If you have one, grab a hand lens or magnifying glass. If if you see 6 or more pairs of hookless legs, it’s a sawfly. Caterpillars have tiny hooks on their stubby legs and they usually have only 3 pairs of prolegs. You can treat moth larvae infestations with Bacillus thuringiensis (Bt). That treatment will not work against sawflies. Commercial growers spray plants with Malathion as soon as currant sawflies appear. Your best choice for controlling currant sawflies is to spray infested plants with insecticidal soap and handpick currantworms as they are seen. While it might be cute to picture a fly buzzing around with a tiny saw, there is nothing to love about sawflies. _larvae.jpg) Sawfly larvae (Charles J Sharp) CC BY-SA 4.0 Sawflies get their name because their ovipositor (egg-laying organ) is shaped like a saw and used to cut notches into plants for egg-laying. Sawfly description Sawfly larvae may look like caterpillars or slugs, but these pests are in the same order as bees, wasps, and ants, and are closely related to woodwasps and horntails. You can tell the difference between sawfly larvae and caterpillars by counting their legs. Caterpillars usually have five or fewer prolegs on their abdomen, while sawfly larvae, such as the California pear sawfly, have 7 or 8 pairs of prolegs on their abdomen and 3 more pair on the thorax. With over 8,000 sawfly species, spread out over 800 genera, there is a wide variety of coloration and body type in the world of sawflies. As a group, their soft bodies are stubby and only slightly wasp-like, and they tend to be weak flyers. The ovipositor is often mistaken for a stinger, though sawflies cannot sting. Some sawfly larvae, however, are known to puke up a noxious liquid that would-be predators find distasteful, while other sawfly species raise their rear ends up, cobra-fashion, weaving back and forth a warning. Sawfly species Some of the more common sawfly species include:
Sawfly lifecycle Adult sawflies only live for one week, during which time they mate and females lay 30 to 90 eggs. Eggs are tan, oval or kidney-shaped, and look like tiny blisters on the upper surfaces of leaves. In 2 - 8 weeks, depending on temperatures, those eggs hatch and then go through 5 or 6 larval stages, depending on the species, before heading to the soil, en masse, to pupate. Some sawfly species use webspinning and leafrolling to protect their young, while others spin cocoons. The entire process can take 2 years. It is during the larval stages when sawflies do the most damage. Sawfly damage Sawflies are defoliators, which means they strip the leaves from several garden plants. Species tend to be host-specific. Rose sawflies attack roses, pine sawflies attack pine trees, and so on. Plants vulnerable to sawfly feeding include apple, cherry, peach, pear, plum, and quince trees, along with most cane fruits. Larvae often feed in large groups, for added protection. Damage caused by larval forms of sawflies include leafmining, defoliation, skeletonizing, galls, and notching of leaves.  Gall formed by willow leaf sawfly (James Lindsey) CC BY-SA 3.0 Sawfly controls
Generally speaking, handpicking is your best method of controlling sawfly larvae. You can feed them to your chickens for a tasty protein treat, or bag them and toss them in the trash. While Bacillus thuringiensis (Bt) can be used to control moth and butterfly larvae, it is not effective against sawfly larvae. Insecticides can be used against sawflies, but sawfly larvae are a popular food for many native birds, including partridges, black grouse, corn buntings, and chestnut-backed chickadees. Shrews, lizards and frogs also enjoy snacking on these pests, along with several predatory wasps, including ichneumon and braconid wasps. You can attract these garden helpers by providing fresh water, growing a variety of insectary plants and plants that provide pollen and nectar, and avoiding the use of broad spectrum pesticides and herbicides. Blue-green sharpshooters are sap-sucking, disease-carrying cousins of leafhoppers. Native to California, blue-green sharpshooters (Graphocephala atropunctata) have only recently become serious pests.  Blue -green sharpshooter with mites (Katja Schulz) CC BY 2.0 As blue-green sharpshooters feed, they inject plants with a bacteria that causes Pierce’s disease.
Pierce’s disease Pierce’s disease primarily affects grapes, but it can also appear on alfalfa, almond, avocado, blackberry, citrus, elderberry, and olive. The bacteria that cause Pierce’s disease block the flow of water and nutrients through the xylem, causing scorching, stunting, bleaching, leaf stippling, “matchstick” petioles, ‘green islands’ on stems, raisined grapes, defoliation and dieback. But symptoms do not always appear in the year the plant is infected. This results in many more plants becoming infected as sharpshooters move from plant to plant as they feed. Plants infected the previous year often exhibit delayed or absent budbreak. Plants infected early in the growing season are more likely to look as though they have recovered, even though they haven’t. There is no cure for Pierce’s disease and infected plants usually die within 1 to 3 years. Other diseases caused by the same bacteria include almond leaf scorch, oleander leaf scorch, and olive leaf scorch. These bacteria can also be carried by spittlebugs and glassy-winged sharpshooters. Outbreaks of Pierce’s disease have been growing dramatically. This is believed to be due to warmer temperatures allowing vectors, such as blue-green sharpshooters, and the bacteria they carry, to live through the winter. Blue-green sharpshooter description Unlike glassy-winged sharpshooters, which average 1/2” in length, blue-green sharpshooters are much smaller and easy to miss. As far as pests go, the blue-green sharpshooter is quite colorful. From a distance, it simply looks like a wedge-shaped green insect. If you look closely, with a hand lens, you suddenly see striking bright blue to green wings, thorax, and head, with a yellow abdomen and legs. There are sometimes red, yellow, or green markings. You may also be able to see red drops of sap attached to their legs. Blue-green sharpshooter lifecycle Until recently, only one generation of blue-green sharpshooter appeared each year. Rising temperatures and stressed predator insects are making multiple generations possible. Most sharpshooters overwinter near creeks, becoming active in spring. Eggs are laid just after budbreak. As surrounding vegetation begins to dry up, concentrations of sharpshooters in gardens, vineyards, and orchards increases. Sharpshooters go through complete metamorphosis, frequently leaving pale discarded exoskeletons behind on the underside of leaves. Nymphs and adults feed on nutrient-rich sap throughout the summer, moving back into nearby weeds and vegetation at the end of summer. Blue-green sharpshooters use vocalization to communicate and to find a mate. Males have 3 distinct calls: a complex mating call, a gulping call, and a chirping call. Females have a call they use to respond to males’ mating calls. The pair sings a type of duet before mating, which is all very nice, but they still spread disease. Because there is no cure for Pierce’s disease, interrupting the disease cycle is the only way to prevent plant loss. Controlling blue-green sharpshooters The first step to controlling blue-green sharpshooters is to make sure they are present. This is done with yellow sticky sheets. Sharpshooters are most commonly found in locations with abundant soil moisture and some shade. Unshaded, dry areas and areas of deep shade are less likely habitats for sharpshooters. You can reduce the chance of infection of Pierce’s disease with these tips:
Famers have found that installing bluebird boxes goes a long way toward reducing blue-green sharpshooter populations. Insecticides aimed at sharpshooters are only marginally effective, while insecticidal soap and horticultural oil provide some control. Since people first started growing plants for food, we have been battling the pests that eat, damage, or infect those plants.  Integrated Pest Management (Santa Fe Parks & Rec) Initially, those battles were hand-to-hand combat. Pests were removed by hand, chased away, and puzzled over. Then came the age of ‘better living through chemistry’, when powerful concoctions were sprayed willy-nilly, threatening entire species. Now, the pendulum has swung in a new, more balanced direction. That direction is called integrated pest management. Integrated pest management (IPM) is a program of science-based pest controls with the minimal disruption of natural cycles and least harm to other organisms. Integrated pest management was made a national policy in the U.S. by President Nixon in 1972. What are pests? Your younger brother or sister may have been a pest when you were kids, but garden pests never outgrow the potential to cause damage. Garden pests include any organism that can harm or hinder the plants we want to grow. Using this definition, a pest can be disease-carrying bacteria, viruses, or fungi, a plant-eating insect or animal, a competitive weed, destructive soil nematodes, or a neighbor’s cat that thinks your carrot patch is its litter box.  Tomato hornworm (Kate Russell) What is IPM? IPM takes a long view on reducing the negative impact of pests in ways that are sustainable and responsible. An integrated pest management plan has six basic tenets:
Rather than relying on a single method of control, IPM combines these tenets, in the order presented, to reduce the negative impacts associated with killing off pretty much anything. Rather than spraying chemical pesticides and insecticides on your food plants and into the soil and water table, you can work your way through these sustainable practices for surprisingly effective control of most garden pests. Monitoring for pests The first step in an IPM program is monitoring. Monitoring involves more than simply looking for bugs. Monitoring for problems begins by arming yourself with factual information about your soil and microclimate. This means sending out a sample for a soil test. Test results will let you know which nutrients are at acceptable, toxic, of deficient levels, along with soil pH, soil organic matter levels, and base saturations. It also means noting sun and wind exposure levels at various locations in your yard, the likelihood of frost damage, drainage problems, and preexisting pest problems. Each of these conditions play powerful roles in keeping plants healthy enough to defend themselves against pests. After collecting all that information, go outside and start looking for pests. You don’t know what you are up against without looking. You can use pheromone traps and yellow sticky sheets to help collect information of what costs are present. As you see pests, learn to identify them and then read up on them. Learn enough about them to counteract the damage they do without causing undo damage of your own. This is where things like trap crops come in handy.  Monitor pests with yellow sticky sheets Tolerable levels The next step is to decide just how much damage you are comfortable with. Wiping out entire species is generally not a good plan. Evolution takes time and the balances that are created can be delicate and easily thrown out of whack. Allowing tolerable levels of pests to be present provides food for beneficial insects which will help you fight the battle against those and others pests. Cultural practices Cultural practices are the way you manage your garden. Do you use overhead watering, which can encourage fungal disease, or do you use soaker hoses? Pruning for proper air flow and good structure go a long way toward pest control. There are several good cultural practices that help your plants stay healthy:
Mechanical controls The third plan of action is mechanical controls. Row covers, tree cages, tomato cages, netting, sticky barriers, brassica collars, mulch, shade cloth, tree supports, trellising, and fencing are common mechanical controls that help plants stay healthy. This stage of pest control also includes trapping, hand picking, and soil solarization. Cold frames, greenhouses, and hoophouses also provide mechanical controls that reduce pest damage by making life harder for the pests.  Praying mantid Biological controls There is an army of beneficial insects ready to help you control pests naturally, if you will only get out of their way. Instead of using chemical pesticides and insecticides, which can kill off beneficial predators and parasites, install insectary plants and provide water to create a welcome habitat for the natural enemies of the pests in your landscape.
Chemical pesticides are used as a last resort. Pesticides should be selected as appropriate for the specific pest being controlled and used in ways to avoid affecting non target organisms.
Whichever chemical controls you use, it is important to switch things up periodically to prevent the likelihood of pest resistance. Pest resistance occurs when an organism develops an immunity toward a treatment, making it necessary to use ever-stronger poisons against them. Insects and pathogens evolve much faster than we do, so there is a limit to what we can tolerate. Finally, after monitoring the situation and deciding which pests can be tolerated, using good cultural, mechanical, biological controls, and applying only necessary chemical controls, be sure to assess the situation, to make sure the problem is being corrected. If it isn’t, you need to go back and learn more about the pest(s) causing the problem to develop a new plan of action. Generally speaking, pests appear seasonally and on specific crops. Knowing when to look and where to look can give you a jump-start on controlling the pests that damage your garden plants. You can help the scientific community by participating in citizen science projects, such s the Big Bug Hunt, where you report insect sightings as you see them. This helps researchers develop better predictions about when pests are likely to appear in your area. Trichogramma wasps are small but mighty. ,_photo_was_taken_by_Dr_Victor_Fursov.jpg) Trichogramma wasp laying eggs in armyworm eggs (Dr Victor Fursov) CC BY-SA 4.0 These microscopic parasitic wasps protect an astounding collection of edible plants. It might be easier to list those they do not protect, but your almond, apple, avocado, beet, blackberry, blueberry, celery, cherry, corn, cotton, grape, orange and other citrus, legume, papaya, peach, peanut, pear, plum, pumpkin, quince, squash, strawberry, tomato, walnut, and zucchini plants and trees are better off when Trichogramma wasps are in the neighborhood. These tiny wasps protect your plants from damage by parasitizing the eggs of these garden pests:
Parasitic wasps
Parasitic wasps lay their eggs in many common garden pests. This group of beneficial wasps includes braconids, chalcids, Goniozus wasps, ichneumon wasps, and Trichogramma wasps. Female Trichogramma wasps seek out the eggs of pesky moths and butterflies and sawflies to use as nurseries for her own eggs. When she finds one, the first thing she does is drum on it with her antennae and ovipositor to see if it has already been used. Drumming also helps her determine how big and useful the host egg is. This dictates how many eggs she will insert. After being inserted into a host egg, the wasp egg develops, pupates, and then hatches, after which it feeds on the contents of the host egg. This turns the host black. If you use a hand lens and see a healthy white host egg with a chewed hole, it means the egg was not parasitized and a healthy (destructive) caterpillar emerged instead. Trichogramma wasp species Unless you are a scientist with a very powerful microscope, you will never see a Trichogramma wasp. At 1/25“ to 1/50” long, you could fit 20 to 40 of them nose-to-tail across a dime. If you could see them, you might be struck by the simple beauty of a minuscule yellow wasp with red eyes. Or, you might not. There are over 200 species of Trichogramma around the world. Before you order a shipment of Trichogramma wasps as a biocontrol, keep in mind that different species of Trichogramma parasitize different hosts. It is important that you order from a reputable seller to avoid releasing a threat to other beneficial insects into your garden. When reading product descriptions, take the time to do a little research before you buy. Trichogramma wasp eggs are shipped as larvae in host eggs that have been glued to cards. If you buy Trichogramma wasps for release, these tips will give them the best chance at being successful:
Keep in mind that Trichogramma wasps will not kill all the pests they come across. What they do is provide one piece of an integrated pest management program that uses natural processes to reduce the overall impact of pests, rather than spraying chemical poisons on your food. Watch out for the yellow jackets and hornets, leave mud daubers and paper wasps to go about their business, and add some insectary plants to attract and provide for beneficial wasps, such as the Trichogramma. Goniozus wasps can sting, but you’ll never have to worry about that.  Female Goniozus wasp (Jean-Jacques Kieffer) Public Domain Like many other parasitic wasps, adult Goniozus wasps mostly feed on nectar, sap, and other sweets. The benefit they provide is that they also parasitize pests of almond, apple, citrus, fig, pistachio, walnut, and coconut trees, as well as blueberries, blackberries, grapes, and strawberries.
Navel orangeworm, obliquebanded leafroller, and light brown apple moth caterpillars are favorite egg-laying hosts, giving Goniozus the common name of navel orangeworm wasp. Personally, I prefer Goniozus - in my mind, it’s the Gonzo wasp. These garden helpers also use banana scab moths and several insect pests associated with galls as hosts. Goniozus wasp description There are 20 different Goniozus wasp species, and they all look like tiny flying ants. Walking through the garden, you may simply see a very small, shiny brown or black wasp-waisted insect. Most insects who fit that description are beneficial, so resist the urge to swat them away. Instead, take a moment and see if you can tell what they are up to. Goniozus parasitism Similar to cuckoo bird species, which lay their eggs in the nests of other birds, Goniozus wasps are also known as cuckoo wasps because they lay their eggs in the bodies of other insects. Adult females use their stinging ovipositor (egg-laying tube) to paralyze their victims, injecting hosts repeatedly with venom. The venom of some Goniozus wasps is permanent, but not all. In those cases, the venom only lasts half an hour or so, so she has that much time to transport her victim, mostly by dragging the much larger host, to a good hiding spot. If necessary, she will continue to inject venom over several hours, if that’s how long it takes to get where she needs to go. Once tucked safely into a crevice somewhere, some females will feed on the juices of said caterpillar over the next few days, aiding in the development of her eggs. This does not always kill the host. In some cases, the host simply walks away, a little worse for the wear, until the eggs hatch and begin feeding from the inside out. Goniozus larvae go through several developmental stages over the next 2 or 3 days, attached to their host, ultimately spinning tiny cocoons around themselves before reaching adulthood. Apparently, Goniozus wasps have been observed paralyzing far more hosts than they can possibly use for egg-laying. No one knows why. How to attract Goniozus wasps Beneficial parasitic wasps can be attracted to your garden with insectary plants. Insectary plants provide the food and shelter needed by these garden helpers. Most insectary plants feature umbrella-shaped flowers commonly seen in carrot, dill, cumin, mint, and cilantro, or globe-shaped flowers, such as chives. Allowing these plants to go to seed not only attracts beneficial insects, but seeds then create perpetual, edible crops. Other insectary plants include cosmos, sweet alyssum, yarrow, dandelions, and borage. Adding these useful plants to your yard looks nice, too! Unlike beneficial parasitic wasps, hornets attack honey bees, steal honey, invade bat houses, girdle branches, and ruin summer picnics. So why would we want to tolerate hornets in the garden? What good can they do? Let’s find out!  European hornet (PiccoloNamek) CC BY 2.0 Hornet species Worldwide, there are 22 hornet (Vespa) species, including:
There are also 3 species of nocturnal Asian Provespa, which are not actually hornets. Despite their name, bald-faced hornets (Dolichovespula maculata) are not true hornets, either.  Bald-faced hornet (Beatriz Moisset) CC BY-SA 4.0 There is only one true hornet found in North America: the European hornet (Vespa crabro). Introduced in the 1800s, this hornet is now found throughout the U.S.  European hornet (Philip Cohen) CC BY 2.0 Hornet lifecycle Hornets are highly social insects. They live in large colonies, housed in papery hives, that are commonly built in dark crevices, such as dead tree trunks, under house eaves, and in your garage. Hives are made up of interconnected brood cells. Both the queen and workers can lay eggs. Fertilized eggs laid by the queen develop into sterile females, called ‘gynes’ while eggs produced by workers develop into males, called drones. Drones mate with the queen during ‘nuptial flights’. As a result, a hornet’s nest is largely populated by two nearly distinct gender-dictated populations. Workers care for the eggs as they move through larval and pupal stages, ultimately emerging as adult hornets.
Hornet description Hornets and yellow jackets are both types of wasps, though yellow jackets tend to be smaller, with more yellow and black, while hornets tend toward more black and white or yellow and brown coloration. Most hornets average 3/4” to 1”, while queens can be 1-1/2” long. If you look closely, you might be able to see that a male hornet abdomen has six segments, while females have seven segments and a stinging ovipositor.  European hornet face (USGS) Public Domain Hornet stings and allergies Like many other stinging insects, hornets become aggressive when they feel accosted (swung at, stepped on, sat on, that sort of thing), or when they believe their food supply or the colony are threatened. Hornet stings are more dangerous to humans that other insect stings because they contain higher concentrations of acetylcholine. Hornet stingers are not barbed and can be reused many times. Also, when one hornet stings you, it releases chemicals that tell other hornets to sting you, as well. These same chemicals are also released when you kill a hornet or spray a hornet’s nest with poison, so be forewarned. If you are allergic to stinging insects, you should always carry antihistamines or an EpiPen with you. Signs of an allergic reaction include shortness of breath, swelling of the face, lips, or throat, severe itching, weak or racing pulse, nausea, wheezing or gasping. If any of these symptoms occur, get medical help immediately. Call 911, grab a family member, or a neighbor right away. These symptoms can quickly escalate into a life-threatening situation. Otherwise, follow these steps to ease your temporary pain:
You can also take aspirin or acetaminophen to ease the pain, just be cautious about mixing medications, as that can cause yet another medical problem. Generally speaking, you are going to feel really miserable for 30 to 45 minutes, moderately uncomfortable for the rest of the afternoon, and you may experience discomfort for a week or so. You may also want to apply hydrocortisone or calamine lotion to the area. Pastes made of baking soda or colloidal oatmeal can also sooth the area. If you haven’t had a tetanus shot in the past 10 years, that can be a good idea, as well. So, why would we want hornets in the garden?
Hornet diet Adult hornets feed on sweets, such as fallen fruit, sap, and your lemonade. They also collect insects for their larvae. This is part of the reason why they cause us so much grief during picnic season. From a hornet’s point of view, it is simply defending a food source when it refuses to back down from your burger and fruit punch. In addition to your picnic, European hornets commonly chew up beetles, dragonflies, grasshoppers and crickets, katydids, locusts, mantises, moths, and other wasps. This pulp is then taken back to the colony, where it is fed to larvae in the nest.  Hornet eating honey bee (R. Bartz) CC BY-SA 2.5 If you start having a hornet problem while dining outside, you can reduce the chance of stings by placing a plate of meat and fruit somewhat away from the picnic table.
If hornets become a problem around your home, try excluding them before poisoning them. Those chemicals tend to create more problems than they resolve. There is far more to wasps and hornets than you might expect. This group of insects is massive and it contains many beneficial insects. You may not be familiar with chalcidoid wasps, but odds are pretty high they’ve been working hard in your garden all along.  Chalcid wasp ‘Leucospis gigas' (IronChris) CC BY-SA 2.5 The chalcidoid superfamily of wasps contains 22,500 known species, with an estimated 500,000 species yet to be named. One of those families in particular, the Chalcididae, gives us chalcid wasps. And figs. Chalcid wasp description Ranging from only 1.5 to 0.75 mm (1/50 - 1/100”), you could fit 12 to 24 chalcid wasps nose-to-tail across a dime, so you probably will never see one. If you could see them, you would understand how they got their name. The word ‘chalcid’ comes to us from the Greek word for ‘copper’ because most chalcid wasps are a metallic bronze or copper color, though some species are metallic blue or green, and some are the more classic black and yellow variety.  Chalcid wasp 'Omphale cornula’ (Hansson C, Shevtsova E) CC BY 3.0 Beneficial chalcid wasps
Most chalcids are parasitic wasps. They lay their eggs in several common garden pests. When the eggs hatch, larvae feed on the host insect before pupating into adult wasps. [I know, it’s sounds awful.] Those hosts include the eggs and larvae of flies, beetles, moths and butterflies, some spiders and nematodes, and true bugs. Since true bugs (Hemiptera) include aphids, leafhoppers, spittlebugs, thrips, whiteflies, and scale insects, I am all for more chalcid wasps! [Plus, I love figs!] Figs and tiny wasps While most chalcidoid wasps parasitize all those pests, a handful of them are phytophagous, which means the larvae hide and feed in stems, galls, seeds, and flowers. Fig flowers, in particular, are hidden clusters found inside a hollow structure called a syconium. Fig pollination is usually completed by tiny specialized wasps, such as chalcid wasps. But, not all chalcids are good. Chalcids as pests Other phytophagous chalcids are not so helpful. These tiny wasps are pests because they lay their eggs in seeds. When those eggs hatch, larvae eat the seeds of pistachios and alfalfa, among others, creating burrows and allowing fungal and bacterial diseases a point of entry. In many cases, sticky barriers can be used to reduce the damage caused by these pests. Most chalcids, however, are beneficial. You can attract chalcid wasps to your garden by installing insectary plants, such as yarrow. Wasps may have a bad reputation, but there are beneficial wasps, and ichneumon wasps [pronounced ick-NOO-mon] are one of those Good Guys. Well, mostly. Ichneumon wasps are parasitic wasps and they have been around for over 15 million years.  'Megarhyssa greenei' female (Bruce Marlin) CC BY-SA 2.5 There are somewhere between 60,000 and 100,000 different ichneumon wasp species in the world, with 5,000 species in North America. Clearly, with those numbers, there is significant variety in appearance.  Female 'Xanthopimpla punctata'. Ovipositor longer and more slender than stingers of other wasps (Vengoils) CC BY-SA 3.0 Ichneumon wasp description Like other wasps, the ichneumons have a narrow body and an even narrower waist. Some females have an especially long ovipositor, which is often mistaken for a stinger. Ranging in length from 1/10” to over 5” long, they can be black, brown, yellow, or some pattern combination of those colors. These wasps have 16 or more segments in their longer than average antennae. Ichneumons are solitary wasps. .jpg) Head of ichneumon wasp showing highly segmented antennae (Martin Cooper) CC BY 2.0 Common ichneumon prey Adult ichneumon wasps eat little or nothing. Their larvae, on the other hand, are voracious feeders of beetle, butterfly and moth, wasp, ant, fly, and sawfly larvae and pupae or chrysalises. This is what makes ichneumon wasps so helpful in the garden. They also parasitize beet armyworms, some spiders, and wood-boring grubs. _female.jpg) 'Echthrus reluctator', female (Charles J. Sharp) CC BY-SA 4.0 Some ichneumon wasps do this by using their long antennae to detect prey, then inserting the ovipositor into the wood, plant, or soil, to strike their prey, piercing its skin and inserting an egg. Other ichneumon wasps crawl down the stems of aquatic plants to inject eggs into water-dwelling insects. Yet another ichneumon is the parasite of a parasite, making it a hyperparasitoid. This ichneumon lays its eggs in moth-eating ant larvae. She emits chemicals that confuse the ants as she does her deed.  'Hercus fontinalis' larvae feeding on caterpillar (Beatriz Moisset) CC BY-SA 4.0 Ichneumon wasp lifecycle
Most parasitic wasps lay their eggs on, in, or near their prey, but ichneumon wasps kill their prey outright and then lay eggs. When the eggs hatch, larvae feed on the host’s body. After hatching and eating their host, ichneumon larvae spin cocoons and pupate in or near the exoskeletons of their first meal. When they emerge from their cocoon, they are adult wasps who go in search of a mate. These garden helpers do not sting and they are worth their weight in gold, so check before swatting at something just because it might be a wasp. [Swatting at wasps is usually a bad idea, anyway…} One of the best ways to attract and provide for beneficial ichneumon wasps is to plant coyote brush (Baccharis pilularis) and to maintain hedgerows. In 2015, dreaded chili thrips arrived in California from Texas and Florida. Originally from Southeast Asia or India, this pest first hit North America in 1991 and is expected to be a permanent part of our gardening experience from here on out.  Female chili thrips (Aderksen) CC BY-SA 3.0 Let’s see what we’re up against. Before we do that, however, let’s get one thing clear. Whether you are talking about many thrips, or just one (and there is never just one), they are both referred to as “thrips”, with the “s” on the end. I know, it’s strange, but there it is. It comes from an 18th century word meaning “woodworm”, which is even more strange since these pests are disease-carrying sap-suckers. So, what does a thrips look like? Chili thrips description Like other thrips, chili thrips (Scirtothrips dorsalis Hood) are really tiny - often less than 1/20” long. That works out to 8 or 9 thrips, standing nose-to-tail, across the head of a dime. Their pale bodies are thin and they have dark wings, but you may never get that close. What you may see is light-colored flecks of movement as you walk past a plant. That’s your first clue there is a problem. Plants vulnerable to chili thrips Your habaneros and Scotch bonnets are not the only plants susceptible to these pests. In fact, over 100 species [no, make that 200 species], from 40 different plant families [rather, 70 families], have been identified. Host plants include fruit trees, such as apples, bananas, cashews, citrus, figs, lychee, mango, pears, and even the beloved cocoa bean. Other garden favorites include asparagus, basil, beans, blueberries, buckwheat, corn, eggplant, grapes, peanuts, sweet peppers, soybeans, strawberries, and tomatoes, as well as many popular ornamentals, including chrysanthemums, coleus, camellia, Gerber daisies, poinsettias, pyracantha, roses, snapdragons, and zinnia.  Chili thrips damage to basil (USDA/National Pest Alert) Damage caused by chili thrips
Symptoms of chili thrips infestation are first seen as damage to the upper surfaces of leaves, creating yellowish-green or brown angular spots on the upper surface and a gray sheen on the under surface. Leaves may become thickened or start curling. As nutrients and water are pulled from the plant, stunting, bronzing, distorted or elongated leaves, and flower bud scarring are also seen. Severe infestation can lead to the complete defoliation of a plant and these pests can carry tomato spotted wilt virus, peanut necrosis virus, peanut chlorotic fan virus, and tobacco streak virus. Chili thrips lifecycle Female chili thrips insert eggs into leaves, petioles, fruits, leaf axils, in curled leaves, and in leaf litter. In other words, they can be anywhere. Those eggs hatch in about one week and go through two larval stages in the second week. A single adult female can lay 60 to 200 eggs in her lifetime. That works out to a lot of sap sucking, disease-carrying insects. Controlling chili thrips Fast moving, highly prolific, and devastating to many of our garden plants, chili thrips have already developed resistance to insecticides containing asbifenthrin, cyfluthrin, and permethrin, so don’t bother. As of 2016, chili thrips had not yet developed resistance to insecticides containing acephate, imidacloprid, and orspinosad, but that window of opportunity may already have passed, and who wants those chemicals on their food anyway? Spinosad is actually more effective and less damaging to the environment. Sticky barriers may be used to monitor for chili thrips, but they won’t control the problem. Your best defense against chili thrips is to encourage beneficial insects, such as green lacewings and minute pirate bugs. Certain predatory mites and thrips and parasitic wasps will also help in the battle against chili thrips. These garden helpers are all attracted to gardens with a wide variety of plants and flowers, a clean water supply, and the absence of broad spectrum pesticides. Sadly, releasing purchased predators into the garden rarely works out. If conditions are good, they will come to you. If conditions are not good, it doesn’t matter how many times you buy and release beneficial insects. They will simply leave or die. Dusty conditions should also be avoided. Give susceptible plants an occasional quick shower with the garden hose in the morning to make life more difficult for thrips of all sorts. Also, stressed plants are more susceptible to infestation than healthy plants. This is yet another reason for selecting resistant cultivars that are suited to your microclimate, putting them into quarantine until proven healthy, feeding and watering them when they need it, and then giving them a helping hand with row covers as they become hardened off to your garden. Since shearing cuts off the ends of all twigs, it should be avoided if thrips are suspected. It is simply too stressful for the plant. Reflective mulch may disrupt thrips flight, if you want to try that. Infested foliage should be removed, bagged, and taken to your local County Extension Office for identification. If you don’t have time for that trip, please throw the bag in the trash. Do not compost plant material infested with even one chili thrips.Compounding the problem, chili thrips damage looks a lot like chemical overspray, aphid feeding, and micronutrient deficiencies. Western grape rootworms are leaf beetles that eat the leaves of grapes, roses, and fireweed in spring and summer. If that weren’t bad enough, their offspring are found underground, chewing up the root system. The combined effect can be devastating. #/media/File:Bromius.obscurus.jpg) Western grape rootworm beetle (James Lindsey) CC BY-SA 3.0
These beetles are very small, averaging only 1/7” in length. This works out to 4 or 5 beetles standing end-to-end across a dime.
Unlike their more tan-colored cousins, western grape rootworms are usually black or reddish-brown with dull gray, yellow, or white hairs, and orangish-red antennae. Larvae are 1/4-inch long, C-shaped white grubs. These grubs have 3 pairs of prolegs, a reddish brown head, and black or brown mouthparts. Eggs are laid in clusters on old wood under loose bark. Male western grape rootworm beetles rub their legs together to attract females, the same way crickets and grasshoppers do each summer. Damage caused by western grape rootworms These beetles cut slit-like holes in leaves, shredding them to tatters. The leaves then dry up and die, reducing photosynthesis and food for the plant. Adult beetles may also be found feeding on berries, petioles, and the bark of new shoots. Underground, western grape rootworm larvae feed extensively on the root system and can cause considerable damage. Controlling western grape rootworms Since larvae spend most of their year 2-feet underground, control is generally only possible during spring, when larvae and adult beetles move to the surface. Monitor plants for signs of beetle feeding and handpick whenever possible. You can also use sticky barriers to capture beetles moving up and down the trunk. If you see a tiny beetle playing ‘possum, don’t be fooled. The western grape rootworm beetle uses that trick to avoid being eaten, often falling off a leaf, stiff-legged. With a name like Asian jumping worms, you might expect colorful, flamboyant gymnastics moving gleefully through the soil, helping your plants grow. Okay, that was a stretch. And it was mostly wrong.  Adult Asian jumping worm (WI DNR) I say mostly because, while not colorful, these worms really can move. Also known as snake worms, crazy worms, and Alabama jumpers, Asian jumping worms writhe violently when disturbed. They can even drop their tail when threatened. Sadly, instead of helping plants grow, these voracious feeders strip an area of nutrients, destroying the top soil layer, and leaving desolation in their wake. This interrupts thousands of years of evolution and nutrient cycling, threatens biodiversity, and increases erosion. The invasives mixed bag Before we get into the Asian jumping worm story, let me remind you that our beloved European nightcrawlers and honey bees are also non-native species. Sometimes invasives can be a good thing. This is not one of those times.  European nightcrawler As with many other situations involving invasive anything, the problem lies in imbalances. North American forests and farmlands have evolved, over thousands of years, to use surface plant litter as slow-release food and secure habitat for countless microorganisms, insects, reptiles, amphibians, and other life forms. Asian jumping worms eliminate that layer and they do it very quickly. What are jumping worms? Our more sedate earthworms tend to be reddish brown with a raised white or gray partial band part way down the body. That band is called the clitellum. Asian jumping worms, which can range from 3 to 7” long, are gray to dark brown, with a smooth the clitellum that goes all the way around and is closer to the head end. Also, while shiny, jumping worms do not produce the slime seen on many earthworms. Regardless of how you feel about that slime, it is very useful in creating soil aggregates that allow for the healthy movement of air, water, microorganisms, and roots through the soil. Jumping worms also tend to be more rigid than our squishy earthworms. There are three species of Asian jumping worm: Amynthas agrestis, A. tokioensis and Metaphire hilgendorfi, with A. agrestis being the most commonly seen. Native to Southeast Asia, jumping worms are believed to have been brought to North America in potted plants, bagged soil, or nursery stock, though we don’t know exactly when or how. Asian jumping worms have moved quickly westward, in worm terms, over the past 10 years and are now found in Oregon. As you can imagine, these continued movements are not just worms traveling on their own. Asian jumping worms end up in plants, mulch, and soil, on shoes and equipment, in agricultural produce, and in batches of fishing bait. They get transported by us, one gets loose, the problem spreads. It’s easy to do because these jumping worms spend their winters as tiny, pinhead size cocoons, filled with eggs, they reach adulthood twice as fast as our familiar earthworms and red wigglers, reproduce more rapidly, and are more aggressive. They can also thrive in higher densities and eat a wider variety of foods. The real problem with Asian jumping worms is where and how fast they feed. Damage caused by Asian jumping worms Asian jumping worms are too efficient. That may sound like a good thing, but too much of a good thing can be a bad thing. Let me explain. As earthworms feed on fungi and bacteria that grow on decomposing organic material, they burrow into the soil, excreting castings that are filled with broken down plant and animal material, churning the soil and improving soil structure, soil health, water retention, drainage, and nutrient cycling. Everybody’s happy. Plants and organisms grow. Life goes on.  Earthworm castings (Muhammad Mahdi Karim) CC BY-SA 2.5 Asian jumping worms are eating machines, quickly devouring all of the surface material in an area and leaving behind a trail of low-nutrient crumbles prone to serious erosion. Research has shown that jumping worm castes are different from those of other worms. Instead of the soft, brown, crumbly bits of plant food and soil amendment we associate with earthworm castings, Asian jumping worm castings look more like a pile of coffee grounds.
Asian jumping worms process nutrients so rapidly that their feeding releases nutrients faster than plants can absorb them, causing the nutrients to be washed, blown, or leached away. These castings contain important plant nutrients, such as potassium and calcium, and they tend to contain higher levels of heavy metals, such as iron and aluminum. When those crumbles are eroded away, those nutrients are lost. As a result, Asian jumping worm feeding quickly converts healthy, loamy soil in to granular, more sandy soil that tends to be hydrophobic, which means water runs off instead of sticking around long enough for plants to absorb. These invasive worms also push nutrients so deeply into the soil subsurface that many shallow-rooted plants cannot reach those important nutrients, leaving them to starve. What can you do about jumping worms? In a word, be diligent. Asian jumping worms generally cannot survive freezing winters, but anything less than that and they can become a serious problem in your yard. You can help prevent the spread of these invasive worms with these handy tips:
Bottom line, earthworms create topsoil while Asian jumping worms destroy it. Of course, that’s an oversimplification, but I want you to understand how important it is that these pests are kept in check. *Mustard Test
If you suspect the presences of Asian jumping worms in your garden, conduct a mustard test using these steps:
Worms, or wyrms as they were originally called, don’t technically exist. Wyrms referred a huge collection of tubular, limb-less critters back in the 1700’s. Of course, we all know what I mean when I say worm, right? Sure, we’ve all seen earthworms and red wigglers. But what about the 3-foot bristle worms, or the 22-foot African giant earthworm, or, are you ready for it? What about the 190-foot oceanic bootlace worm?!!? Crazy, right?  Earthworm and land planarian Worm description
Well, clearly, we don’t ave any 190-foot worms in our gardens. What we do have is long, squishy bodies that are easier to describe by what they don’t have. Worms do not have legs, true limbs, scales, lungs, a brain, a true digestive system, or a circulatory system. They breathe through their skin, which needs to be moist at all times. Dehydrated worms become paralyzed. You may be surprised to learn that many worms are not actually able to move themselves with muscles, the way we do. Instead, they move through the soil by the act of feeding. If you think about it, worms are one big food tube. Food is sucked into the mouth and passes through a pharynx, esophagus, crop, gizzard, and intestine, before being pushed out the other end. While worms do not have eyes, per se, some of them do have light sensing organs. Types of garden worms There are three different types of garden lifeforms that fall under the worm category:
Nematodes are round worms. Earthworms are segmented. And flatworms, such as land planarians are, well, flat. The flatworms and roundworms are known as helminths and tend to be parasites of one form or another. Worms improve soil Worms are an important part of decomposition, whether it is happening underground or in your compost piles. Worms improve soil structure and soil health, making life a lot easier for your plants. As worm populations increase, drainage and porosity, or permeability also improve. As worms eat, poop, and die, they create mucous-coated soil clumps, or aggregates, that have spaces for water, roots, and air to move through. These spaces, called macropores and micropores, are important factors in soil health. For example, in sandy soil, the spaces are very large and leaching can be a problem, while clay particles are very tiny and they hold tightly to water and nutrients, and often have compaction problems. Worms help offset those problems by helping to break down and decompose organic materials, improving soil structure, adding nutrients, and being part of the nitrogen cycle. Worms are an important part of the soil food web and they help keep plant and tree roots healthy. Food for worms Did you know that earthworms like coffee? It ends up that sprinkling coffee grounds around your yard is a good way to reduce compaction and a couple of fungal diseases. For some reason, worms tend to pull coffee ground deeper into the soil. We don’t know why. We do know that worms will eat dead plant material, insects, insect eggs, fungi, bacteria, dead animals, and even cardboard and paper. While we may all end up as food for worms, more often than not, it is the worms who become the entree. Worms are commonly eaten by birds, amphibians, reptiles, and many mammals. Skunks, moles, shrews, raccoons, and rats will all gobble a worm, given the opportunity, as will centipedes, beetles, and even other worms, such as land planarians. Worms that are not worms Caterpillars, such as the impressively large Achemon sphinx moth, carpenterworm, and tomato hornworm larvae are commonly referred to as worms, as are tiny pink codling moth larvae, apple maggots, armyworms, cutworms, inchworms, naval orangeworms, and destructive green cabbageworm larvae, as are the microscopic larvae of dryberry mites. The larval form of click beetles are also called wireworms. And some people call grubs worms, too, but I have no idea why Each of these not-worms is simply a developmental stage in a process of metamorphosis.. Help the worms in your yard Worms do not have much of an arsenal when it comes to defense. The best way to help the worms in your yard is to create a healthy environment that meets their needs. If you build it, they will come. These tips will help you create a worm-friendly habitat in your yard:
If you happen to use tower gardening or other containerized methods, you can always rescue a few worms stranded after a rain and add them to the pot. They and your plants will be better of! And if worms really fascinate you, you can also raise your own. This is called vermiculture. Your yard may look quiet on the surface, but there is a lot going on underground. Even when given time to rest, or go fallow, there are still billions of processes happening in the soil beneath your feet, and worms are an important part of those processes. Finally, there is a new threat in the world of soil organisms. This one is the Asian jumping worm. There will be more on that soon. What do peaches and potatoes have in common? The green peach aphid. Considered the world’s worst disease vector among garden plants, green peach aphids (Myzus persicae) love to feed on peach and potato leaves, along with dozens of other garden plants.  Winged adult green peach aphid (Public Domain) Green peach aphid description Green peach aphids are generally found in colonies of winged and wingless adults and immature nymphs. Green potato aphids look a lot like potato aphids (Macrosiphum euphorbiae). While potato aphids can be seen throughout the plant, green peach aphids prefer hiding on the underside of leaves. Adults may be bright or pale green, with a dark patch on the back (dorsum). Nymphs are pale green, yellowish, or pale pink. Eggs are elliptical in shape and only 1/50” long. At first, eggs are green or yellow, but they soon turn black, making them nearly impossible to see. Green peach aphids have a rather bizarre lifecycle that is too complex for this venue. You can read an excellent summary about it at the University of Florida website, if you are interested in that sort of thing. Damage caused by green peach aphids Green peach aphids often overwinter in the egg stage on stone fruits, particularly on peach and peach hybrids, though apricot and plum are also favored. In spring, these eggs hatch and nymphs begin feeding on buds, flowers, and new stems. A few generations later, which only takes a month or so, winged adults move to summer feeding areas. It would probably be simpler to list the garden plants that do not attract green peach aphids, but you do need to know where to look for these pests. Summer feeding can occur on artichoke, asparagus, beans, beets, broccoli, Brussels sprouts, cabbage, carrot, cauliflower, cantaloupe, celery, chili peppers, corn, cucumber, fennel, kale, kohlrabi, turnip, eggplant, lettuce, mustard,okra, parsley, parsnip, peas, peppers, potato, pumpkin, radish, spinach, squash, sunflowers, tomatoes, turnips, watercress, and watermelon. Aphids prefer feeding on tender new growth. This leads to wilting, water-stress, and stunting. It also generates a lot of honeydew (sugary insect poop), which provides the perfect growth medium for sooty mold. Heavy aphid feeding can weaken a plant to the point of death. The bigger problem, as with nearly all aphid species, is that these pests carry diseases. Green peach aphids may infect plants with a variety of viral diseases, including:
If potato leafroll virus appears in your garden, it is a good idea to remove the infected plant, plus three other plants in every direction, to prevent green peach aphids from spreading the disease even further. This is yet another reason why it is so important to plant certified disease-free plants in the first place. These pests are often found in greenhouses, so placing new plants in quarantine can go a long way toward preventing an infestation. They can also travel on the wind, so it's a constant battle.
Green peach aphid management The best way to control green peach aphids is to hit them in winter. This means removing overwintering sites, such as infested leaves, spent plant debris, and nearby weeds. Malva is a popular winter wonderland for aphids, so keep that weed away from your peach trees and potato plants. Bindweed, lambsquarters, penny cress, pigweed, sowthistle, tumbleweeds, white goosefoot, and rouge members of the nightshade family can also provide overwintering sites for this pest. As spring and summer come around, however, you can attract and protect beneficial predators, such as lady bugs, lacewings, parasitic wasps, and syrphid flies, by providing fresh water, planting a variety of insectary plants, and avoiding the use of broad spectrum pesticides. Most chemicals designed to kill aphids cause more harm than help by disrupting the lifecycle of many natural predators. There is also a parasitic fungus (Entomophthora aphidis) that attacks aphids, but you can’t do anything about that one. Early each June, in northern California, green peach aphids migrate into our gardens. You can prevent a full-blown infestation by monitoring plants on a weekly basis and using a damp rag or paper towel to wipe off colonies before they can really start propagating. A single female, hatched in spring, can reach sexual maturity in only 10 days, creating 20 generations in a single year. By the end of summer, this can result in billions of offspring. Two-spotted spider mites can kill off many of your garden plants as temperatures rise and humidity drops. Before a hot, dry summer kicks in, it’s a good idea to know what to look for. .jpg) Two female two-spotted spider mites with egg (Giles San Martin) CC BY-SA 2.0 Two-spotted spider mites (Tetranychus urticae) can become a serious threat to your citrus and other fruit trees, most vegetables, and many ornamentals, such as marigolds, roses, and salvia. Beans, blackberries, blueberries, cucumber, eggplant, lettuce, peas, squash, strawberries, and tomatoes are all favorite foods of the two-spotted spider mite.
Two-spotted spider mite description As arachnids, all mites have two body segments and eight legs. Two-spotted spider mite eggs are round to spherical, but very difficult to see. Instead, you may see the webbing used to protect those eggs. Colorless larvae, which start out with only six legs, go through two developmental stages to reach greenish-yellow, eight-legged adulthood. This transformation can occur in as little as 5 days, and females can lay 120 eggs in their lifetime, so populations can rapidly explode. An interesting note, unfertilized eggs hatch into males, while fertilized eggs hatch as females. This is called arrhenotoky. Males are smaller and have narrower bodies and are more active than females. These close cousins to red mites are greenish-yellow to brown, with two dark spots, and they even have a red winter phase, but you probably won’t be able to see them without a hand lens. [Those dark spots are accumulated body wastes, so they are not always visible.] At only 1/50” long, two-spotted spider mites are easier to find by looking at the damage they cause. Damage caused by two-spotted spider mites As sap-sucking pests, similar to citrus mealybugs and citrus bud mites, these mites pierce plant cells and remove the contents. Hidden from view by feeding on the underside of leaves, they often go unnoticed until the damage becomes obvious. Mite feeding causes stippling and bleaching. These damaged areas increase, causing bronzing and early leaf drop. If you look at the underside of these leaves, you will often see the cast-off exoskeletons of mites. You may also see extensive webbing over buds, stems and flowers. Extensive feeding can cause stunting and even plant death. How to manage two-spotted spider mites Since two-spotted spider mites feed on such a wide range of plants, they are difficult to control. Mites favor feeding on stressed plants, so proper feeding and irrigation can help your plants seem less appealing to these pests. In addition, you can use these tips to reduce problems caused by two-spotted spider mites:
Predatory mites, such as Phytoseiulus persimilis, ladybugs, minute pirate bugs, and lacewings are all beneficial insects that feed on two-spotted spider mites, so keep you yard hospitable to these helpful predators. Mites are developing resistance to most chemical pesticides, but insecticidal soaps are effective against mites, with horticultural oils (not dormant oils) coming in a close second. These treatments are only affective against the mites that come into contact with it, so repeat treatments are often necessary. |
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