Onions, chives, and garlic plants with pink roots are not happy.
This disease rarely causes significant problems in garlic, but it can shrink your onion and chive harvest by quite a bit.
The pink root pathogen
Pink root is caused by a fungi called Phoma terrestris. Phoma terrestris is nearly always present in the soil and it pretty much lasts forever. Normally, it causes no serious problems. If your onion plants are weakened by drought, insufficient or excessive fertilizer, water stress, insect feeding, compacted soil, or any number of other less than ideal circumstances, your onions may become susceptible. This pathogen thrives in temperatures between 75° and 85°F and can be moved around the garden by splashing rain or water, and on tools.
Symptoms of pink root
Aside from the obviously pink roots, plants infected with this fungal disease also exhibit roots that darken to red, purple, and, eventually, black. These roots shrivel up and die. These discolorations may move up into the bulb. This infection leads to stunting, but it rarely kills the plant. This disease looks a lot like fusarium wilt.
Preventing and controlling pink root
Keeping plants healthy and employing crop rotation are the two best ways to avoid pink root from causing too many problems. A note on crop rotation: do not follow a cereal crop with onions, as it creates conditions that promote this particular pathogen. Severe infestations can be eliminated with soil solarization, but that’s a pretty drastic measure for the home gardener.
If you see pink, purple, or black shriveled roots on your onions, try growing them in a different area, in fresh soil, and be sure to feed, weed, and water them properly, and protect them from insects, to ensure that they stay healthy enough to protect themselves.
If the lower limbs on your almond tree are turning brown, you have a problem.
While it is normal for the leaves on lower limbs to turn yellow because of being shaded by the limbs and leaves above, lower limb dieback (LLDB) goes much farther and can result in the death of your tree. LLDB first appeared in 2005. Scientists do not yet know what causes this condition, but learning how to avoid it can save your trees.
Symptoms of lower limb dieback
This disease normally appears in late April or May, on trees that are 7 or 8 years old. It starts out with the leaves on lower limbs yellowing, and then turning brown. Eventually, the entire branch becomes girdled by cankers and dies, right up to where it attaches to larger, scaffold branches, or the trunk. If you scrape the bark off of an affected limb, you will see brown spots in the wood. [Sorry, but I couldn't find an image I could use.]
Some almond varieties are more susceptible to lower limb dieback than others. Padre almonds are the most likely to get this disease, with Butte being a close second. Almond varieties that show some resistance to lower limb dieback include Aldrich, Carmel, Fritz, Mission, NePlus Ultra, Nonpareil, Sonora, and Wood Colony. If you are shopping for an almond bare root tree, you might consider one of these more resilient varieties.
Preventing lower limb dieback
While research is currently underway, it is believed that overly wet soil, low light levels, and root exposure to herbicides or excessive fertilizer may weaken trees, making them vulnerable to whatever it is that causes this problem. This is just the opposite of shade tree decline, in which severe drought slowly kills a mature tree, with the early symptoms being a lack of leaf cover in the upper canopy, or crown, of the tree.
Lower limb dieback occurs most often in years with a cool, wet spring, followed by high temperatures. Soil compaction and low infiltration rates are also believed to play a role in lower leaf dieback. Trees with hull rot also appear to be more likely to develop this condition. In this case, fumaric acid and other toxins are believed to accumulate in larger branches when multiple spurs are infected. In this weakened state, these trees are also more likely to be infected by fungal opportunists, such as Botryosphaeria dothidea and Phomopsis amygdali. Phomopsis amygdali causes the stoma to stay open, desiccating the tree. Botryosphaeria dothidea causes cankers on a wide variety of plants.
Keeping your trees healthy is the best way to prevent lower limb dieback. This means proper irrigation, reasonable applications of fertilizer (only after a soil test shows a need for it), and control of scale insects, which may play a role in the spread of this disease. Fixed copper, sulfur, and fungicide treatments have not been shown to be effective.
Geocarpy is a rare form of plant reproduction that practiced by peanuts and a few other plants you may, or may not, recognize.
While most plants wave their flowers at pollinators and then allow their fruit to swing freely, out in clear view, geocarpic plants are far more modest.
Geocarpic plants tend to live in areas that are harsh. Seasonal fires, extreme drought, and repeated freezing and thawing (solifluction) can make plant life difficult. Because of all this uncertainty, these plants have decided that it is better to push their flowers underground to develop into fruit. The floral stem, or peduncle, does all the pushing.
Types of geocarpy
The term geocarpy refers to any plant that ripens its fruit underground. There are three forms of geocarpy: hysterocarpy, amphicarpiy, and protogeocarpy. If the ovaries are fertilized above ground and then pushed underground, it is called hysterocarpy. Peanuts are hysterocarpic. If only some of the fruits are pushed underground, it is called amphicarpic. Protogeocarpic reproduction is really wild. These plants produce their flowers underground. Think about it. How are pollinators supposed to transfer pollen to the flower if it is underground?
Protogeocarpic plants have evolved a different type of flower. The stigmas, or pollen receptors, of protogeocarpic flowers push their way an inch or so above ground. Pollinators land on these threadlike, aerial stigmas, depositing pollen, which then travels down the stigma to the flower, underground. Here, the ovary is fertilized and fruit development occurs. I’m not sure why they have those names, but I like to think of plants waving their aboveground flowers ‘hysterically’ before heading underground, to remember which one is above ground.
In addition to peanuts (Arachis hypogaea), South African bitter cress (Cardamine hirsuta) and the Genuflecting plant (Spigelia genuflexa) also use this unique method of reproduction.
Do you have any geocarpic plants in your garden?
You may be surprised to learn that potting soil is not really soil at all.
Potting soil, also known as potting mix and potting compost, has been used by gardeners since the 1800’s, and there are many good reasons for doing so. First, let’s find out what, exactly, is in potting soil.
Potting soil ingredients
Potting soil is a manmade recipe often made out of composted bark, sand, perlite, peat, recycled mushroom compost, and mineral nutrients. These mixes are treated to create the best pH for plant growth. Some potting mixes contain slow-release fertilizers. You can find potting soil that is rated ‘organic’ according to OMRI regulations, and you can find potting mix that includes ground up old car tires. It’s one of those cases where you really do get what you pay for. If you are committed to organic gardening, be sure to look for the OMRI label.
Potting soil’s unique properties
Potting soil is designed to retain moisture and nutrients. [Because of this ability, fungus gnats are often attracted to pots filled with potting soil - it’s the moisture.] Potting soil is also sterilized to kill off pathogens and weed seeds. This is what makes it so useful in container gardening. Some potting soil mixes are designed for specific plant species, such as African violets or cactus. Fresh potting soil is also what keeps your window sill garden and holiday plants healthy and productive. Stale potting soil… not so much.
How to recondition potting soil
Old potting soil may not actually contain anything useful to your plants. Like garden soil, nutrients are ultimately depleted and must be replaced. Also, potting soil, in particular, becomes hydrophobic as it ages. This means that it actively repels water, allowing it to quickly drain out of the bottom of the contain, leaching valuable nutrients as it goes. You can either dump it out and buy new potting soil, or you can recondition what you have. To recondition old potting soil, simply top dress it with aged compost and water it in. No digging or repotting needed. Also, you can apply an attractive mulch of wood chips on top of your potting soil to act as a slow release of organic material and some nutrients.
Uses for potting soil
Because of its ability to retain water and nutrients while providing ideal soil structure, potting soil is the best choice for seed starting, transplanting, and up-potting. The loose potting soil is gentle to traumatized root hairs and eases the transition. Potting soil is also the best choice for vertical gardening, tower gardening, and raised beds.
If you love your trees (or your blueberries), be on the lookout for Asian longhorned beetles.
Native to China, Japan, and Korea, these invasive, wood boring beetles love to hitch overseas rides on wood-related packing materials: shavings, pallets, that sort of thing. In 1996, an infestation of Asian longhorned beetles (Anoplophora glabripennis) was discovered in Brooklyn. Two years later, a second sighting occurred in Chicago. Then, they were found in New York, New Jersey, and Illinois, where they are responsible for the removal of thousands of trees. These pests have already cost state and federal government (our tax dollars) over $168 million and that number looks to rise exponentially, now that they have expanded their range into California and Washington.
The potential economic impact was first estimated to be more than $41 billion. That number has increased to nearly $700 billion, and that’s before you factor in the damage to breakfast morale when the northeast’s sugar maples are attacked! Eradication efforts got into affect each time these invasive pests are found, sometimes successfully, sometimes not. The U.S. Customs Department is working hard to halt the importation of these pests. Eradication in the U.S. is still possible, but it’s an uphill battle. And they need our help.
Asian longhorned beetle identification
Asian longhorned beetles (ALBs), also known as starry sky or sky beetles, are easy to identify. Approximately one inch wide and and an inch-and-a-half long, they are shiny black with 20 white spots on each wing cover, and they feature an impressive set of black and white banded antennae. They have long, whitish-blue feet and large mandibles. Larvae are large and cream colored.
Adult female beetles chew pits into wood and then deposit their eggs into those pits, one at a time. She can lay up to 90 eggs in just a few weeks.
When the eggs hatch, larvae tunnel deep into the tree (where they are safe from predators and pesticides), leaving behind a trail of frass. Deep within the tree, the larvae go through several instars before entering a pupal stage.
As adults, they tunnel out of the tree, leaving 3/8-inch exit holes along trunks and branches. Piles of frass can be seen at the base of infected trees and in branch crotches. Branch dieback and leaf wilting are early signs of infestation. The egg sites and larval feeding make the trees susceptible to many other pests and diseases, as well as more vulnerable to damage from heavy winds. Sap is often seen oozing from wounds. This larval tunneling causes extensive damage and girdling, making the wood unusable and eventually killing the tree. Infested trees must be removed and destroyed by trained professionals. Do not attempt this yourself.
Trees susceptible to ALB
Many popular hardwood trees are vulnerable to ALB infestation. These trees include alder, ash, beech, birch, boxelder, elm, hackberry, hornbeam, horse chestnut, mimosa, planes, poplar, sycamore, and willow. And blueberries! And members of the Prunus family, which includes apricots, peaches, nectarines, cherries, and almonds! We do not yet know what the impact will be on California’s native hardwood trees.
Experts predict that this pest could cause more damage than gypsy moths, Dutch elm disease, and chestnut blight combined, destroyed millions of acres of trees across the country, in parks, along streets, in backyards, and in agriculture. Dead and dying trees are more likely to cause fires and they are unable to support the biodiversity that keeps a region healthy. If you consider all the wood-based products we use every day, ALB could cause many prices to increase significantly. All because of an insect.
If you see it, catch it! Report it!
If you see an Asian longhorned beetle, catch it. Period. Just do it. They don't bite or sting. While they can fly, they don’t do it very well and only for short distances. You can do this.
Your efforts could save millions of trees and billions of dollars. Seriously.
Put your captive in a glass jar [they chew through trees, remember?] and place it in the freezer. Be sure to label the jar with where you found it (GPS position, if possible), the date you found it, and your contact information. These reports are critical if we are to protect our trees. Using this information, experts can create quarantine zones and implement eradication programs most effectively.
If you live in California, call the CDFA hotline at 1-800-491-1899. In fact, put the number in your phone now, so you’ll have it if you ever need it. I did. If you live outside of California, report it to your state’s Department of Agriculture. Together, we can save millions of trees.
Pierce’s disease is becoming a major threat to grape vines and citrus trees.
The bacteria responsible for Pierce’s disease, Xylella fastidiosa, was first seen on grapes in Southern California in the late 1800’s, when it was called Anaheim vine disease. By the 1930’s and 1940’s, it had spread to California’s Central Valley. By the late 1990’s, the disease had spread to several California counties. This increase is believed to be, in part, a result of warmer temperatures allowing more of the bacteria to survive the winter. According to CABI, Pierce’s disease is now found throughout the Americas, and in Italy, Iran, and Taiwan.
Pierce’s disease is carried by sap-feeding insects. Most commonly, this means sharpshooters, such as blue-green and glassy-winged sharpshooters. [Did you know that sharpshooters can consume hundreds, or even thousands, of times their body weight in sap in their short lives?] Spittlebugs have also been found to carry this disease. Whichever insect is chewing on your grape vines, they inject the bacteria into the vine’s vascular bundle as they feed, making them a disease vector. These bacterium then live and reproduce in the xylem, clogging the flow of nutrients and water through the plant.
Pierce’s disease can occur on a large number of weedy and ornamental crops, such as wild grape, California blackberry, periwinkle, stinging nettle, eucalyptus, live oaks, blue elderberry, and mugwort. These plants are not affected by the bacteria that cause disease in grapes. But they do provide a transitionary location for the insects that carry the disease to your garden.
Symptoms of Pierce’s disease
Infected plants exhibit leaf scorching and stunting. These symptoms start out as slightly yellow or red leaf margins (edges) of white or red grape varieties, respectively. Concentric areas of infected leaves may dry up. You may also see ‘matchstick’ petioles, ‘green islands’ on mature brown stems, raisined clusters of fruit, and dieback. These symptoms do not normally appear until spring, after temperatures are above 65°F.
There is no cure for Pierce’s disease. In some cases, the disease will disappear on its own and we don’t yet know how or why. It seems to be a function of temperature, the timing of the initial infection, and the variety of plant being infected. Generally speaking, a late season infection, one that occurs after June 1st, has a 95% chance of recovery. Water stressed plants are more likely to succumb to the infection. If a plant becomes infected early in the season, the bacteria have time to become firmly established. Once that happens, you will ultimately have to remove the vine completely.
Pierce’s disease control and prevention
This disease triangle consists of the host plant, the feeding insect carrier, and the disease-causing bacteria. Break the connection between any one of those three and you can reduce the chances of disease. The easiest ways to prevent Pierce’s disease is to keep host weeds out of the area and treat for the sap-sucking insect pests. Since insect-eating birds, such as bluebirds, along with several predatory insects, love to eat sharpshooters, keep your garden welcoming to these natural helpers.
Monitor your plants for signs of Pierce’s disease so that you can act quickly, reducing the spread of the disease. Most of the vector insects are low fliers, so physical barriers can be used to quarantine potentially infected plants. During the dormant season, remove any vines that have been infected for more than one year. They will not recover and they will spread the disease to other plants as vector insects feed on them and then move to nearby plants for more feeding.
Ladies bugs, or lady beetles, are always welcome in the garden, except when they’re not. Because, if it’s a Mexican bean beetle, it’s the last thing you want to see in your garden!
Mexican bean beetles are found throughout Mexico and much of the eastern U.S., and in areas west of the Rockies that receive a lot of rain or irrigation. These pests have been found in and eradicated from California once. Let’s find out why Mexican bean beetles are so bad.
Mexican bean beetle identification
Mexican bean beetles look like ladybugs, sort of. They have the same oval, domed shaped, and they have spots. To be exact, Mexican bean beetles have eight black spots on each side. These evil cousins to ladybugs can range in color from golden yellow to a rusty brown. Larva look like spiny oval pills and the eggs are yellow. Pupae are found hanging from the underside of leaves.
Mexican bean beetle lifecycle
In late spring, adults emerge and begin feeding and breeding. Each female will lay hundreds of eggs in clusters on bean leaves. When these eggs hatch, the real damage begins. Heavy infestations can defoliate an entire field of legumes. After a few weeks of feeding, the larvae enter a pupal stage. Newly emerged adults often travel long distances in their search for food.
Mexican bean beetles (Epilachna varivestis) are a type of lady beetle that eats plants, rather than other insects. In particular, these pests feed on legumes. That means your cowpeas, mung beans, soybeans, green beans, wax beans, lima beans, peas, and fava beans are at risk. It also means you need to monitor any alfalfa, peanuts, wisteria, lupins, tamarind, carob, and lentils for signs of Mexican bean beetle feeding.
Mexican bean beetle damage and control
Adult beetles feed on the undersides of leaves, leaving them skeletonized. Beetles may also feed on fruit and flowers. The larvae eat even more than the adults! Luckily, parasitic wasps can do a lot to reduce bean beetle populations, so avoid using broad spectrum pesticides and insecticides. You can also use row covers when you know that Mexican bean beetles are present or likely to appear. As always, take the time to quarantine new plants.
If you live in California and suspect seeing a Mexican bean beetle, please try to capture it and report it to the California Pest Hotline at 1 (800) 491-1899, or contact your local Department of Agriculture.
Wax is made by honey bees to build the comb used to store honey and to protect larvae.
Did you know that plants also make wax?
Nearly all vascular plants manufacture wax. This wax is used as part of the cuticle, or outer layer of the epidermis, of leaves, stems, and even some fruits.
Having a waxy outer layer reduces evaporation, making it easier for plants to hang on to the water they need. It also reduces the chance of abrasion, when plant parts rub against each other. Finally, wax makes it more difficult for pests to attack.
Wax is actually a class of fatty compounds that are insoluble in water and tend to be relatively soft at room temperature. When honey bees are between 12 and 20 days old, they develop a special gland on their belly that converts the sugars in honey into waxy flakes. The flakes are collected by other bees and chewed up before being used to make new comb. [I thought you’d want to know about that.] Plants, however, have neither the organ nor the chewing ability. Instead, plants synthesize wax out of hydrocarbons, made up of fatty acids and long chain alcohols, along with aromatics, ketones, and other chemicals. The chemical make up of a plant’s wax varies by species and geographic location.
Plant wax candles
Carnauba wax, of shiny car and confectionary fame, is a wax made by the Brazilian palm Copernicia prunifera. A lighter colored substitute, ouricury wax, comes from the Brazilian feather palm Syagrus coronata. Several species of native bayberry (Myrica cerifera), also known as wax myrtle, and the succulent stems of candelilla (Euphorbia antisyphilitica), produce so much wax that they were used by Native Americans to make candles. In the case of bayberry, the berries are boiled until the wax separates from the plant material. After it hardens, it is removed from the soup. These candles are still made today, due to the pleasant smell as they burn. Candelilla plants are now endangered and collecting them is forbidden. Other plant waxes include castor wax, rice bran wax, and tallow tree wax.
The next time you look at a leaf or stem, take a closer look and see if wax is part of that plant’s defense system.
Moles are creatures of darkness. They almost never leave their tunnels. Often falsely blamed for plant damage, moles are primarily insect eaters.
Moles are rather funny looking. They have stubby, hairless tails, cylindrical bodies (usually 5 to 7 inches long), pointed snouts, and short, webbed hands and feet. They don’t see very well because their eyes are covered with skin, and you can’t see their ears. Mole fur, however, is quite thick and velvety, and moleskin is the stuff of hiking blister legends. There are 42 mole species worldwide, 7 of which live in North America, and 4 species found in California:
Moles like their privacy. Unless it’s the breeding season, you will only find one mole per tunnel system. Moles have one litter each year, usually with 3 or 4 young, in spring.
Differences between moles and pocket gophers
Many people assume that moles and voles (also known as pocket gophers) are related. They are not. Voles are plant eating rodents, while moles are primarily insect-eating members of the Scapanus species, more closely related to shrews. Crescent-shaped mounds with closed holes indicate the presence of pocket gophers. Pocket gopher populations can lead to girdled trees, slope erosion, and dead plants. Moles, on the other hand, have round mounds which may have open or closed holes, and long surface ridges from their shallow tunnels are often visible. Moles normally feed on worms, grubs, insects, and other invertebrates. Moles will occasionally eat mice, shrews, and nuts. Your average mole will eat 40 pounds of insects each year.
Moles create an extensive system of both deep and shallow tunnels. The deeper tunnels are their permanent housing, with separate rooms for food storage, sleeping, and rearing young. Tunnels are usually 2 inches in diameter and found 8 to 12 inches below the soil surface. The shallow tunnels are for hunting out grubs, worms, centipedes, and other soil dwelling creatures. It is the shallow tunnels that cause most of the problems associated with moles. As they burrow under the surface of the soil, looking for their supper, moles often dislodge smaller plants and expose root systems to the air, drying them out. If you want a lawn that looks like a putting green, moles are not your friends.
If you cannot tolerate moles in your garden or landscape, trapping will be necessary. While there are dozens of repellants, scaring devices, home remedies, and plants that claim to offend moles, research has not shown that any of these methods actually work. The only exception is castor oil solutions, which have been shown effective on eastern moles. Flooding tunnels wastes water and does not rid an area of moles. [They’ve dealt with floods for far longer than we have been gardening.]
Trapping always works. Underground harpoon traps and scissor-jaw traps are the most effective methods. Of course, this means dealing with a dead mole and a messy trap. Some new mole baits are showing limited effectiveness, but then you have to worry about children, pets, and local wildlife also suffering a horrible death. Plus, if your landscape was appealing to a mole before, it probably will be again, to a different mole. If you have valuable plants that need protection against moles, you can install a hardware cloth barrier 2-feet into the ground, with a 6-inch lip bent at a 90° angle away from the plant to thwart mole digging.
Moles are fascinating creatures. Some of the more interesting mole facts include:
If you can tolerate moles, they actually provide many benefits to the garden and landscape.
Did you know that mole saliva contains toxins that paralyze earthworms? Researchers have found underground storage spaces filled with thousands of paralyzed earthworms, for later eating.
Now you know.
Kuno scale is a pest of plum and other stone fruits.
Like other soft scale, kuno scale (Eulecanium kunoensis) is a sap-sucking insect that hides under a dome-shaped protective barrier. Unlike armored scales, which can be separated from their dome, kuno and other soft scales are attached to their dome.
Kuno scale description
Kuno scale females are 1/6 of an inch in diameter and a dark, shiny brown. They actually look like tiny beads on tree stems, during summer. Just before egg production, they turn yellow or orange, with black markings. During winter, they are more flattened and less shiny. If you remove a kuno scale from its host, you will see a visible lip on her body, which is used as a point of attachment. Nymphs are flattened, and either brown or yellow. Male cocoons are 1/12 of an inch long and translucent.
Kuno scale lifecycle
Eggs hatch under their mother in spring. These first instar nymphs are called ‘crawlers’ because they crawl away from her and find a place to feed on leaves throughout the summer, going through multiple instars as they feed. In fall, mature nymphs find a hiding place on twigs just before leaf fall. These nymphs overwinter on twigs and reach adulthood in spring, just in time to lay more eggs.
Kuno scale damage
As a sap-sucking insect, Kuno scale sucks phloem sap from twigs and leaves. While it prefers plum trees, Kuno scale can also be found on peach, cherry, nectarine, apricot, and almond, as well as rose, walnut, and pyracantha. These pests can populate an area so quickly, that it can seem as though they appeared overnight. Plants may appear water stressed. Heavy infestations can lead to twig dieback and premature leaf drop. Also, Kuno scale produces a lot of honeydew (sugary poop). Honeydew is the perfect growth medium for sooty mold. It also attracts ants, which will protect and farm Kuno scale. If you see ant trails on your plum tree, make a point of finding out where they are going in your tree.
Kuno scale control
Since ants protect Kuno scale from natural predators, blocking ants from getting up in your trees is the easiest control measure. To do this, simply wrap the tree trunk with a sticky barrier. You can also apply horticultural oil to twigs and the ends of branches just as buds are swelling, in spring. You can also try drenching the undersides of leaves in early summer, but this is tricky, because it’s not a good idea to spray dormant plum or walnut trees with oil, especially during periods of drought.
And, let’s face it, spraying the underside of leaves is a royal pain.
Stinging insects can really take the fun out gardening. Knowing what to watch for can reduce your chances of getting stung.
Some insects will bite you, while others have a chemical arsenal at their disposal that they can inject through a stinger which may or may not be barbed. While bug bites may suck, today we are talking about those insects with stingers. Those insects are bees, wasps, and one type of ant.
A stinger is a pointed organ, often attached to a venom gland. The venom causes pain and paralysis of specific organs within the victim. Normally found at the tail end of an insect, stingers are used as weapons against real and perceived threats. Most stingers are relatively smooth and can be used repeatedly. Honey bees and a handful of other species have barbed stingers that are torn from the insect’s body, causing it to die with minutes. These barbed stingers, once embedded in flesh, continue to saw their way deeper, injecting even more venom. This is why it is so important to remove the stinger as soon as possible after being stung. [Barbed stingers are able to sting other insects repeatedly without harming the attacker.]
Buzzing bees are usually a welcome sound in the garden. As highly efficient pollinators, they are the reason many of our crops produce food for us. There are over 20,000 species of bees around the world, but the honey bee is the most well known. If a honey bee stings you, it is because she feels that she, or her hive, are threatened. Moving deliberately and calmly around bees is often all it takes to avoid getting stung. There are four major types of bees found in North America: bumble bees, carpenter bees, honey bees, and sweat bees:
Bumble bees Bumble bees (or bumblebees) are important pollinators. Fat, furry, and hard working, it is best to leave these garden helpers alone. Their stings are about as painful as a honey bee sting, but they only sting when provoked. California varieties include the American bumble bee, western bumble bee, golden northern bumble bee, tricolored bumble bee, and the yellow-faced bumble bee. Small colonies often build nests under patios and attic soffits.
Carpenter bees Solitary carpenter bees build circular holes and tunnels in wood. While they may damage your fence, they are powerful pollinators. Male carpenter bees look like golden teddy bears and they cannot sting you. Female carpenter bees are a metallic black and rather noisy. Generally, they will not sting if you leave them alone.
Wasps are aggressive. They will come after you, and sting multiple times. While wasps do not pollinate flowers, they are garden predators. Wasps will also parasitize many garden pests by laying their eggs on or in other insects. Unlike most bees, which are covered with tiny hairs, wasps are smooth-bodied and are usually marked bands of black and yellow. Wasps have remained relatively unchanged over the past 34 million years. There are over 75,000 species of wasps around the world. Many different types of wasps found in California including blue-winged, braconids, common thread-waisted, black and yellow mud dauber, cuckoo, four-toothed mason, ichneumon, short-tailed ichneumon, and giant ichneumon, great black, great golden digger, horntail, leucospid, multillid, potter, spider wasps, and weevil wasps. Not all of these species attack humans. Hornets and yellow jackets are both types of wasps that do attack.
Hornets (Provespa and Vespa genera) There are 22 species of Vespa and 3 species of Provespa. Provespa are unique in that they are nocturnal. Hornets are aggressive social insects. They feed on sugary plants and fruit, as well as other insects, including honey bees. 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, so be forewarned. Hornets build ‘paper’ nests in trees and under the eaves of houses. Bald-faced hornets and European hornets are commonly found in California.
Yellow jackets Most yellow jackets are black and yellow, though some are black and white. Yellow jackets have a distinct side-to-side flying pattern and all female yellow jackets have barbed stingers that can reused several times. They do not carry pollen on their legs. Yellow jackets prey on pest insects., and they feed on nectar, fruit, and tree sap. Yellow jackets build paper nests in trees, burrows, and under house eaves. Only the inseminated queen lives through the winter. All the other members of a yellow jacket colony die the year they are born. Yellow jackets are responsible for the greatest number of allergic reactions among stinging insects. They are often found around trash cans and picnics.
There are many different ant species found in California, but only the red imported fire ant (RIFA) has a stinger. While other ants can inflict a painful bite, fire ant stings burn furiously for quite a while. There is no mistaking that sensation! Red imported fire ants (RIFA) came to North America in 1985, from South America. By 1998, they had spread throughout the southeastern states, from their point of entry in Alabama. By 2007, fire ants had found their way to the west coast and everywhere in between. Fire ants eat meat, grain, sugar, and grease. They are a highly organized social species that will work together to kill young livestock and wildlife. They can really dampen a picnic, too. Be on the look-out for mounds in the soil.
If you are allergic to wasps, you will also be allergic to hornets. 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.
If you get stung
If you are unlucky enough to get stung, inspect the area to see if a stinger is visible. If it is, scrape it out with your fingernail. Then, clean the area with soap and water, take an antihistamine, and apply an ice pack. 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, it can be a good idea, as well.
To avoid gettin stung, take the time to look before reaching into an area, and wear protective clothing when outside.
Hoophouses are growing in popularity as a way to protect plants from a variety of threats.
Traditionally used in commercial agriculture, hoophouses are similar to cold frames, greenhouses, and row covers in that they provide a physical barrier between frost, insect pests, and disease vectors and your crops.
Hoophouses are also known as poly tunnels. grow tunnels, high tunnels, and hoop greenhouses. Hoophouses are typically created from steel frames that are covered with plastic (polyethylene) sheeting. These frames can be square or semi-circular.
Hoophouses create heat
Hoophouses extend the growing season by several weeks by increasing temperatures. This can be done with mechanical heaters, or with passive solar heat. In areas with extreme cold, smaller hoophouses are placed under larger versions, creating a buffer zone. As the sun’s rays warm the plants and soil within a hoophouse, the plastic sheeting slows heat loss. The heat can come in, warming the plants and soil, but it cannot escape as fast, so temperatures continue to rise. This provides the warmth needed by many sun-loving plants, such as strawberries, raspberries, blackberries, eggplant, basil, and peppers, and As temperatures become too hot, fans and other forms of ventilation are added at either end, along with other helpful equipment.
Hoophouses offer control
Another benefit of hoophouses is that they allow growers to manipulate humidity, along with temperature and air flow. Crops prone to fungal diseases can receive extra air flow with the use fans. Hoophouses also provide protection against strong winds, hail, sunburn damage, and sudden, unexpected cold. In areas with too much heat, misters can be installed inside hoophouses to keep the environment conducive to strong growth. All this protection allows fruit and vegetables to develop at a steady pace. It also allows them to be grown during traditionally unproductive seasons, and it helps more sensitive plants overwinter without too much damage. Hoophouses also offer protection against many pests.
Pests blocked by hoophouses
Most flying insect pests (and neighborhood cats) are thwarted by the walls of a hoophouse. Not only are the plants harder to see or smell, the plastic wall creates an impenetrable barrier. This protection can extend to birds, rats, and squirrels, but only up to a point. Once these pests realize there is food inside, they will work harder to find a way in. The real protection is against insects that act as vectors for disease.
Hoophouses in the home garden
Smaller versions of commercial hoophouses are now available for purchase for the home garden, or you can create your own, using PVC or conduit.
If you had a hoophouse, what would you grow in it?
Bogs are a type of wetland.
There are three basic types of wetland: swamps, marches, and bogs.
Swamps feature trees and other woody plants, while marshes are home to grasses and other herbaceous plants. Both swamps and marshes are common to warmer regions. Bogs occur in area with low soil nutrients and lots of acidic surface water. Bogs generally occur in areas with cool temperatures and frequent rain. This combination of conditions slows both growth and decomposition.
Bogs are unique in that they are areas where dead plant material accumulates in layers called peat. This dead plant material is mostly made up of mosses, especially sphagnum moss. Peat can be several yards deep and it is traditionally used as a building material and as fuel for fires.
Plants in the heather family are the most commonly found in bogs. This family (Ericaceae) includes blueberries, cranberries, and huckleberries, along with azaleas. Carnivorous plants are also found in bogs. Evergreens and sedges are also common.
Types of bogs
Bogs are classified by either nutrient content, or according to local weather and geography. When classified according to nutrient content, a bog can either be eutrophic, mesotrophic, or oligotrophic. This ranking goes from most to least nutrients present. When bogs are classified according to local weather and geography, these names are used:
Bogs can be deadly, if something sinks below the surface. They can also be stunningly beautiful.
Netting can be used to protect your fruit and nut crops from marauding birds and squirrels. But, did you know that it can also be used to modify lightwaves from the sun? Read on
People have used nets to protect fruit and nut trees from birds for a very long time. Birds have a nasty habit of pecking a bite out of one fruit and then moving on to the next, and the next, leaving behind a wake of damaged fruit that is prone to rot and infestation. Netting is also used as hail protection, in areas prone to that particular weather pattern, and to reduce seed loss in newly planted areas. This is particularly helpful with pea, bean, and quinoa crops.
Pests thwarted by netting
Netting is most commonly used to protect fruit and nut crops from bird feeding. Netting can also be used to protect against squirrels, voles, rats, Junebugs, and dried fruit beetles, though that protection is fleeting. I have been able to harvest far more of my almond, apple, grape, blueberry, nectarine, and fig crops with addition of tree cages enclosed with netting. As soon as my young apricot and pear trees start producing fruit, they will get their very own tree cage, for the same reason.
The down-side of netting
As handy as netting can be, it does have a few problems associated with its use. First and foremost, it is made out of plastic and it is not nearly as durable as the advertisements make it out to be. In reality, birds will try repeatedly and with great enthusiasm to get at your fruit crop (or your chicken feed), tearing holes in the netting. Also, netting snags on every twig, nub, and button it comes across, damaging plants,, and adding more holes (and a certain measure of frustration). Birds and other wildlife have met with cruel and horrible deaths because of netting that has been allowed to blow on the wind or swish around in oceans, lakes, and other waterways. Finally, birds are not only things that can get caught in loose netting - we had a rat get tangled up in the netting over our chicken run. It was not a pleasant experience for anyone involved. So, if you opt to use netting, you will need to monitor it regularly for tears and trapped creatures, and please, for goodness sake, dispose of it properly. Now, what was I saying about lightwave manipulation?
Photo-selective netting is the latest in agricultural technology. As the plastic filaments used to make this particular type of netting are manufactured, light dispersive and reflective elements are built in. These elements screen out certain lightwaves and then scatter the light that is allowed through. This spectral manipulation allows farmers to decide which light-regulated physiological responses are promoted. The scattering effect increases the amount of light that reaches the inner canopy. By doing this, farmers can grow bigger fruit with less water. The netting provides wind protection and substantially reduces evaporation. This lowers the likelihood of water stress and water-related diseases.
How to use netting
If you simply drape netting over your garden beds or trees, birds and other fruit eaters will still be able to reach a large portion of your crop. To be effective, there must be a space between the netting and whatever is being protected. Ideally, the netting is held taut, bouncing birds off the surface, rather than entangling them. This can be achieved with a tree cage, PVC hoop, or other structure.
Netting is a simple way to protect many crops from feeding damage, but it has its limitations and needs to be handled responsibly. Whenever possible, hardware cloth is a safer, more durable option.
Buckwheat pancakes, buckwheat eye pillows, and soba noodles are all made from buckwheat seeds, but what is it, really? And what can it do for your garden or landscape?
Despite its name, buckwheat (Fagopyrum esculentum) is not a type of wheat. Nor is it a type of grass. Instead, buckwheat is related to knotweed, sorrel, and, you won’t believe this - rhubarb!
If you compare buckwheat seeds with rhubarb seeds, you can see the similarity. Both produce triangular seeds. Buckwheat gets its name because it is used like wheat, but it has triangular seeds, similar to the beech tree. [The Dutch word for beech is boec.] Buckwheat, like quinoa, is a type of pseudocereal.
Originally from Yemen, buckwheat was a popular food staple for nearly 8,000 years. This was true until nitrogen became commercially available, which made other cereal and pseudocereal crops more productive than buckwheat.
The buckwheat plant
Buckwheat has a taproot that goes deep in search of water, and a dense, fibrous root system that stays within the top 10 inches of soil. Here, roots produce a mild acid that breaks down phosphorus, making it easier to absorb. Buckwheat is three times more effective at phosphorus extraction than barley, and ten times more effective than wheat. In areas with excessive phosphorus, growing buckwheat can help bring micronutrients back into a better balance for other plants. When the buckwheat is used as a green manure, those nutrients are returned to the soil. The buckwheat plant reaches a height of 30 to 50 inches. Its seeds are a type of simple dry fruit called an achene.
How buckwheat grows
Buckwheat does not handle heat, drought, or compacted soil very well. That being said, it’s fast growth makes it the best choice for newly cleared or overly farmed land. I have planted buckwheat next to my fences, partially under large, established plants, in an effort to bring life to soil that was exposed to the elements for decades before we moved in.
How to grow buckwheat
You can broadcast buckwheat seeds over an area, or you can drill holes for it. Drilling 1/2 to 1-1/2 inch holes for your buckwheat seeds means more will grow, and local birds will get less. These holes can be surprisingly close together. Converting the farming instructions of 50 to 60 pounds of buckwheat seed per acre, using 15,000 seeds per pound, you can cram 15 to 20 buckwheat seeds per square foot of garden space.
Buckwheat pests and diseases
Like many other ancient grains and pseudograins, buckwheat has very few pests or diseases that affect it. Occasionally, leaf spot and root rot can take hold. Also, competition from lambsquarters and pigweed can seriously reduce buckwheat growth.
Buckwheat as cover crop and green manure
Buckwheat makes an excellent cover crop and green manure. Buckwheat is a fast-growing plant that grows well in crappy soil. Germination usually occurs in only 3 to 5 days. Because buckwheat grows so quickly, you can plant it just before harvesting one crop, and before the next crop takes hold. This will help stabilize the soil, support soil microorganisms, and add nutrients in just a few days. In less than 45 days, your buckwheat plants will grow, flower, and be ready for mowing, as a green manure. You can also mow your buckwheat in the early stages of flowering to encourage regrowth and to extend the growing season. If you want the seeds for food or replanting, they will be ready in 70 to 90 days.
Buckwheat as insectary
Buckwheat plants start producing flowers within 3 weeks, and those flowers can last for 10 weeks. This is good news because buckwheat flowers are favored pollen and nectar sources for many pollinators and beneficial insects that parasitize aphids, mites, and other garden pests. Some of these beneficials include minute pirate bugs, green lacewings, insidious flower bugs, hoverflies, predatory wasps, big-eyed bugs, tachinid flies. and lady beetles.
The “other” buckwheats
Completely different from the pseudograin buckwheat, California hosts a collection of over 125 native plants known as buckwheats. These plants are in the Eriogonum genus. You can find both annual and perennial native buckwheats. These plants are also enjoyed by butterflies and other beneficial insects. Unlike the edible buckwheat, native buckwheats are very drought tolerant, and most of them are evergreens, adding color and texture to the landscape for most of the year. Popular varieties of native buckwheat include:
Native buckwheat provides food and habitat to native beneficials, with minimal effort. Edible buckwheat suppresses weeds, attracts pollinators, and improves soil structure and soil health.
Whichever type of buckwheat you decide to add to the garden or foodscape, the soil and local beneficial insects are sure to improve!
Chickpea, gram, or garbanzo bean, these legumes have been cultivated for 7,500 years. High in protein and easy to grow, chickpeas also make an excellent green manure.
Speaking of green manure, chickpeas produce the most seeds when they are provided with plenty of sunlight and very little nitrogen. Being a legume, chickpeas are able to convert atmospheric nitrogen into a form usable as plant food. If they have access to too much nitrogen in the soil, you will get plenty of vegetative growth and very few seeds.
The chickpea plant
Chickpea plants (Cicer arietinum) grow 8 to 20 inches tall and are bushy. They have feathery leaves and delicate white flowers with pink, violet, or blue veins. Like other legumes, the seeds are called pulses. Often (incorrectly) called a pod, pulses are simple fruits that develop from a single carpel, and that usually open along a seam (dehisces). Each pulse contains one or two seeds. Chickpeas have taproots that can reach 15 to 40 inches down into the soil. This makes them a good choice for reducing compacted soil and improving soil structure. [Translation: this fall, pick the worst spot in your landscape and plant chickpeas. Fava beans are another good choice.]
There are four major chickpea varieties, and over 90 genotypes. The familiar garbanzo bean (kabuli chana) is light-colored, large, and smooth-coated. Cicer reticulatum only grows in Turkey. There are two black chickpeas: Desi chana and cici neri. Ceci neri are a rare large, black chickpea grown only in southeaster Italy. Desi chana is the closest relative to ancient chickpeas. It is small, dark, and rough-coated, and can be black, green, or speckled
How to grow chickpeas
Here in California, chickpeas are a winter crop that is usually started around the first frost date. To speed the process, you can start chickpea seeds indoors, in pots, several weeks ahead of time, as long as you can provide them with enough sunlight and protection from summer heat. Transplant seedlings into the garden when they are 4 to 5 inches tall. Chickpeas prefer full sun. They can be grown in partial shade, but you won’t get nearly the same production.
Chickpea seeds are planted deeply, from 1-1/2 to 2 inches deep. Contrary to popular myth, do not soak chickpea seeds before planting, or water heavily after planting, as this makes them susceptible to cracking. Seeds should be planted 3 to 6 inches apart and thinned to 6 inches between plants. If you are growing chickpeas in rows, space rows 18 to 24 inches apart. Your chickpeas will be ready to harvest in approximately 100 days. Chickpeas do not handle competition from weeds very well, so you need to stay on top of them. Also, high boron levels can stunt chickpea growth, so be sure to get your soil tested. There are also a few pests and diseases you’ll need to watch for.
Chickpea pests and diseases
Fusarium wilt, verticillium wilt, ascochyta blight, anthracnose, bacterial brown spot, bean mosaic, bacterial blight, cucumber mosaic, curly top, and several root rots affect chickpea plants, especially those caused by Pythium, Rhizoctonia, and Macrophomina. Charcoal root rot, white mold, and black rot may also occur, and nematodes can be a problem. Aphids, armyworms, corn earworms, cucumber beetles, cutworms, darkling beetles, leafhoppers, leafminers, loopers, lygus bugs, spider mites, stinkbugs, thrips, weevils, and wireworms may all try feeding on your chickpeas. Luckily, these plants can produce an abundant amount of food, and crop rotation goes a long way toward interrupting the lifecycle of most of these pests and diseases.
Did you know that roasted chickpeas can be ground up and used as a coffee substitute, or that chickpea water (aquafaba) can be used as an egg substitute to make merengue?
I didn’t either.
Good fences make good neighbors.
Fences in and around your garden can create spaces, cause problems, or they can be sturdy helpers. How do fences impact your garden?
Fences add perspective
While some gardeners (farmers) prefer wide-open, Nebraska-style landscapes, fencing can create manageable spaces. Short fences can line pathways, providing support to a row of tarragon, oregano, or sweet peppers, while a medium-sized fence can block a view of your pool pump and provide afternoon shade for more delicate plants, such as currants. Tall fences create a sense of security and privacy. They also provide structure for vining plants.
Fencing materials have an impact, too. A solid brick or stone fence has a very different feel than a crisp white picket fence, a rustic pole fence, or a cedar plank fence. The materials and the construction method used alter the look and feel of your property and your garden. They also impact the way your plants grow.
Fences as barriers
Neighborhood fences are a great way to keep kids and pets safely at home. A good fence can also block garden invaders, such as deer, gophers, squirrels, chipmunks, and rats. Of course, some of those pests will need more than a wattle fence (or a very tall fence, in the case of deer) to slow them down, but fences provide a good starting point. For burrowing pests, such as voles and rabbits, the fencing material needs to go underground a ways to be effective.
Fences and air flow
A solid fence can provide serious protection against strong winds. Rather than tearing through your garden, leaving broken stems and branches in its wake, the wind is pushed over and around your sanctuary, keeping everything safe. Sometimes that safety comes at a price: poor air flow. In gardens prone to fungal diseases, poor air flow is a liability. If you have a solid fence and fungal problems in your garden, judicious pruning for good air flow and proper plant spacing can counteract these problems.
Fences as climbing structures
Fences make it easy to grow vines and other climbing plants. They also provide a great support for espaliered fruit and nut trees. Fences can also be used in tandem with planting containers. A mounted rain gutter with end caps can transform a bare fence into a strawberry wall. Short walls or railings provide the support needed for container plants that a re prefect for growing herbs, lettuces, Swiss chards, spinach, and many other edibles, without taking up extra space. Fences are also a great place to hang garden tools!
Fences block sunlight
The same fences that offer protection from wind and marauding pests are the same structures that can block much-needed sunlight. Most garden plants need at least 6 to 8 hours of sunlight each day to thrive. If you have fences, it is important that you take the time to see how much sunlight nearby plants actually get. While a west-facing fence may offer respite from scorching summer afternoon sunlight, an east-facing fence will only provide that protection to your neighbor’s plants.
Some fencing materials, such as chain link or stone, require very little care. Other fences, particularly those made out of wood, have some special needs. Since wod can rot, these tips will help your wood fence last longer:
Make the most out of the fences in and around your garden or foodscape. And, if you have the time, do an online search for “unique garden fence ideas.” There are some gorgeous, creative, stunning ideas out there!
I started my journey growing peanuts when something emerged from a planting container that I hadn’t planted. And it was unmistakably a peanut.
The only thing I could figure was that one of my local scrub jays had ‘planted’ it for later consumption. At the time, I had no bandwidth for growing peanuts. So I dug it out to take a closer look at the root system. [Now I let them grow!]
Nuts that are not nuts
Peanuts, also known as goobers, or groundnuts, are legumes. This means that they are able to ‘fix’ atmospheric nitrogen into a form they can use as food, with a little help from certain bacteria that live on or in their roots. The botanic name, Arachis hypogaea, describes a legume that produces its seeds “under the earth”, in a behavior called geocarpy. Geocarpy is rare in the plant world. It is a means of reproduction in which pollinated flowers are transformed into specialized stems, called pegs. Pegs are budding ovaries that bend downward and push their way into the soil. Seeds are produced along these pegs. Unlike other plants, which produce seeds above ground for easy dispersal, the peanuts we eat are the underground seeds of the peanut plant. And they are not nuts at all.
Parts of a peanut
If you look closely, it is easy to see how peanuts are related to peas and beans. They have very similar seed structures. Each delicious peanut has five parts:
Peanut plants come in two forms: runners and bush. Bush varieties are 18 to 22 inches tall, while runners can spread out 28 to 31 inches. Peanuts are believed to be a human construct, through artificial selection between two wild varieties. This occurred in Argentina or Bolivia, nearly 8,000 years ago. Selective breeding of this first peanut has resulted in six major and two minor landraces. A landrace is a regional, domesticated variety. These groups are:
Until the 1930s, peanuts were used predominantly as a livestock feed. That was when the USDA actively promoted peanuts as a commercial crop for human consumption.
How to grow peanuts
While it’s true that peanuts prefer the sandy loam of the southeastern U.S., peanuts can be grown in raised beds and large containers that are filled with a lightweight potting soil. You can start peanuts in a tray filled with potting soil. Make one inch deep holes by hand or with a dibble, and drop one shelled peanut into each hole, cover with soil, and water well.
In commercial peanut fields, as peanut plants begin to yellow, machinery is used to dig plants out of the ground, give them a good shake, and then flip them over and leave them on the soil surface for a few days to dry. In the home garden, you will harvest your peanuts by simply pulling the plants out of the ground, giving them a good shake to get rid of any clinging soil, and leave them, upside-down, to dry for a few days. [You may want to do your peanut drying in the garage, to protect your harvest against marauding birds and squirrels.] Next, peanuts are threshed, or removed from their stems. You may be surprised to learn just how important the drying aspect of peanut harvesting is - peanuts stored with too much moisture can become infected with a fungus (Aspergillus flavus) that produces toxic substances that can be carcinogenic. Be sure to dry your peanuts thoroughly!
Cucamelons may look like tiny watermelons, but they taste more like sour cucumbers.
Also known as Mexican sour gherkin cucumbers, mouse melons, and pepquinos, cucamelons (Melothria scabra) are cucurbits, which make them cousin to squash, melons, and gourds.
The cucamelon plant
Cucamelons grow on vines that climb nearby supports using tendrils. These plants produce both male and female flowers, making them monoecious. This means the plants can pollinate themselves, but the individual flowers are not self-pollinating. Native to Central America and Mexico, cucamelons need warm to hot temperatures to get started. Once established, your cucamelon plants will continue to produce fruit well into November.
How to grow cucamelons
Seeds should be planted 1 inch deep and 6 to 10 inches apart. Cucamelons are more drought tolerant and more rugged than other cucumbers, but they are slow growers, at first. Since cucumbers perform best in rich soil with a pH of 5.5 to 6.5, your cucamelons will probably benefit from moderate acidification, and top dressing the planting area with aged compost is always a good idea.
The actual flavor is more akin to a tangy cucumber crossed with a fava bean. If you expect watermelon, you probably won’t like it. If, instead, you can bite into these grape-sized fruits with an open mind, you may end up with a new garden favorite!
Cottony cushion scale inspires a certain measure of fascination. One look at these intricate insects, and you’re sure to want to learn more.
Cottony cushion scale (Icerya purchasi) are soft scale insects. Like other scale insects, their lifecycle touches on the bizarre. But before we get started, take a look at this photo and see if you can figure out what, exactly, is insect and what might be something else.
Cottony cushion scale lifecycle
Females can produce young with or without the help of a male. She will lay 600 to 800 eggs. Before she does, she will carry them around in a white, fluted sac that can be 2 or 3 times the length of her body. Most people mistake this egg sac for the insect’s body. Did you?
The eggs hatch out into crawlers. First stage (instar) crawlers are red, with black legs and antennae. These newlings make their way to nearby leaf veins, where they will begin producing their telltale white, cottony secretion. As they grow, these tiny pests will shed their outgrown skins (molt) and grow a bigger protective coating. Second instar crawlers make their way to twigs and leaves. Third instars prefer branches. Adults are usually found on branches and tree trunks.
Nearly every cottony cushion scale insect you see will be female, and they tend to form colonies. The males have red wings, but are really too small to see. The image below was taken after a female and her eggs were collected and placed in a container until they hatched. The coin next to them is a dime.
Damage caused by cottony cushion scale
Scale insects feed by inserting tiny, straw-like structures into bark, leaves, or fruit. One attached, they will suck the sugary juices out of fruit, or mainline sap directly from the xylem. This high sugar diet results in the insects pooping out honeydew, an equally sweet, high nutrient discharge that ants and fungi just love. Heavy infestations can lead to overall stress and loss of vigor, branch dieback, and defoliation of affected areas. Very often, it is the presence of sooty mold and heavy ant traffic that will first cue you to the presence of scale insects.
How to control cottony cushion scale
Natural predators do a much better job of controlling these pests than we do. Specifically, the vedalia beetle (Rodolia cardinalis) and the parasitic fly (Cryptochaetum iceryae) feed only on this particular pest and nothing else. Normally, these two beneficial insects are all that is needed to control a cottony cushion scale infestation. Unfortunately, dust, ants, and insecticides can interrupt that assistance.
'Ants will actively protect and farm scale insects. You can remove that protection by attaching sticky barriers around the trunks of trees. Chemical controls are not generally effective against cottony cushion scale insects (regardless of what they say on the label).
Take a look at your trees on a regular basis to see if cottony cushion or other scale insects have set up shop in your garden.
You can grow a surprising amount of food in your own yard. Ask me how!
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