You walk past a tree and notice leaves rolled up into neat tubes. What causes this and is it a problem?
There are several leafroller species found in California:
A quarantine is in place for the light brown apple moth. See if you live in an affected area by clicking on the CA Dept. of Food & Agriculture’s Boundary Index Map. If you live outside of California, you can contact your local Cooperative Extension Office for more information
Leafrollers start out as clusters of flat, irregularly shaped eggs often found on twigs and leaves. These egg masses are coated with a dark gray or brown glue that later bleaches to white, giving them an appearance similar to fish scales. If you look closely at an egg mass in spring, you can see tiny pinholes where larvae have hatched.
After hatching, larvae pull leaves into a cylinder for protection as they feed. Most larvae feed through summer and then overwinter as pupae, though some species continue feeding throughout the year, causing considerable damage.
When disturbed, leafroller caterpillars tend to wriggle wildly and then rappel to the ground on a single silken thread.
You can grow a surprising amount of food in your own yard. Ask me how!