Found on the Pacific coast from southern California up to British Columbia.
Which tree species are at risk?
It feeds on willow, hawthorn, manzanita, oak, walnut, crabapple, pyracantha, California holly, coffee-berry, and other plants.
When is tussock moth active and what does it look like?
In southern California two generations may occur each year, but in other areas there is only one generation. In northern California, this insect lays eggs late in the summer in felt-like masses usually upon old cocoons. The masses are grayish-brown in color and usually between 1/4 and 3/8-inch in diameter. The eggs hatch early next spring. The larvae (caterpillars) are attractively colored with spots of red and yellow and have four rounded brush-like tufts on their backs.
What symptoms should I look for?
The young larvae skeletonize the leaves while the more mature larvae eat the entire leaf.
Treatment and management solutions?
We recommend an application of carbaryl or chlorpyrifos during the early stages of larval feeding for best results.
If you're concerned that your trees are infected by the western tussock, contact your local certified arborist for an inspection and treatment plan.