Our condo complex in Silver Spring looks like it has a terrible infestation...

Asked August 29, 2013, 7:45 PM EDT

Our condo complex in Silver Spring looks like it has a terrible infestation of sider mites all over trees and shrubs and it's spreading!!! The management is terrible and owners are concerned we will lose all of our beautiful shrubs and trees. What can we do? The trees and shrubs look as if they are covered in spider webs and the leaves are dying and have holes eaten in them. I read an article on the internet that said the county extension center may help but I can't find Montgomery County's EC. Help!!

Montgomery County Maryland insect identification fall webworm

1 Response

Although spider mites are active in many plants, your description suggests that you are seeing the webs of the Fall Webworm. This insect is enjoying a banner year and is active in many species of trees and shrubs. This insect is a moth in the adult stage and a caterpillar in the larval stage. It is the caterpillar that feeds on the leaves and creates the extensive webbing. Fortunately, this insect is a late season feeder and the damage done is not always lethal. There may be some branch dieback, but it is not likely to kill the entire plant. Some homeowners choose to prune out the branches when the webbing is fully in place and the insects are actively feeding inside the web. Other homeowners will simply disrupt the webbing with a stick and allow birds to access the caterpillars. There is also a safe insecticide that will control the caterpillars: Bacillus thurengiensis 'Kurstaki', commonly referred to as 'Bt', kills only caterpillars and does not hurt other insects, animals, plants, or people. It is too late to take any action now. The caterpillars are generally finished and are going into pupation. The adult moths will emerge in the weeks to come and lay more eggs on select host plants.
There is no county program to assist in the control of this insect. Normally, the insect is not as populace as it is this year. Nature usually takes care of itself, so hopefully, weather conditions and native predators will take care of the situation next year.
You will also notice that there are lots of spiders active this year. That, too, is simply an indicator that there is a huge population of many insect species this year and the spiders, being excellent predators, have ample food.