Traveling around parts of Sullivan County this week I noticed caterpillar tents again, but these tents are different than the ones you see in the spring. There is another caterpillar that is commonly confused with the eastern tent and gypsy moth caterpillars and that is the Fall Webworm. 

Fall Webworms also make tents in trees and eats leaves, but the fall webworm differ from the eastern tent and gypsy moth caterpillars in a couple ways. These caterpillars are about an inch to inch and a half long, typically pale yellow or green with black spots and long hairs. They build extensive webs at the ends of tree branches, enclosing leaves they feed on. Unlike tent caterpillars, their webs cover foliage rather than forming tents in branch crotches. Eggs are laid in masses on the undersides of leaves in summer. Larvae hatch, feed gregariously within their webs for four to six weeks, then drop to the ground to pupate in leaf litter or soil, overwintering until spring. Adults emerge as white moths with wingspans of about an inch and a half, sometimes with black spots. They target over 90 species of deciduous trees, including oaks, maples, and fruit trees. While unsightly, their feeding typically causes minimal long term damage to healthy trees since it occurs late in the growing season. Except for the aesthetic quality of the tents, which can be numerous, they won’t affect the entire tree. Just opening the webs will allow birds to get in and have a feast on the caterpillars. Or if you prefer all natural Bt spray is the strongest insecticide that can be used to eliminate them, followed by neem oil and then other chemical sprays like Sevin. 

  Beside the caterpillar issue, I noticed leaves starting to fall already. I have both oak and maple leaves coming down in my yard. The oak leaves are still perfectly green, so I think they have just come down from some of the afternoon thunderstorms, but the maple leaves have me concerned. 

The maple leaves are yellowish already which is not necessarily an issue, but they are filled with black spots, which is black spot fungus. Being that the trees are forty to fifty feet tall, I’m not going to spray the whole with fungicide. But this fall once all the leaves have fallen, all those leaves will need to be deposed of. I have the luxury of having a large firepit in my backyard so that I will be able to burn my leaves, but if that is not an option for you, check your town for leaf pickups. Do not put these leaves into your compost bin as they will spread the fungus to your compost. The leaves need to be removed and then the area around the tree can be sprayed with fungicide before the winter sets in and then again in the early spring. Fungus lies dormant in the soil over the winter and, if not treated, will continue to infect your plants the following year. Fungicides like sulfur, neem oil and Daconil will all be effective and should be rotated to prevent resistance. 

  And a couple things you can do to improve your plant’s health is to avoid soil compaction by limiting foot or vehicle traffic near roots. If you think the soil is compacted, aerate soil with a garden fork or add earthworms. We sell worms as live bait for fishing, but those same worms can help your plant’s roots. Apply mycorrhizal fungi (FoxFarm) or compost tea to boost root health and nutrient uptake, especially for stressed plants recovering from pest or disease damage.