Sycamore Tree Damage

Home Grown  by Keith Reed
From a landscape pest perspective, 2016 has turned out to be the year of the caterpillar. We’ve had problems with webworms since June and armyworms on turfgrass (and a few ornamentals) are also showing up in significant numbers throughout our area. We’ve also had a report or two of pumpkins being wiped out with melonworms.

It looks like we are having at least one more big caterpillar outbreak this growing season. Look closely at your sycamore trees and there is a good chance you are going to see many leaves almost completely eaten. This is likely being caused by the Sycamore tussoc moth caterpillar.

Just like the other pests mentioned, these are not going to cause irreparable harm to a well-established sycamore tree, so treating for them is generally not suggested. However, because of a couple of unique characteristics, they need to be discussed.

As a quick reminder, these pests are all unrelated, but they share similar characteristics and life cycle. They hatch from eggs as larvae (the caterpillar). After the caterpillar feeding frenzy, they pupate and eventually become moths, and off they go to begin the life cycle again.

Sycamore tussocs are very fuzzy white caterpillars with brown heads. They have brown tufts of longer hair on the front and the same (in white) on their rear. This gives them an intriguing look (cute would not be too much of a stretch) that just begs for to be picked up for a closer inspection.

Be advised, that while they do not bite, they can release a toxin when touched that can cause significant dermatitis in some people. It’s best to simply leave them alone. The weather will soon cool, causing them to disappear.

On another topic, Stillwater residents mark your calendar for this fall’s Household Hazardous Waste Event. It will be held Saturday October 15th from 8am to 1pm. This is the perfect opportunity for you to dispose of old/unused lawn and garden products such as pesticides and fertilizers. Some products have a longer shelf life than others so it’s hard to say with certainty what might still be good and what is not, so here is a quick an easy guide.

If you can’t read the label, if it’s been stored in sunlight, if the container is brittle or rotten, if a granular product has gotten wet or rock hard, or if you can’t remember the last time it was used, it’s probably safe to assume you should get rid of the product. The City of Stillwater’s program is an easy and environmentally responsible way to do that.

For more information on this or any other horticultural topic, you can contact Keith Reed, the Horticulturist in the Payne County Extension office. Keith can be reached via email at, phone at 405-747-8320, or in person at the Payne County Extension office, located at 315 W. 6th in Stillwater.

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