First generation scarlet oak sawfly larvae are beginning to skeletonize oak leaves in southwest Ohio. The larvae are currently in the 1st and 2nd instar stages and a little less than 1/8" long. Despite this sawfly's common name, larvae may be found feeding on a wide range of oaks including pin, black, red, and white oaks as well as its namesake oak.

Is it a birds-nest or is it something else? Birds-nest fungi are fascinating organisms, complete with little nest-like spore casings that act as splash cups, and peridioles complete with funicular cords. Oh, what wonders.

This is the time of the year when rust diseases make it easy to spot wild hawthorns growing along Ohio trails as well as in landscapes. They have orange spotted leaves and "orange-hairy haws." I may be exaggerating a bit, but these rust symptoms can certainly make woodland hikes interesting.

Northern Masked Chafers and Japanese Beetles are on the wing in southern Ohio. These scarabs (family Scarabaeidae) are two of the three most common "white grub producing" beetles found beneath turfgrass in Ohio. The third potential participant in the grub-party are Southern Masked Chafers which have not yet appeared on the scene.

 

The Ohio Department of Agriculture (ODA) recently announced plans to begin aerial treatments designed to disrupt gypsy moth mating later this summer. Treatments will be applied to 32,526 acres in fifteen counties across the state. 
 

The gypsy moth is a non-native, invasive species that feeds on the leaves of more than 300 different trees and shrubs and is especially fond of oak as a caterpillar as shown below.

 

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A couple of weeks ago, me and several of my Extension colleagues came across so-called marginal leaf fold galls on an oak on the OSU campus during a photography workshop. Since that time, I'm commonly finding these galls on oaks belonging to the "red oak group" as well as a similar gall on black locust in southwest Ohio.

First generation nests of the deceptively named Fall Webworms are now becoming evident in Ohio. One of the most common question that I get about these moth caterpillars is, "why are they called "fall webworms" when it's not fall?"

I'm an unabashed fan of willows. Of course, no tree is perfect and willows have a few pests. Thankfully, the depth of their vital spark means willows are capable of handling the depredations of most pests. However, the pests I'm highlighting can make trees look bad.

Canada Thistle in southwest Ohio is starting to show the "ghostly" white symptoms of bacterial infections. The tops of infected plants look like they were dipped in bleach. The bacterium produces a chemical called tagetitoxin which is a RNA polymerase III inhibitor that blocks the production of chloroplasts.

Making a correct tree identification is the critical first step in correctly diagnosing a tree problem. Of course, sometimes the diagnosis identifies the tree. Insect galls are often so host-specific, they can give you six-legs up on tree identification.