 |
||||||||||||
|
Tent Cats are going Walk-About
|
||||||||||||
|
Taken from the B.Y.G.L. (Buckeye Yard and Garden Online) Newsletter
Contributing Authors: Pam Bennett, Joe Boggs, Cindy Meyer, Jim Chatfield, Erik Draper, Dave Dyke, Gary Gao, David Goerig, Tim Malinich, Becky McCann, Bridget Meiring, Amy Stone and Curtis Young |
||||||||||||
 |
||||||||||||
|
Participants at this week's Southwest Ohio BYGLive! Diagnostic Walk-About noted that EASTERN TENT CATERPILLARS (Malacosoma americanum) are now reaching the final stage of their development. The late instar caterpillars are abandoning their highly visible silk nests located in branch forks to crawl off trees and go on their own walk-about in search of pupation sites.
The caterpillars are covered in short, grayish-white hairs, and they have a distinct, unbroken white stripe down their backs. The caterpillars prefer to feed on trees in the family Rosaceae, particularly those in the genus Prunus, such as cherries. However, once the caterpillars commence their walk-abouts, they may appear on a wide variety of plants. Fortunately, they do little or no feeding so damage is inconsequential. |
||||||||||||
 |
||||||||||||
|
Oak Apples
|
||||||||||||
| Dave Shetlar reported that OAK-APPLE GALLS are now becoming apparent on their namesake host. These unusual plant growths range in size at maturity from 1-2" in diameter and are named for their resemblance to apples. The galls are constructed of leaf tissue that has been hijacked by a gall wasp (Family Cynipidae) to surround a single wasp larva located within a seed-like structure positioned at the center of the gall. There are over 50 species of gall wasps that are known to produce oak-apple galls in North America and there are probably at least 10-15 distinct species of oak-apple gall wasps found in Ohio. The exact species of gall-wasp that is responsible for producing the oak-apple gall can be identified based on the gall's structure, size, color, and oak host. Cutting the gall open will reveal the gall's internal structure. In general, there are two groups of oak-apple galls; specifically, those with internal tissue composed of a mass of white fibers radiating from the central larval capsule, and those with tissue that strongly resembles the flesh of an apple; it is spongy and juicy. Beyond the internal structure, oak-apple galls are further identified based on the color of the gall, whether or not the surface of the gall is smooth, dimpled, or covered in bumps, and whether or not the gall has spots. The so-called SPONGY OAK-APPLE GALL is produced by the gall wasp, Amphibolips confluenta, on scarlet, red, and black oaks. The galls may be up to 2" in diameter and as their common name implies, the internal tissue is spongy and closely resembles the flesh of an apple. The surface of the gall is light green, smooth, and free of spots. The LARGE EMPTY OAK-APPLE GALL is produced by the wasp, A. quercusinanis (syn. A. inanis). The gall is also found on scarlet and red oaks and measures up to 2" in diameter. However, the internal structure of this gall is composed of white fibers radiating from the central larval structure. The surface of the gall is light-green and covered with purplish-red bumps. As with all plant galls, oak-apple galls change their appearance once they reach "maturity"; this is the point where a mature gall-making wasp emerges from the gall. For example, both of the aforementioned galls turn tannish-brown and the fibers in the large empty oak-apple gall become sparse; thus, the common name. Also, as with most leaf galls, oak-apple galls cause little harm to the overall health of their oak hosts. |
||||||||||||
 |
||||||||||||
 |
||||||||||||