While collecting the bark and ambrosia beetle traps that were set up in the arboretum I noticed lots of insect activity everywhere. It had just rained all night and morning, but it was warm and the sun was now peaking out. I’ve found that this is a great time to look for all sorts of critters. Amphibians start walking around, box turtles, snakes and especially the insects. They sit on leaves in patches of sun that makes it to the undergrowth. I took note of two logs in particular because they were both recently dead beech logs and I checked them out for ambrosia beetle activity. Ambrosia beetles are small, wood boring beetles that make little galleries inside trees where they raise a brood in chambers. Each chamber has a larvae that feeds on the fungal symbiont that the mother introduced into the wood. The mother often times even guards the entry hole into the log!
With the bark removed we can see this is an ambrosia beetle because it continues its bore hole right into the wood. A bark beetle would bore a hole through the bark and then make the squiggly lines you see in a barkless log.It takes some digging o find the brood chambers! My professor was able to get this beautiful chip out with some nice brood chambers coming off the main tunnel. There are even 2 pupae still in it!
The first log had few signs of ambrosia beetles but it did have many other insects all over it and under its bark. Several ichneumon wasps were probing the wood with their huge ovipositors. Under the loose bark I found lots of Silvanidae beetles which feed in fungi. I also found some darkling beetles and a nice sized pseudoscorpion!
The second log, which was really a whole mature beech tree that had snapped about 10 feet up and then was held up by neighboring trees was ambrosia beetle heaven. All kinds of beetle heaven really. More Silvanidae, rove beetles, lots of buprestidae exit holes and even larvae after I pulled back some bark. Ichneumon wasps also took quite an interest in this log too and I even saw two wasps with pseudoscorpions clamped to their legs! I’ve read about this but never seen it! A good way to move from log to log I guess. Anyway this log was filled with ambrosia beetle holes so I came back after my lab work was done and chiseled out some ambrosia beetles. I was able to extract many adults from several species that I have yet to identify. Also when I came back to this log I found the king of click beetles. The Eastern Eyed Click Beetle! Its HUGE (for a click beetle.) It must be one of the largest beetles around. About as wide as your finger and about 2 inches long and the coloration is just brilliant. A piece of art that grows in wood, feeding on Cerambycidae larvae.
Now here’s something new to me. Poison ivy being infected by a rust fungus! It’s called Pileolaria brevipes. There is hardly any information on it more than I could tell just by looking at it so I went ahead and collected it.
The fungus has deformed and enlarged the stem and it is releasing tons of brown spores. Back at the lab I put it under the microscope and snapped a picture of the spores. Even poison ivy gets lesions. Pretty neat!