Sir Speedy

Memnoch, have you identified the unknown tree yet? It looks like a Black Cherry, Prunus Serrotina, from what I can see of it. I have them all over the yard as the squirrells go nuts over the fruit. Im a couple hours east of you in NC. The bark is dark reddish brown with small white dots all over the place? Also if you cut it the wood has a smell very similar to black cherry.
I'm starting my second year of Bonsai and used a couple of the ones I found last year. Eastern tent caterpillar (Malacosoma americanum) LOVE the leaves and will make a mess of the tree if given half a chance. They emerge at the start of spring. The tree will be completely defoliated with a disgusting looking web of worms, it wont kill the tree but it looks ugly and they make a mess. Dont just chop it or it will send a large number of shoots, and create the bulge Teebeard was talking about with your Juny. Cut just above the lowest branch and train that as the new apex, rinse and repeat as needed. The bark scars easily and will form huge caluses and ugly spots, which can be of use if you plan it properly. You can defoliate them a couple times to help ramify later on (one of the experiments from last year). I didnt have much luck keeping the leaves small so make sure you nip off the buds after it puts out two or so leaves, or chop the leaf in half and a new branch will spout from its base. They thicken up pretty quickly and the wood gets pretty hard when it hardens off so make sure you take your time and be carefull when wiring. Dont use copper wire, it reacts with the chemicals of the tree. The fruit, if you are able to keep the squirrels off, can be used for preserves or to flavor drinks like brandy, vodka, or "mountain dew".
I have a couple larger ones I am going to attempt to reduce this year.