Any whitewood lying on the ground outside for a year is probably going to be firewood, no matter where it is.
Reasons-
Fungus loves whitewood - nomnomnom. Esp with dry rot, you can never really tell just by looking at it. Even just a little bit of fungal activity will make a piece of wood blow up if you try to make a bow from it- the wood must be at full strength
Insects, beetles, larvae, etc like to munch on it
Now I know halfeye has made bows from dead standing hophornbeam, but if you're just starting out, then I suggest cutting something fresh rather than putting a lot of work into something that was doomed from the start.