Here's what I suggest. First, get something like a tarp, some plastic trash bags or a sheet, and put it under your trees, just like you do for a Christmas tree. Then, give your girls a good shake before you go hunting. The minute they feel a predator may be around they drop to the ground. They should be easily captured/collected on the tarp.
I haven't found that they do a whole lot of damage in my area, to cannabis, but still, if they're looking for something to eat and you've provided the smorgasbord, we can't be surprised if they sample.