The bird seed that falls out of the feeder when the crash land to eat is sprouting in my garden. I have no clue what type of bird food it is since it was here from the previous homeowner. It has some sunflower seeds and little brown circle seeds, also fruit and nuts that I dont think are sprouting. I am pulling them from the veggie garden, but I let them grow in a 3 ft x 2 ft area directly under the feeder. Should I keep the sprouts? should I thin them? How do I know which ones to pull. Any advise I would be greatful for.