Try taking a tennis ball cut a small hole in it. Then take some string (the stronger the better) make a large knot and stuff it into the slit in the ball. Now you can throw the ball up into the tree. Try snagging a branch close by or part of the plane. I've used this method many time and it worked for me. But, I must admit that each succeding flight that (*&%$ magnetic tree grew stronger. That was one of the reasons I joined my local RC club!