The cherries are ripening, so I went out and hung old CDs on the trees to scare away the birds. Birds will do a number on ripe cherries. I don't mind them getting a few up at the top where I can't reach, but I sure don't want to find beak marks in every other cherry on the tree.
CDs work great. I use old CDs---damaged ones or ones from defunct computer programs. I throw them in a drawer during the year, and in the spring I get them out, tie a loop of yarn through the center, and hang them on the trees. They turn and flash and scare the birds away. More cherries for me!