We have a deck with attached gazebo on the back of the house. It's under a maple tree that's been there, probably 70 years, and we left it because the shade is wonderful.
Every spring, those little helicopter seeds come floating down and as usual, every year the cracks between the deck boards get filled with the seeds. Then, in the years they are left there too long, we have little maple trees growing from the cracks of our deck.
This year I have, for every night for a week or 2, been using the tool TheHusbandHalf made for me to get rid of the seeds/trees.
He took an old 2 1/2 - 3 inch scraper and duct taped (most of the world's problems can be solved with duct tape or WD-40) it to an old broom handle, and I just shove it between the boards. Sometimes the seeds fall through, some don't. The one's that don't, I sweep up and spread all over the grass. When they sprout, MyJohnDeere will cut them down.
It's a lot of work, but the shade is so nice!