I don't like not having many large trees on my property (6 acres), but right now I'm thankful, and what ARE large, are maples (small leaves) and elm (smaller leaves).
The closest large tree is a maple, and if it fell over, it would probably have the top in my pond, so I'm saying this just to give you an idea how close. I see leaves in the pond each evening, and in the skimmer, but so far not many are on the bottom. I suspect when the trees are done shedding their leaves, I'll use my net and scoop out as many as I can. I've planted trees closer to the pond, but all are more ornamental types, grow slowly and small leaves, so shouldn't be much of a problem with leaves even when the get larger. Red Buds, Dogwood, Japanese Maple. There is also an oak tree that is about 10' tall, but they grow really slow, too. It's at it's point in life where one of these years it's going to really shoot up, though! That is about the same distance as the large maple, but different end of the pond. I cut down a HUGE partly rotten maple that would have been about 6' from the back side of the pond. That's what caused me root problems during my dig, but nothing an ax could not handle!
The trees in IL are lovely this week, and getting prettier as the days of fall continue. We are having 80's for highs and 50's for lows, can't get any more perfect for weather in my opinion. Sunny days, too, and expected through next weekend now they are saying. Love it!!! Going to do some kayaking and horseback riding this weekend.
Enjoy!