I'm in North Carolina and have 5 sweet gum trees in my
yard. Some are close to my house. I'm selectively cutting off branches, and I'm using the wood to grow shiitake
mushrooms! Also, I have a low spot in my yard that has been collecting
water. I'm planning on digging out the topsoil in the low spot (and use it for
gardening elsewhere on my property), and I'll rake my plethora of sweet gum balls to fill the hole. I'll let you know how the "sweet gum ball hugelkultur" works out.