Hackberrys grow very quickly, you can water them and watch it grow like a weed. They also fall down in storms. I removed one from my yard and will be planting an Eastern Persimmon instead.
OK, here's a pretty thorough guide to the hackberry: https://homeguides.sfgate.com/special-care-hackberry-tree-56...
Sounds like you should keep crap off the trunk so it doesn't rot, it needs to be pruned to grow right, and if the soil gets dry it will start dropping leaves about it.