Sycamore - 100 Most Common North American Trees

"Sycamore is best suited for soils which are moist and do not dry out. Dry soil can lead to short life for this wet-site-tolerant tree. Sycamore has been cursed by horticulturists and others because it is said to be messy, dropping leaves and small twigs throughout the year, particularly in dry weather. However, the tree grows in places which appear most unsuitable to plant growth, such as in small cut out planting pits in sidewalks and in other areas with low soil oxygen and high pH.
Unfortunately, aggressive roots often raise and destroy nearby sidewalks. The dense shade created by the tree’s canopy may interfere with the growth of lawn grasses beneath it. In addition, the leaves which fall to the ground in autumn reportedly release a substance which can kill newly planted grass. Best not planted in yards due to messy habit, it should be saved for the toughest sites and supplied with some irrigation in drought. Allow at least 12 feet (preferrably more) of soil between the sidewalk and curb when planting as a street tree." - From Fact Sheet on Sycamore - USDA Forest Service

How to Manage Sycamore
Sycamore Habit and Culture