We received a very valid question today from an architecture firm regarding weights of trees and plants for a green roof application. The simplest and (safest) way to calculate this is using the following chart:
These are estimates only based on a field test of average soil weight, with average moisture.
The rootball dimensions were given to us by our very experienced friend at Eagle Mountain Tree Farm.
I hope this quick chart answers some questions regarding tree sizes for planters, streetscapes, green roof/live roof plantings, and equipment questions! Also, keep these dimensions in mind when planting in shallow areas, or spaces with a lot of underground utilities!