Planting and Selecting Tree Species for Stormwater Detention Basins

Summary

Dry detention basins are a type of stormwater management system that temporarily fill with water during rainstorms then drain over the course of several hours. In Central New Jersey, nursery grown trees are occasionally planted in these basins for aesthetic reasons, or to fulfill mitigation requirements. When these systems are not regularly mowed, volunteer tree species can become established in detention basins.  The species, size, and condition of both volunteer and nursery trees were recorded during a broader study on the condition of detention basins in the Central New Jersey (US) region. Condition was ranked on a scale of 1 to 4 based on the quality of the tree canopy and trunk, a rank of 1 indicated very poor condition. The nursery trees usually ranked lower than the volunteer trees and were comprised of a different collection of species. Observations of the size and number of trees in detention basins were also used to model the effects of trees on the performance of the study’s detention basins. Detention basins provide a novel opportunity for increasing or restoring a community’s tree canopy, but it is crucial to select appropriate species and planting methods to ensure success.