Advisory Concerning Tree Trimming Operations at the Bureau of Forestry

The Office of Inspector General (OIG) has identified an opportunity to immediately improve the effectiveness and efficiency of the Department of Streets and Sanitation’s (DSS) Bureau of Forestry. The issue was identified during an OIG investigation involving the Bureau of Forestry, which is responsible for trimming trees and responding to tree emergencies throughout the City.

Before the advent of 311 in 1999, DSS used a grid-based approach, which involved dispatching crews to trim all the trees in grid-sized sections of the City. This systematic approach allowed DSS to trim City trees on a five-year, rotating schedule. DSS currently trims City trees using a reactive, 311 request-based approach. Accordingly, the City relies on residents’ calls to 311 to identify trees in need of trimming, rather than using a systematically proactive, arboriculturally based approach. When residents want a tree in their area trimmed, they call 311, their request is logged, and, if the request does not involve an emergency, DSS handles the request in the order it was received. Since DSS crews must travel throughout the City to handle individual 311 requests, they spend more time traveling and fewer City trees are trimmed. In addition, since some area residents do not regularly call 311 to request tree trims, many City trees have not been trimmed in over 10 years.

According to the Monitor Group’s report, issued on May 1, 2009, a grid-based approach would make the Bureau of Forestry much more efficientreducing the average crew’s travel time by 35% and the average cost per tree trim by 60%. The decrease in travel and equipment setup and teardown time for DSS employees would also result in more of the City receiving much-needed tree trimming services, because DSS could increase its daily tree trims per crew by 147%. This would result in 87% more addresses receiving services over the course of a year.

Given the tremendous benefits of an arboriculturally appropriate, grid-based approach to tree-trimming, OIG urges DSS to review the 2009 Monitor Group report—which further describes the benefits of adopting this approach and includes detailed implementation recommendations—and take the necessary steps in order to optimize its use of City resources, more effectively maintain and preserve the urban forest as a critical City asset, and better and more equitably serve City residents.