This is an E-supplement to GAO-09-509 This document presents the results of GAO's survey of land managers from the Department of Agriculture's Forest Service and the Department of the Interior's Bureau of Land Management (BLM) and National Park Service field units regarding their perspectives on off-highway vehicle (OHV) use on federal lands. In order to learn about these managers' perspectives on OHV use in their units, we conducted a Web-based survey of all national forests and BLM field offices, as well as Park Service units most likely to have OHV use. We obtained a 100 percent response rate from the recipients of our survey. In this e-supplement we present the survey results, by agency, regarding land managers' perspectives on trends in OHV use on federal lands from fiscal year 2004 to fiscal year 2008, the impacts of such use, management and enforcement actions taken by the agencies, and challenges they face in addressing OHV use. We do not report results for question 24; we determined that the responses to this question were unreliable because some respondents had interpreted the question more broadly than intended. A more detailed discussion of our scope and methodology is contained in our report "Federal Lands: Enhanced Planning Could Assist Agencies in Managing Increased Use of Off-Highway Vehicles," GAO-09-509(Washington, D.C.: June 2009). We administered the survey from November 2008 to February 2009 in accordance with generally accepted government auditing standards.