United States Golf Association
Golf Course Superintendents Association of America
Professional Landcare Network
Iowa Golf Association
National Golf Foundation
Sports Turf Managers Association
American Society of Golf Course Architects
Irrigation Association
Iowa Turfgrass Industry

Turfgrass Information Center Password-Free Login - Michigan State Universtiy
National Turfgrass Evaluation Program
Weeds, Nebraska Extension Publications
Turfgrass/Integrated Weed Management
Management of Turfgrass Pests; Weeds, Diseases, and Insects
Fertilization Requirements
WeedAlert.com
PestWeb
TurfNet

Sod Producers
Toro
John Deere
Monsanto
Scotts
Rainbird
Jacobsen-Textron