General pasture weed management resources:

• UW Extension Weed Science website
• UW Weed ID on-line identification tool
• Dirty Dozen & Beyond: 25 Pasture Weeds of Wisconsin (University of Wisconsin)

Toxic plants’ databases and information:

• University of Wisconsin Poisonous Plants of Concern to Wisconsin’s Livestock
• Canadian Poisonous Plants Information System
• Colorado Guide to Poisonous Plants
• Cornell Plants Poisonous to Livestock database
• Texas A&M Toxic Plants of Texas database
• University of Illinois School of Vet Medicine Poisonous Plants database
• University of Minnesota Horse Program: Pasture Weed Management page
• USDA Poisonous Plant Research Laboratory (Logan, Utah) and ARS Bulletin 415 Plants Poisonous to Livestock in the Western USA