This is a reference book on the classification, distribution, ecology and control of poisonous and aggressively invasive plant species on rangeland. The plants covered include leafy spurge, snakeweeds, thistles and knapweeds, woody species such as juniper, rabbitbrush, oakbrush, mesquite and saltcedar, and other noxious weeds such as dyers woad, cheatgrass and tansy ragwort.