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have vegetative buds that give rise to new shoots. Patch expansion can be dramatic. In Colorado, Dalmatian toadflax shoot density increased over 1,200 percent in six years at one location and 190 percent over three years at another. Yellow toadflax seedlings produce vegetative shoots from root buds two to three weeks after germination. Mature toadflax have well-developed and extensive root systems. Dalmatian toadflax roots may penetrate the soil 4 feet [o ]0 feet Dalmatian toadflax maybe controlled and lateral roots may extend 10 feet from the pazent plant; while yellow toadflax with Tordon 22K at 2 pvA sprayed at roots grow 3 feet deep or more with lateral roots that may extend several yards. flowering or in fall. Flowering Dalmatian toadflax typically flowers begining in late May or June in Colorado and may continue until fall, particularly if moisture is not limiting. Yellow toadflax begins to flower when shoots aze from ] 6 to 24 inches tall, mid- to late May along the Front Range in Colorado, although at higher elevations (9,000 feet or more), flowering may not begin until late July. Yellow toadflax may not flower until fall under drought conditions. Yellow toadflax shoot phenology in any given patch may range from vegetative to flowering [o seed set, depending on [he time of season and environmental conditions (particulazly moisture). This contributes to management difficulties. MANAGEMENT All toadflax species aze very difficult to control and management plans should integrate as many strategies as possible to increase potential for success. Assess the condition and composition of the existing plant community in an infested area then determine the approximate composition of the desired plant Yellow toadflax appears to be more community needed to achieve land management goals and objectives. Create a difficult to manage than Dalmatian management plan that combines vazious control strategies to foster development toadflax. In Colorado, control from of the desired plant community. Tordon applied at flowering has been most consistent and typicauy, 4 pvA is Chemical and Cultural Management of Dalmatian Toadflax recommended. Dalmatian toadflax may be controlled with Tordon 22K at 2 pt/A sprayed at flowering or in fall. In Colorado, rates of 2, 4, and 8 pVA of Tordon were compared and control longevity was greatest from the 2 pt rate, apparently because competition from crested wheatgrass was maintained. Researchers in Wyoming treated Dalmatian toadflax in early September, 1994, with Tordon at 2 p[/A, [hen seeded the following year in April or August with `Hycresi' crested wheatgrass, `Luna' pubescent wheatgrass, `Critana' thickspike wheatgrass, `Bozoisky' Russian wildrye, or `Sodaz' s[reambank wheatgrass. The combination of spraying and seeding competitive grasses controlled Dalmatian toadflax better than spraying alone. Three years after treatments were started, control of Dalmatian toadflax ranged from 61 percent to 86 percent where grasses were seeded in April and from 76 percent to 95 percent from the August seeding, compared to no control from spraying alone. Chemical Control of Yellow Toadflax Yellow toadflax appears to be more difficult to manage than Dalmatian toadflax. In Colorado, control from Tordon applied at flowering has been most consistent and typically, 4 pt/A is recommended. Yellow roadflax usually recovers from a single application. For example, Tordon applied a[ 4 or 8 pt/A controlled 13 percent and 69 percent of yellow toadflax three years after treatments were applied. Other reseazch conducted in Colorado suggests that yellow toadflax control may be improved if Tordon is applied over three consecutive years, but control varied with location. In one experiment conducted at high altitude (Camp Hale; elevation approximately 10,000 feet), 4 ptlA of