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Chemical: Contact GCDNR for specific recommendations. SRotted knagweed: A short-lived perennial or biennial forb that reproduces by seed only. Seed prolifically,up to 40,000 seeds/plant! Again a sporadic resident of Grand County but has been found on CR 1 nearby. Management methods include: • Cultural: Prevention by maintaining vigorous stands of desirable vegetation and minimizing soil disturbance. Using certified weed free hay. • Mechanical: hand pulling or digging out root and bagging plant that has gone to flower/seed can reduce population. • Biological: Root and Seed head weevils (Cynhocleonus achates and Larinus mWutus J attack the roots and reduce seed production in Spotted and Diffuse knapweeds. This is an option for large infestations,though optimum results take 3-5 years. To obtain the insects, contact the Colorado Department of Agriculture's Insectary in Palisade, Colorado at 970-464-7916. Yellow toadflax: Perennial forb spreading primarily by extensive root system making control extremely difficult once established. Escaped ornamental sometimes referred to as Butter and Eggs. Yellow toadflax is known to be present in small amounts on the Yust ranch. Management methods include: • Cultural: Prevention by minimizing soil disturbance,maintaining healthy stands, using certified weed free hay, checking seed packets to be sure this plant is not included. • Mechanical: Hand pulling or digging is not recommended for eradication of Yellow toadflax because it's unlikely that the entire root will be excavated and a new plant is likely to occur.A single new plant might be an exception. Tillage is not recommended due to the creeping root system. • Biological: Calonhasia lunula, a predatory noctuid moth,feeds on leaves and flowers of Yellow toadflax. Eteobalea intermediella, a root boring moth and Mecinus janthinus a stem boring weevil are also available. For more information, contact the Colorado Department of Agriculture's Insectary in Palisade, Colorado at 970-464-7916. Downy Brome/ChealMss: An annual or winter annual grass found in any disturbed area or roadside. Very invasive and can outcompete native vegetation and creates high fire danger in rangelands and roadsides. It is present in many areas of the County;though DNR does not have a good idea of how much is present, we have been discussing options to begin a management program for this species. Integrating efforts with BLM and USFS will be critical. Management methods include: Cultural: Prevention by minimizing soil disturbance and early detection/eradication.