Recently added to the Early Detection/Rapid Response List for the State of Idaho, this plant was most recently found near the Nevada border in Twin Falls County. This plant often invades pastures, rangelands, agriculture, and many other sites. This asteracea family plant is covered with fine hairs and the leaves are divided into narrow segments with the leaf tip being narrow and undivided. Leaves have a distinct light colored mid-rib. The bracts have long, sharp, stiff spines about an inch long. This starthistle spine starts out flat at the base. It grows to a height of 4-6 feet, has a purple to red flower color, of which produces a small seed with a plume to allow it to disperse through the wind.
This is one of the most aggressive invaders to be introduced. Once established it discourages grazing, thus other species are over-grazed which gives an advantage to more invasion of the weed. Although forageable in the early spring, it has an extremely bitter taste. Spines are so stiff that livestock and wildlife will not travel through the areas, not to mention the inability of the recreationist to utilize the site.
Panorama and video taken 9/2014