Nebraska Noxious Weed List
Canada thistle is a non-native perennial forb, which originated in Eurasia and North Africa. This very aggressive weed spreads by rhizomes and seeds. The extensive root system produces as much growth under-ground as there is growth above ground, making this noxious weed a tough one to control.
Diffuse knapweed is a non-native biennial or short lived perennial noxious weed that originated in Eurasia. It rapidly invades pasture, rangeland, roadsides and meadows. It can cause a serious decline in forage and crop production, and is not preferred by livestock as forage.
Giant or Japanese knotweed is an upright shrub-like perennial that can grow up to 10 feet tall. It is native to Asia. This knotweed is very invasive, and can form large dense colonies. The alternate leaves on the stems are up to 6 inches long and 3-4 inches wide, triangular or heart shaped.
Leafy spurge in a non-native perennial forb, brought here for Eurasia. This plant spreads two ways. First by seeds, which explode up to 15 feet away from the plant when the plant is mature. The seeds are also spread by wildlife and birds. Leafy spurge also spreads by an aggressive underground root system. Researchers have dug roots as long as 28 feet, with rhizomes shooting up along these roots, in an effort to start new plants.
Musk thistle is a non-native noxious weed that originated in Eurasia. It often grows in pastures, rangeland, open woodlands, roadsides, and disturbed areas.
Also known as common reed, this perennial grass has a native species in Nebraska, as well as a non-native species which was introduced from Europe. Phragmites grows along banks of ponds, lakes, streams, marshes, roadsides, ditches and in wet fields. In the past several years, many of these species have hybridized, and have spread rapidly crowding out native plants, altering wildlife habitat, and altering water flow in streams and on river systems in Nebraska.
Plumeless thistle is a biennial forb, which originated in Eurasia. This noxious thistle grows 3-4 feet tall, with purple flowers that bloom from June to August in Nebraska. Spiny-winged leaves, just beneath the head of a plumeless thistle plant, is a characteristic separating it from the similar musk thistle. Another distinguishing characteristic of plumeless thistle is the deeply serrated leaves.
Purple loosestrife is a perennial herb native to Europe. It grows 3-7 feet tall, with a dense bushy growth of 1-50 stems. Showy magenta flowers have 5-6 petals and bloom from July to September. Purple loosestrife has a large, woody taproot with fibrous rhizomes that form a dense mat. A single plant can produce over 100,000 seeds per year. Bushy mature plants can produce over a million seeds per year.
Saltcedar (tamarisk) is a perennial shrub or small tree, growing from 3 – 20 feet in height. This non-native plant originated in Eurasia, and was most likely brought to the United States as a beautiful ornamental plant.
Sericea lespedeza is an introduced perennial legume native to eastern Asia. Sericea was planted in the past to control soil erosion, provide forage for livestock, and provide cover and food for wildlife. From these plantings, it has spread by animals, and movement of contaminated hay to native prairies, forests and pastures and roadsides.
Spotted knapweed is a biennial or short lived perennial non-native noxious weed which originated in Eurasia. It grows from 1-4 feet tall, with the fine gray-green foliage and lavender flowers that bloom from June to September. Spotted knapweed grows on disturbed areas, overgrazed rangeland, roadsides, meadows and sandy soils in Nebraska.
Sheridan County Noxious Weed List
In 1976 Sheridan County landowners signed a petition to have field bindweed listed as a noxious weed in Sheridan County. By listing it as a “county added noxious weed”, landowners are required to control it. Bindweed is a noxious weed in eight of the eleven Panhandle counties.
In 2009, Sheridan County officially added houndstongue as a “county added noxious weed”. This requires landowners to control it on their property. Houndstongue is a biennial forb, which spreads only by seeds. Tiny reddish-purple flowers bloom up the branches, but seldom all bloom at once. The mature seeds of houndstongue are like Velcro. They stick to animals, tires, clothing, anything that passes by; spreading the seeds and starting new plants. Care should be taken to prevent the spread of houndstongue seeds to other areas in our county.
Scotch thistle was added to the Sheridan County noxious weed list in 2009. This giant thistle was spreading quickly through many areas in Sheridan County. It grows 2-10 feet tall, and has pinkish purple blooms between June and August. The foliage of Scotch thistle is grayish-green. The wavy leaves of the rosette are as much as 20 inches long and 6 inches wide, which is an identification factor. The stems are winged and very spiny.