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Ada County Weed Pest and Mosquito Abatement
Ada County's 5 Worst Weeds - Scotch Thistle
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***IMPORTANT NOTE***
According to Idaho Code 22-2407, Idaho property owners carry the primary burden of controlling noxious weeds on their land. County Weed Superintendents may only treat noxious weeds on private property if the landowner fails to fully mitigate the situation. In such instances, the County will treat the noxious weeds and bill the property owner for the weed control efforts.
Scotch Thistle plants are on the increase in our county, and we need your help to control this noxious weed. Scotch Thistle is the largest of the thistles found in this region, and grows so tall that it's been mistaken for a tree from a distance. Some of these plants will get 14 feet tall, with leaves that can grow more than a foot wide. It shades out other vegetation near it and soon takes over the growing area. Scotch Thistle is a very prolific seed producer; a well-developed plant can produce dozens of flower heads, each with as many as 100 seeds per head.
Scotch Thistle is a biennial plant. During its first year of life it grows from a seed to form a rosette (which are blue-green in color and is covered with very fine hairs). Scotch Thistle rosettes can become two to three feet wide, and have spiny, winged stems. Also during this time, the plant concentrates its energy into forming a large tap root that will support its huge top the following season.
Herbicides can be used on mature plants to arrest growth and seed production, however it's more effective to treat Scotch Thistle when it is young and still in the rosette stage. Early spring and late summer are excellent times to use herbicides on this noxious weed.
The seeds are dispersed by the wind and can remain viable in the soil for several years. If you must treat an area for Scotch Thistle, you will need to monitor the sight for new sprouts for several years.
Scotch Thistle is particularly invasive, and few management practices can control the infestation. Several herbicides are effective in controlling this weed. Herbicide selection is done case by case, and Ada County Weed Control workers are doing everything to control this weed found on public lands.
For help controlling a weed control problem, or for clarification about using herbicides, feel free to call Ada County Noxious Weed Control at (208) 577-4646, or visit our office at 975 E. Pine in Meridian. Our office hours are from 7:30 a.m. to 5 p.m. Monday through Friday except holidays.
|
Ada County Weed Pest and Mosquito Abatement
Ada County's 5 Worst Weeds - Scotch Thistle
|
***IMPORTANT NOTE***
According to Idaho Code 22-2407, Idaho property owners carry the primary burden of controlling noxious weeds on their land. County Weed Superintendents may only treat noxious weeds on private property if the landowner fails to fully mitigate the situation. In such instances, the County will treat the noxious weeds and bill the property owner for the weed control efforts.
Scotch Thistle plants are on the increase in our county, and we need your help to control this noxious weed. Scotch Thistle is the largest of the thistles found in this region, and grows so tall that it's been mistaken for a tree from a distance. Some of these plants will get 14 feet tall, with leaves that can grow more than a foot wide. It shades out other vegetation near it and soon takes over the growing area. Scotch Thistle is a very prolific seed producer; a well-developed plant can produce dozens of flower heads, each with as many as 100 seeds per head.
Scotch Thistle is a biennial plant. During its first year of life it grows from a seed to form a rosette (which are blue-green in color and is covered with very fine hairs). Scotch Thistle rosettes can become two to three feet wide, and have spiny, winged stems. Also during this time, the plant concentrates its energy into forming a large tap root that will support its huge top the following season.
Herbicides can be used on mature plants to arrest growth and seed production, however it's more effective to treat Scotch Thistle when it is young and still in the rosette stage. Early spring and late summer are excellent times to use herbicides on this noxious weed.
The seeds are dispersed by the wind and can remain viable in the soil for several years. If you must treat an area for Scotch Thistle, you will need to monitor the sight for new sprouts for several years.
Scotch Thistle is particularly invasive, and few management practices can control the infestation. Several herbicides are effective in controlling this weed. Herbicide selection is done case by case, and Ada County Weed Control workers are doing everything to control this weed found on public lands.
For help controlling a weed control problem, or for clarification about using herbicides, feel free to call Ada County Noxious Weed Control at (208) 577-4646, or visit our office at 975 E. Pine in Meridian. Our office hours are from 7:30 a.m. to 5 p.m. Monday through Friday except holidays.