Reducing Ragweed in Pastures
By Noel Mues, Extension Educator,
Ragweed growth has exploded in many of our pastures during recent years. This major source of hay fever can reach 1'- 6' in height, depending on the taxonomy. There are three different kinds of ragweed: common ragweed, western ragweed and giant ragweed and all are responsible for ragweed allergy.
Under the right conditions, there's one characteristic of giant ragweed that you can't miss: namely, its height. It is not uncommon for giant ragweed to stand 6 feet tall or more. The stalk on such a plant will be thicker than a broom handle and may bear many large branches. However, giant ragweed is otherwise unremarkable, even as weeds go. It bears inconspicuous yellow flowers; nor does its foliage offer much interest.
Common ragweed is indigenous to
Timely spring rains have encouraged germination and seedling growth. Dry conditions during the fall contribute to seed development; and drought conditions during previous years weakened competition from desirable grasses.
Both, common ragweed, which is an annual, and western ragweed, which is a perennial, can be held in check by using similar methods of control. However, common ragweed is controlled more easily with grazing management or herbicides than western ragweed. Western ragweed has the ability to reproduce by rhizomes (underground stems) or seeds.
Research and observation both show that ragweed problems are greater in pastures that fail to maintain competition from a full leaf canopy of grass during late May through late June. If you experienced ragweed problems the past couple of years, look for tiny plants or seedlings underneath the grass during the next couple of weeks. Heavy grazing or haying during this time opens up the grass sward, letting seedlings and small plants grow rapidly.
Any management that develops and maintains a dense leaf canopy at this time helps reduce problems with ragweed. This includes increasing grass growth with fertilizer and thickening stands by seeding, but most important of all is to avoid grazing heavily in areas with ragweed problems. If you do graze heavily or cut hay, treating with herbicides like 2,4-D or Grazon or Milestone or Weedmaster after grazing or cutting gives good control of ragweed seedlings and small plants. And if ragweed gets away, shredding in September can reduce seed production.
It takes time, and a well-planned approach, to control ragweed. With proper grazing, appropriate use of herbicides and timely shredding it can be done.
All 4-H Youth who will be exhibiting beef, swine, sheep, dairy cattle or dairy and meat goats at County Fair, State Fair and/or Aksarben are required to be certified in Quality Assurance (QA). Clover kids, that exhibit livestock, are not required to be certified in Quality Assurance. Three options are being offered to become certified.
Online Course – A new online version is available to
Training Meeting – Quality Assurance Training events are scheduled as follows:
Date Time Town Location
Wed., June 6 7:00 p.m. Arapahoe Ella Missing
Wed., June 20 10:00 a.m.
Each session will last about 1& 1/2 hours.
Testing Out – Youth, ages 12 and over, have the option of “testing out” of the training. All testing will be done at the Extension Office. It would be best to call us in advance to make an appointment to do the testing.
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