Be Aware Purchasing Livestock Feed Containing Weed Seeds
Take precautions against spreading noxious weeds through transported livestock feed.
October 6, 2021 | View PDF
Due to the impacts of widespread drought on forage and hay production in North Dakota, most livestock producers are seeking feed resources to get animals through the upcoming winter.
The United States Department of Agriculture recently announced that the Emergency Assistance for Livestock, Honey Bees and Farm-raised Fish (ELAP) program will be expanding to cover feed transportation costs for those impacted by drought. Livestock producers in all North Dakota counties will be eligible.
Additional support for feed transportation is available through the North Dakota Department of Agriculture's Emergency Feed Transportation Assistance Program.
As feed resources start moving across the state, North Dakota State University (NDSU) Extension specialists warn of the potential to spread noxious and troublesome weed seeds.
Palmer amaranth has now been confirmed in both Grant and Sioux counties. Sunflower screenings merit particular attention, as contaminated sunflower screenings have been linked to infestations in six counties in North Dakota over the last 12 months. If purchasing sunflower screenings, be sure to ask the origin of the sunflowers.
Hay, grain and screenings all can carry noxious and troublesome weed seeds.
"Be sure to look at feed resources you plan to purchase with attention to weed seeds, and consider how you will manage the weeds," says Karl Hoppe, NDSU Extension livestock systems specialist at the Carrington Research Extension Center (CREC). "That cheap load of feed might turn out to be the most expensive feed-related problem you have encountered."
In one case, screenings had been fed to cattle and Palmer amaranth was detected in fields where cattle grazed and also fields where manure was spread as fertilizer.
"This serves as a reminder that grain screenings can be a major pathway of Palmer amaranth introduction into the state, especially if the screenings originated from areas of the country where Palmer amaranth is the most abundant weed," says Joe Ikley, NDSU Extension weed specialist.
Grain screenings, as well as hay, can carry viable weed seeds that may germinate in unusual locations.
"Where the screenings are unloaded can lead to the start of a weed infestation," Ikley adds. "These areas proliferate in feed yards that do not have fastidious weed control."
"When feeding livestock in pens, the manure should be contained and composted," says Mary Keena, NDSU Extension livestock environmental management specialist also based at the CREC.
When composted correctly and appropriate compost temperatures are attained, the weed seeds lose the ability to germinate. Search online for "NDSU composting animal manures" for instructions.
If livestock are going to be fed on pasture or hay land, NDSU Extension specialists recommend that producers use non-native areas where weeds can be easily spotted and treated.
"Feeding weed seed-heavy feeds on native rangeland adds both unnecessary seeds and nutrients which can benefit invasive grass species, such as Kentucky bluegrass and smooth brome, the following growing season," says Miranda Meehan, NDSU Extension livestock environmental stewardship specialist.
NDSU Extension specialists have several tips on how to manage feed and manure that may be contaminated with troublesome and noxious weed seed:
- Buy cleaned grain to help keep issues off the farm. However, purchased feed isn't routinely tested for weed seeds.
- Have screenings tested to determine the presence of weed seeds prior to feeding the screenings to livestock. Feeding whole seeds may perpetuate the problem. Some seeds, especially tiny, hard-shelled seeds from Palmer amaranth, can escape digestion by cattle.
- Grind the screenings so fine that the seeds are destroyed. For a small-seeded plant such as Palmer amaranth, aggressive grain processing is needed, and hammer milling usually is the best. The small black seeds are about 1 millimeter in diameter.
- Compost manure to reduce seed viability.
- Keep records of where feed resources are unloaded and fed.
For more information about noxious and troublesome weeds or manure management, contact the NDSU Extension agent in your county. Visit https://www.ndsu.edu/agriculture/extension/county-extension-offices to find the Extension office in your county.