Two new programs have been established to benefit producers and the environment, the cover crop program and the Natural Resources Conservation Service’s (NRCS) pollinator program. These programs support ecosystems health and enhance crop production and management. However, the discovery of Palmer amaranth in some fields has raised concern because its source has yet to be identified. This weed can seriously affect soybean producers who have been dealing with common pigweed for years. Until the source of Palmer amaranth is identified, farmers can protect themselves, to some degree, by being cautious when selecting their seed sources.
NRCS requirements for testing cover crops seed
Farmers have discovered that it can be a profitable option to participate in the cover crop program. Consequently, the Iowa State University (ISU) Seed Lab has seen a marked increase in rye seed testing from farmers who save their own seed or sell seed to other producers.
In Iowa, the NRCS requires farmers using home-grown seed to conduct warm (standard) germination tests and purity tests to determine percent Pure Live Seeds (PLS). For those intending to sell seed to others, a noxious weed exam must also be performed before seed commercialization. This test determines and quantifies the presence/absence of noxious weeds deemed noxious in the state before seed can be sold.
For more information on requirements for selling agricultural seed in Iowa, consult the Iowa Department of Agriculture and Land Stewardship’s Selling Agricultural Seed in Iowa: Selling Direct From the Farm Permit & Labeling Requirements. It is available on the ISU Seedlab Website at: www.seedlab.iastate.edu/files/IDALS2014_1.pdf, or write (Robin.Pruisner@Iowaagriculture.gov).
If you have a cover crop seed lot that needs to be tested, feel free to send it to the ISU Seed Lab for evaluation.
What can producers do to protect themselves against Palmer amaranth and other undesirable seeds coming into their fields via planting?
An especially frustrating characteristic of Palmer amaranth seed is that it can’t be easily distinguished from common pigweed seeds by visual examination.
Producers can choose one of two options to correctly identify Palmer amaranth seed. They can grow the seeds, because Palmer amaranth plants are easily distinguishable from common pigweed. Or, soon they will be able to differentiate the seed through DNA tests currently being developed in California.
A noxious weed exam requires the visual examination of a seed lot. When primary noxious weed seeds (such as Canada Thistle and quack grass) are found, the seed lot can’t be sold until the primary noxious weed seed is removed. When secondary noxious weeds are found in a seed sample, the seed lot can be sold only if the secondary noxious weed species are listed on the label. Pigweed is a common weed, so it won’t be listed on a bag label (tag), but the percentage weed seeds will be listed.
This situation will continue to evolve, however the following practices can aid individuals that need to ensure they possess weed-free seed for planting. 1) Take extra care to buy weed-free seed; 2) Ask your seed supplier to share information from your test analysis report (this option is especially effective, because all species of weed seeds found in the tested sample are listed in the sample analysis report); and, 3) remove the weed seed through the process of seed conditioning. Seed conditioning can effectively remove the undesirable Palmer amaranth seed, leaving the seed lot weed-free to use for the planting of future cover crops.
ISU Extension Photo