Cover Crop Seed Cautions
With harvest nearing many farmers are beginning to look at cover crop seed supplies. Depending on supply and demand some folks may choose to purchase "bin run" seed to help save on cost. Rightly so, cover crops are not a cash crop and buying seed from a local supplier can often be easier to handle and may sometimes be cheaper. But there are few considerations to keep in mind, if you have an NRCS contract for cover crops they are going to need a seed tag. Seed tags contain vital information required by law, things like percent of noxious weeds, germination rate, and amount of hard seed. (See example seed tag below)
NRCS has a "pure live seed requirement" meaning that they will only issue payment on actual live seed, they are not paying for foreign matter, non viable seeds, or weed seeds. According to NRCS here is the formula they use to calculate PLS (%Germination +% Hard Seed)(% Purity) = % PLS
If you have specific questions about payments based on PLS contact your local NRCS field office.
If you are for sure purchasing "bin run" grains there are several inherent risks associated with this practice:
Protected varieties Be sure the seed you are purchasing isn't protected by the 1994 Plant Variety Protection Act. Most species used for cover cropping aren't going to be affected by this but as the purchaser you must do your part to ensure you are not breaking the law.
Lack of information As stated earlier in the article, local growers may not submit their seed to lab testing. You could choose to do this on your own if the seller allows it.
Weed seeds The percent of weed seeds is something that should be on a seed tag and would show up on a test by any seed improvement lab. It cannot be stressed enough, do not subject your farm to unnecessary introduction of noxious weeds.
Calculating Seed Rates for Conservation Plantings: https://www.nrcs.usda.gov/plantmaterials/etpmctn10736.pdf
Pioneer Seeds, Bin Run Vs. Non Bin Run https://www.pioneer.com/us/agronomy/bin-run-soybean-seed-cropfocus.html
Guide to Understanding Seed Tags https://www.nrcs.usda.gov/plantmaterials/ndpmctn12317.pdf
Penn State, Bin Run Seed Associated Risks https://extension.psu.edu/bin-run-seed-associated-risks-for-soybean-production