Hay Sample Tips
  • Identify a single 'lot' of hay. A hay lot should be identified which is a single cutting, a single field and variety, and generally be less than 200 tons. Don't mix cuttings or fields.
  • Choose a sharp coring device. Use a sharp coring device 3/8-3/4" diameter. Never send in flakes or grab samples. Corer should have tip 90 degree to shaft, not angled. Sharpen frequently. See list of probes at National Forage Testing Association website.
  • Sample at random. Walk around stack - try to represent all areas of the stack. Don't avoid bales or select certain bales. Choose bales at random.
  • Take enough cores. We recommend a minimum of 20 cores for a composite sample to represent a hay lot. Take more than 20 cores in highly variable lots, e.g. weedy fields.
  • Use proper technique. Sample butt ends of hay bale, between strings or wires, not near edge. Probe should be inserted at 90 degree angle, 12"-18" deep. On round bales, sample towards middle of bale. A greater number of core samples is better.
  • Not too big, not too small. Sample so that you produce about 1/2 lb of sample. Too-small samples don't fairly represent the variation in the hay lot. Very big samples (common with large length or diameter probes) cannot be easily ground by the labs. If a probe is too big or small to produce about ½ pound in 20 cores - get a different one! (list of probes on NFTA website)
  • Handle samples correctly. Seal Composite sample in a sealed plastic bag and protect from heat. Double bagging is beneficial, especially for DM measurements. Deliver to lab as soon as possible.
  • Never split samples without grinding. To test two labs, ask for your ground sample back to send to another lab. Unground samples are not a fair split. Use several samples to test average bias between labs. Don't work with labs that are unwilling to do this.
  • Choose a National Forage Testing Association Certified Lab. Some labs have volunteered to participate in NFTA's quality proficiency tests. To be certified, labs must match the true mean within an acceptable range of variation. NFTA labs have demonstrated their commitment to good results, are more likely to be interested in accuracy.