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Posted 23 July 2007. Forage and Grazinglands. Hay Testing University of Illinois at Urbana-Champaign. www.aces.uiuc.edu Urbana-Champaign, Illinois (July 11, 2007)--Test, don't guess. That phrase applies not only to testing soil for nutrients and for soybean cyst nematode, but it also applies to testing hay for nutrients. Hay analysis plays a critical role in balancing livestock rations, it is an important aspect of buying and selling hay, and hay analysis can help producers decide which type of hay should be fed to various classes or production levels of livestock.
Proper sampling of hay is extremely important to assure an accurate analysis. As the old saying goes, "an analysis is only as good as the sample provided to the laboratory". Hay sampling produces more variation in results than does laboratory error. However, if sampling procedure is carefully followed, sampling variation can be reduced to an acceptable level, and the potential forage quality successfully predicted. The following are industry accepted guidelines for hay sampling. 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. Combinations of different lots of hay cannot be represented adequately by a forage sampling method. Thus, different lots should be sampled separately. Hay should be sampled as close to the time of sale or feeding as possible. Hay should not be sampled immediately after baling, rather allow the hay to go through the normal process of moisture lost known as a 'sweat'. Use a hay sampling probe or coring device. Never send flakes or "grab" samples, as these samples do not adequately represent the hay lot. A list of hay probes is available at the National Forage Testing Association web site: www.foragetesting.org Take a minimum of 20 cores for a composite sample to represent a hay lot. This is the same regardless of bale size or shape. With small bales, sample 1 core per bale; but with larger (i.e. 1 ton) bales, take 2-3 cores per bale in the center of the ends. Sample butt ends of hay bale, between the strings or wires, not near the edge. The sides or the top of the bale should not be sampled, since these cores will only represent one flake from a single area of the field, and additionally misrepresent the leaf-stem ratio. With round bales, sample on the rounded portion towards the middle of the bale on an angle directly towards the center of the bale. Sampling should be done so that about a one-half pound sample is produced for the laboratory. The sampler should ensure that the entire sample is ground by the laboratory. Seal the composite 20-core sample in a plastic bag and protect from heat. Double bagging is beneficial. Deliver or mail to the laboratory as soon as possible. Do not allow samples to be exposed to excess sun (i.e. in the cab of a pickup truck). Lastly, choose a National Forage Testing Association certified laboratory. A listing is available at the above-mentioned web site. Remember to test, and not to guess. If you have questions about this or other agronomic topics, please call your local U of I Extension office. In Ogle County that number is (815) 732-2191. Contact: |
