The only way to accurately determine specific forage quality is through lab analysis of a forage sample. Reliable results depend upon submitting a good sample that truly represents the lot of hay that is being tested. Here are some tips for collecting a hay sample:
* Use a hay probe to collect the sample. Reaching into a bale of hay with your hand and pulling out some hay will not provide you with a good representative sample. A hay probe allows you to take a good cross section of the bale, getting a representative sample of both leaves and stems. Check with your county extension office about a hay probe. Many offices have one that can be signed out and used to collect a forage sample.
* Take cores from 15-20 bales within a lot of hay to get a more accurate average of hay quality. Small square bales should be sampled by drilling the hay probe into the end of the bale. Large round bales should be sampled on the rounded side of the bale. On large round bales, if the outer layer is weathered and not going to be eaten by livestock then pull away the weathered layer and sample from that point going in towards the core of the bale. It is important to try to mimic in your sampling what the animal is actually going to consume.
* A lot of hay can be differentiated by species, cutting date and location. For example, 1st cutting fescue hay vs. 1st cutting orchardgrass hay would be two different lots of hay, requiring two different samples submitted for testing. A first cutting orchardgrass hay baled on May 20th vs. a 1st cutting orchardgrass hay baled on June 20th are far enough apart in quality that separate samples should be submitted even though both are 1st cutting. In fact, if you look at the hay test results and dates from the Fairfield County samples in the previous article, 7-10 days can make a significant difference in hay quality and probably warrants a separate sample.
* A 1st cutting hay baled from a high fertility field vs. a 1st cutting hay purchased from a neighbor's rarely fertilized field should be considered as two different samples even if the hay was cut and baled about the same time and has similar species.
* As you sample, empty the forage cores into a plastic bag. Usually a 1 quart ziplock bag works well. Make sure the bag is clearly labeled. If you are sampling silage or baleage and there is going to be a time lag between sampling and delivery to whatever office may be sending off the sample for analysis, then refrigerate or freeze the sample.
Find a list here in PDF of some labs that can do a laboratory forage analysis: http://fairfield.osu.edu/topics/agriculture-and-natural-resources/flyers/Labs.pdf
Source: Rory Lewandowski, Extension Educator, Athens County and Buckeye Hills EERA