Check for Contaminants in Hay

By Christine Gelley

Making and feeding hay can be tricky business. After a long season feeding hay, livestock producers are getting a lot of experience judging hay by its appearance. The way hay looks and feels can be helpful for making assumptions about hay, but appearance, smell, and texture are just a few indicators of quality. It takes these factors plus a laboratory analysis to truly understand the nutritional value of hay.

Even with a hay test in hand, we should still use our senses of sight, smell, and touch to help evaluate quality because sometimes we can spot an unwanted contaminant in hay that a lab test would miss.

The following are hay quality indicators that we can pick up on using our senses to determine if hay is worth feeding to our livestock:

• Leafiness- Leaves are the most digestible portion of the plant, both for grasses and legumes. Leaves should be plentiful and attached to the stems. A greater presence of leaves in hay tends to be correlated to greater nutritional value for the livestock consuming it.
• Maturity- Maturity is the number one factor that impacts forage quality. As plants mature, fiber content increases and digestibility decreases. Over mature hay has many stems and many seeds with few leaves.

 Leafiness and maturity are hay traits that are set on the day hay is harvested.

• Odor- Bad smells indicate problems like spoilage and mold growth. Animals will refuse hay that smells bad. Bad hay may smell sour, musty, be dusty, or damp. If you don’t like how the hay smells, your livestock won’t either.
• Color- Color is not a reliable indicator of quality. Green hay is usually a sign of good curing conditions. However, assuming that green hay is better than brown hay, could be inaccurate.
• Softness- The texture of the hay is important for animal intake. Pokey or brittle hay will decrease intake. Look for weeds that have thorns, spines, or awns before feeding. These plant structures will not only contribute to lower hay intake but could also pose health threats to certain livestock species.
• Purity- Pure stands of the same species, or collection of species are important for marketing purposes. Pure hay is easier to fit into a feed program and to describe for sale.
• Bale Condition- Hay bales should be uniform size and shape for easier storage. Wrapped bales should be adequately covered for protection from the weather and to prevent spoilage.
• Penalties- Contaminants in hay may include poisonous weeds, mold, dirt, and trash. These greatly reduce the quality and value of the hay. If you are making your own hay, scout fields for trash before you mow hay. Wind, flood, littering, and broken machinery can lead to harmful contamination of hay and can damage equipment, with costly consequences. Scout for weeds each season and develop an integrated approach to weed control to promote desirable plants and reduce harmful plants in hay. If buying hay, scout for signs of trash and weeds before, during, and after feeding. Determining what plants are weeds and what plants are not can be a challenge after harvest. A great place to learn more about common weeds of Ohio is the online Ohio Perennial and Biennial Weed Guide which can be access at: https://weedguide.cfaes.osu.edu/

I hope we are closing in on the end of hay feeding season and that conditions post-drought will improve to allow for a productive hay season in 2025. Take these hay judging tips into consideration ahead of hay season to maximize the marketability and nutritive value of the hay you are preparing to grow and harvest this year.