Observations On A Hayfield

By Gene Schmitz
MU Ext. Field Specialist in Livestock

I had the opportunity to observe a hay field on June 11 where we had conducted some fertilization research on a novel endophyte tall fescue stand from 2019 through 2023.

More on that later, but I wanted to share some observations.

The most striking thing to me was the lack of seedheads on the tall fescue.  I’ve also observed this in pastures as well.  Speculation is that the late freeze impacted cool-season grass growth and has contributed to this lack of seedhead formation.

The second observation was the presence of ergot bodies infesting some of the seedheads.  These form in response to warmer, wetter conditions and can impact many cool-season grass species as well as grain crops such as wheat and rye.  The normal seed is replaced with black fungal masses resembling mouse droppings.

Ergot bodies contain toxic alkaloids similar to those found in toxic endophyte tall fescue.  During the hay making process, many of these ergot bodies are knocked off the heads, but there is still potential for some to be wrapped up in the bales.  It is more probable that these are consumed in pastures that have headed out.

Ingestion of ergot bodies can result in many of the symptoms seen with consumption of toxic endophyte tall fescue.  Clipping pastures that have headed out and contain ergot bodies is the simplest way to try to reduce the chances of ingestion of these ergot bodies by livestock.

The final observation I made was the difference in grass undergrowth depending on the fertilization history of the plots during the 4-year trial ending in 2023.  It was obvious walking across the field where the plots receiving no to limited levels of nitrogen were located.  It was equally obvious where the plots received higher levels of nitrogen at 150 to 200 units of nitrogen per acre.

Plots that received higher levels of nitrogen fertilizer had much denser undergrowth compared to the plots receiving 0 to 50 units of nitrogen per acre.  This difference was easily observed three years after the research project ended.

So what does all of this mean?  This seems to tell the story that fertilization management in cool-season hay fields matters, especially when growing conditions are less than ideal.  As you harvest hay this season, look for areas of poor yield and compare those to areas of higher yield.  How has management differed between those areas?  If you have poor yield this year, instead of blaming weather, think about your overall management of hay fields.  Have they been soil tested in the last decade?  If so, have the fertilization and liming recommendations been followed on an annual basis?  Has the stand thinned so much the last 3 to 5 years that complete renovation is warranted?

Based on the amount of leafy undergrowth compared to the amount of stems and seedheads, forage quality might be better than expected, especially with late-harvested hay.  This would be a good year to pull some hay quality tests to see how the nutritional content of this years hay stacks up to past hay quality history.  These are just a few things to consider as you put up your hay crop this season.

If you have additional questions on these topics, contact me by email at schmitze@missouri.edu or call the Pettis County Extension Center at (660) 827-0591.