Cover crops and witchcraft

Every once in a while, I can appreciate a good scare, but fear is not my preferred state of emotion. I think many farmers can agree that unwanted surprises and unexpected outcomes are not welcome in most crop and livestock systems, either.

Spooky and eerie are two words that don’t typically frequent my vocabulary, but it’s hard to ignore the upcoming holiday when Halloween candy has been stocked on grocery store shelves since July 5. To be sure, I don’t personally consider Halloween a holiday, nor do I participate in any related festivities, but I do get a kick out of some superstitions and scary stories.

For instance, I’ve started making nice with my neighbor’s black cat, willing it not to cross my path. And I was on the lookout for lunatics during the full moon last week. So, when I came across an excerpt from the second edition of “Capturing Sunlight” by Woody Lane on the connection between forage crops and the Salem Witch Trials, I had to keep reading.

Lane sets the scene for winter 1692 when an outbreak of convulsive hysteria afflicted a large group of young girls in Salem, Mass. There seemed to be no other explanation for the bizarre behavior other than witchcraft, for which 20 people were executed. Although accusing suspicious characters of witchcraft and having them hanged in the town square wasn’t a new practice by the Massachusetts Puritans, the outstanding number of offenders named during this particular event is what made the Salem Witch Trials stand out in American history.

So, where do forages come in?

An eye on cereal rye

In 1691, farmers near Salem recorded warm and rainy weather during the growing season. Lane writes the primary crop in the area at the time was cereal rye, which happens to be the most susceptible small grain to ergotism under those conditions. The ergot fungus infects grass species and grows into the plants’ reproductive tillers. Then, the parasite destroys the ovary, and what would have otherwise become a grain seed is replaced by a dark, elongated mass called a sclerotium.

Ergot poisoning is prevalent in livestock when animals consume infected seedheads, such as when they graze cover crops like cereal rye. Not only does the ergot fungus infect tillers and reduce yield potential, but it also produces more than 20 toxic alkaloids — most of which are vasoconstrictive. Lane notes affected animals can exhibit excessive salivation, incoordination, extreme excitability, vomiting, scours, convulsions, and dry gangrene in hooves, tails, ears, and teats.

One of the ergot alkaloids, isoergine, has a chemical structure similar to lysergic acid diethylamide, or the psychedelic drug LSD. Following the timeline of when cereal rye grain in Salem would have been threshed and ground into flour, one might suggest the mass hysteria that shook the small town in New England could have, in fact, been caused by bad batch of ergot-infected bread. In humans, ergot poisoning can create symptoms like numbness, spasms, cramps, convulsions, and a crawling sensation under the skin — many of the ailments that the young girls exhibited and complained about before being put to death.

Ergotism and grazing

Although this theory points to grain consumption by people, ergot poisoning can occur in forage systems as well. It is most common in the spring when livestock are turned out to graze cover crops that were seeded after row crop harvest in the fall. Following cereal rye in descending order, winter wheat, barley, and triticale are also susceptible to ergotism. Farmers may also harvest these cover crops for silage, or if possible, use them for an early cutting of hay.

Lane notes an uptick in what seems to be ergot poisoning has plagued livestock in his state of Oregon in recent years, and similar reports have suddenly sprouted up across the country. Despite the number of cover crop acres on the rise, the fact that more farmers are planting small cereal grains may not tell the whole story. It might also have to do with the way they are planting them.

Mature ergot sclerotium eventually disperse from seedheads and lie dormant in the soil. In tillage systems, these spores are buried deep enough in the soil profile that they are no longer threatening to forage production. However, as Lane states, no-till farming creates an ideal environment for the ergot fungus to survive and infect the next crop in the rotation.

Although the benefits of no-till abound regarding soil structure and reduced erosion, the practice may cause ergotism to prevail in cover crop stands and grass systems. In tandem with a greater adaptation of no-till, Lane states laboratories in Oregon have confirmed more cases of ergot contamination, and he claims other universities are publishing a growing amount of information about it.

With that said, there is no cure for ergotism in livestock. Lane explains veterinarians can only treat animals to reduce discomfort and minimize symptoms. Therefore, the best piece of advice to avoid ergotism is just that — avoid it. Monitor cover crop stands that are used for grazing and remove animals from the field as soon as possible if plants exhibit the rodent dropping-like sclerotium masses where there should be a grain seed.

Craig Roberts with the University of Missouri has recommended cutting hay early before ergot bodies develop. In this instance, the extension forage specialist emphasized ergot poisoning in tall fescue. Waiting to cut hay later in the season can also curb ergot poisoning, and the disturbance from baling may shake ergot bodies from seedheads, but doing so will likely reduce forage quality and put other field operations behind schedule.

Hopefully, this bit of dark history didn’t scare you out of planting small cereal grains or discourage the implementation of no-till. Rather, it should serve as a reminder of the potential consequences that any practice could have on crop production and livestock performance. And instead of thinking about witchcraft and hysteria the next time you hear a retelling of the Salem Witch Trials, perhaps you’ll think about hay and forage.