Wintering on a soybean field?

[If_husband_asks_horses_are_fre]

My horses normally winter in a big grass pasture, but we’ve had a really dry year and there isn’t enough grass cover to turn them out there without killing off the pasture entirely. My dry lot is awfully small to keep the horses in long term. I have the option of electric fencing off part of a harvested soybean field and letting the horses out there to stretch their legs, but I can’t find any info on whether the residual beans and chaff would be a health issue for them. My plan would be to turn them out for short amounts of time with hay and then gradually start letting them out for longer periods. Has anyone done this?

Extra Info: My local extension office wasn’t a lot of help. Ditto for my vet, who is a wonderful vet, but really more of a cattle guy. If anyone wants to know, per my vet cows most definitely can graze on fallow soybean fields. But horses? Not sure… The field was sprayed with herbicide this spring but the chemical labeling indicated it would be ok for grazing after 14 days, so that should be ok. Their regular feed has soybean oil, so I’m hoping allergies won’t be a problem.

[NaturalSelection]

My neighbor pastures his horses on a harvested corn field every winter. I would be a little concerned about choke on corn, but he’s old-timey and no issues so far.

No advice for the OP on soy, but I’m very curious. I usually keep my horses on drylot over the winter, but I’m considering different ways to keep them more active. I could fence in 20 ac of hayfield but I’m worried about residual sugar for my EMS horse. If harvested soy is not harmful to horses then someday I might consider that instead.

[sherian]

It doesn’t look like there is much left plant wise after they harvest soybeans? I did feed soybean hull pellets as a substitute for beet pulp the year we had a major shortage.

[goodhors]

I am going to say the soybean field as pasture is a poor idea. Not something I would do. Green soybeans are unsafe for horses to eat. Not as sure about the stems and leaves being harmfull. They are legumes, being beans.

Horses WILL eat things they normally ignore when there is no grazing and they are bored. Even with plenty of good hay, they look for “green stuff.” I pull all my Milkweed plants around now for this reason. NOT going to tempt fate!

You will want to go further up the Extension Service ladder, by contacting your State land grant University, home of the Extension Service to ask your questions. They would have the State Vet College to ask or refer you to.

[Leather]

The question is how much raw soybean will be left in the fields, as it is bad for horses.

KER: Soy for horses facts and fallacies

However, raw soybeans should never be fed to horses because they contain a protein that inhibits the action of trypsin, an enzyme that initiates the breakdown of proteins into smaller molecules. Soybeans should be roasted or otherwise cooked before feeding so the trypsin inhibitor is denatured and triggers no ill effects on the digestion process.

Ruminants like cattle can break down the inhibitor so it’s not an issue for them.

The bean field next door was harvested yesterday and out of curiosity I took a look and some pictures.

Stubble left behind:

Immature pods with beans in the stubble:

Beans on the cleared ground:

If the stubble will be baled (it sometimes is for cattle bedding) that might help, but it’s hard to know how much raw bean they could consume.

[clanter]

just four soybeans per square foot is considered equivalent to one bushel per acre

that bottom photo appear have a lot

[NaturalSelection]

This board is a fantastic resource. Thank you!!

[If_husband_asks_horses_are_fre]

I wanted to add an update for anyone that might reference this thread later- I went ‘up the chain’ with the extension service and finally received this reply from Purdue University via Ask Extension:

My Question to them was worded as follows:
Is it safe to turn horses out on a harvested soybean field? They would still get their usual grass hay and grain and I don’t intend the soybean chaff to be their feed source, I’m just looking for a space for them to roam around and not be cooped up in their dry lot all winter. There are some scattered beans, but no spills or bean piles, and some whole plants at the edges that didn’t get picked up by the combine.
Their reply:
Yes, the soybeans would not be a health hazard. Soybean meal is a common additive to horse feeds (to increase protein) so any soybeans they happened to pick up would not be a problem. I am sure the horses will appreciate the extra space.
Just to be on the safe side, my husband will turn cattle out on the field for a few weeks before horses go out there. The cows do a remarkably good job of cleaning the scattered beans and whole plants.

[JB]

Raw soybeans aren’t healthy, are technically toxic, but a few here and there would be fine (because the dose makes the poison). There’s a reason that ALL soybeans are cooked/heated to some degree for any consumption by horses (and people).

[goodhors]

Sorry to say I don’t think they read your question well, did not note GREEN SOYBEANS on the ground which are dangerously NOT EDIBLE!

Soy bean meal is a COOKED product, as mentioned above, which changes the harmful parts in the beans. Michigan State University has said the raw, green soy beans are harmful to horses in their Extension Service brochures, Education programs for horse people, repeating this feed danger for YEARS!

[Leather]

Yeah that response missed the mark equating raw soybeans with soybean meal (which is heat processed).

But if you can turn cattle out beforehand like you said they should probably take care of any stray beans, so good solution!