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Toxic Plants, Part II

Sneaky plants you think are safe


   Did you know that many plants you FEED your horses are actually listed as "Poisonous"?  Think carefully. What do you feed in your hay that would potentially harm your horse? What's REALLY in you hay? Horrible weeds? Nope. Your HAY!

     1. Fescue grass (common lawn grass) is designed to fatten cattle. Often also fed to horses, but to get grasses to fatten cattle, they have to either be high in protein, fat or sugars. Horses don't tolerate sugars well and Fescue is rampant in sugars. Generally, cool season grasses are loaded with more sugars than warm season grasses. Fescue easily triggers laminitis, colic and certain varieties will cause reproductive issues for mares. The sugars cause metabolic problems. There is a fungus "endophyte" that contributes to the grass's hardiness that also causes preterm birth, thickened or retained placentas and problems with lactation in mares. You can get "edophyte" free varieties but they tend to be less hardy. My main concern is that it is one of the highest in sugars. It's so well known for triggering lamnitis that in cows they call it "Fescue Foot" . It CAN be used for horses, but try to get stemmy, more mature cuttings and do not feed to horses prone to hoof or weight issues. Soaking with water before feeding will remove some sugar. 

2. Brome-also a cool season grass, it's full of sugar, but does not have the endophyte issue that fescue has.

3. Asiklike Clover-Often tainted with a fungus, will cause sever "Slobbers" In horses. The fungus irritates the oral mucosa triggering excessive drooling that appears to be slimy water pouring out of the mouth. There is potential for dehydration, not to mention the usual colic/lamintits risk.

4. Cockle Burrs- If you ever find them in your hay, try to remove the plants. Most horses will avoid eating them in favor of grass, but this helps the plant take over certain areas and horses that are really hungry may nibble on the plant or consume them in hay.  They could potentially cause in-coordination, colic and even death if consumed. Again, most horses won't eat them, but if there isn't enough food, they may try them.

5. Bermuda grass-Now this one is actually a healthy grass to feed as hay and forage. It's low in sugars and is great for laminitic horses UNLESS it's infected with "Ergot" which is, you guessed it, a fungal infection of the grass. It  can cause strange neurological symptoms such as head tilting, shaking and even abortion in mares. Infected grass has blackened and red seed heads, but healthy, safe grass will be the normal green seed-heads. Once the infected grass/hay is removed from the diet, symptoms reverse.

   Please note, that fescue and brome, and other cool season grasses increase in sugar content with the weather. Drought, cold snaps, mowing and overgrazing makes the grass not utilize the sugars it's producing by not growing, so the grass is richer until it is used up in growth. Also, levels begin to rise as the day goes on, and peak sugar is reached from 4pm to dusk. The lowest sugar levels are generally around dawn, when the grass has depleted it's sugars by growing. So, grazing from noon on is the worst time of day. Cold after sunny days also increases sugar content. Watching the weather helps prevent laminitic attacks. Grazing at night after dusk, through dawn is your best bet. Also, when your hay was cut will affect how much sugar is in it. You can have it checked by your county extenstion office for a few dollars so you know how to supplement accordingly or what not to feed to your IR horses.


*Sources include Equinenest, Wickipedia, and "Horse Owner's Field Guide to Toxic Plants" by Sandra M. Burger.