I'm not a REAL botanist; I just play one on Blogger

For the past few months I've been taking photos of  plants toxic to horses. Here's a good, informative site for plant identification including some details on toxicity.  Ohio Biennial and Perenial Weed Guide . I'm just going to use common names for ease of posting. Most horses and livestock will avoid these plants, but young or curious stock may sample, plants could be ingested if other non-toxic forage is not available, they could be baled in hay, or certain hebacides if not applied correctly may make the plants more palitable and increasing nitrate levels in all dying plants, not just the toxic ones.

I want to note that many herbicides that are labled safe for livestock 24 hours to even hours after treating may contain a somwhat fine print precaution about making deadly plants more palatable, and over time, livestock can build up toxicity of the herbacide itself.  For the goods on that visit these sites: EPA publication , Penn State argricultural extention , and Merck Vet manual pet health--herbicide poisoning

So, for now, heres a few photos to start, with more to come in other posts. Below is  Poison Hemlock, one of the deadliest, like water hemlock, it grows in moist areas and can become quite tall. Where I photographed this, there were stands at least 6ft tall and 2 to three feet thick, growing along a creek bed. Early growth looks like a lovely low growing fern-like plant So don't go transplanting it to your garden!  All parts of the plant are most toxic during early spring and can cause immediate death. If baled in hay, it can lose some potency, but depending on volume baled and eaten can also cause poisoning, possibly fatal.

Poison Hemlock

Another common one: Horse Nettle, one of the various nightshades. Below is an excerpt from  Equus mag... how toxic is this weed? 

 "Horse nettle, like many plants in the nightshade family, contains solanine, a glycoalkaloid that irritates the oral and gastric mucosa and affects the autonomic nervous system, which controls various internal organs. The glycoalkaloids act on the digestive system to cause excessive salivation, colic and diarrhea or constipation. These signs may be followed by depression, weakness, depressed respiration, dilated pupils, collapse and death if horse nettle is eaten in large amounts. - See more at: http://equusmagazine.com/article/how-toxic-is-this-weed#sthash.vwvc6xHm.dpuf "

Horse Nettle

Horse Nettle flower