Poisonous Plants

1. PoisonousPlants Ms. Gottfried

2. Most likely you have them in your pasture… • HUNDREDS of plants that are common in North America are poisonous to horses. • Very few green pastures have no poisonous plants in them. • Luckily, there are a few good reasons why horses don’t eat most of them!

3. Why do most horses not eat them? • Thankfully, most are not palatable. • What horse wants to eat a small bitter plant when there is so much sweet green grass around? • Horses are HUGE • Because of a horses large size, it takes a lot more than one bite to reach toxic levels.

4. On the other side… • Some plants can be toxic even with a nibble. • It is important to recognize these plants visually. • To help prevent them in your own pasture • To recognize them when visiting other places

5. Bracken Fern(aka: brake fern, eagle fern) • A perennial fern that has triangular leaves that can reach 2-3 feet high. • Grows in clumps in woodlands and moist, open areas. • Grows all over North American except the desert climates.

6. Bracken Fern • Contains thiaminase, which inhibits absorbtion of thiamin (vitamin B1) • Necessary for nerve function • Causes neurological impairment. • Some horses actually develop a taste for Bracken Fern!

7. Bracken Fern • Symptoms: • Neurological dysfunctions due to Vitamin B deficiency. • Depression, in coordination and blindness • Treatment: • Large doses of thiamin over a few weeks if caught early.

8. Now you! • Yellow star thistle/Russian knapweed • Yew • Red Maple Trees • Water Hemlock • Oleander • Hemlock aka: poison hemlock, spotted hemlock • Tansy Ragwort • Johnson Grass/Sudan Grass • Locoweed