1. My Horse University and eXtension welcome you to this live Webcast. Plants Poisonous and Harmful to Horses Krishona Martinson, PhD Equine Extension Specialist University of Minnesota

2. Meet our presenters: Krishona Martinson, PhD Equine Extension Specialist University of Minnesota Roger Becker, PhD Extension Weed Specialist University of Minnesota

4. Poisonous and Harmful Plants

5. Weed Control

9. Less palatable

10. Less nutritious

11. Lower yielding

12. Less dependable as a forage

13. Invasive

14. Poisonous

16. Poisonous and Harmful Plants

17. Weed Control

19. Eastern Black Nightshade

20. Common Cocklebur

21. Weed Seeds

22. Weed Control – mowing and herbicide (if needed) in spring

25. Hay/pasture would be less than 10% foxtail

29. Clinical signs include colic

30. Broadleaf herbicides – 2,4-D andor Dicamba

34. 0.25% body weight (2.5 pounds)

35. Affects liver

38. Wild Parsnip

39. Weed Control – mowing (difficult in first year) and herbicide application (if needed) in first year

41. Stems have purplish spots

42. Leaves have a lacy appearance

47. If pulling by hand, wear gloves andprotective clothing, as contact can cause severe blistering of the skin

49. Severe sunburn may occur throughskin contact, or in the blood vesselsdue to ingestion

52. Hoary Alyssum

53. White Snakeroot

54. Buttercup (Tall)

55. Horsetail

56. Brakenfern

57. Weed Control – mowing and herbicide application (if needed) in the fall (prior to flowering)

60. The roots are toxic at all times, evenwhen dry

62. Death, may occur within 30 minutes of theonset of signs

64. These clinical signs normally subside 2 to4 days following removal

67. Founder can be an issue with prolongedingestion or when stressed

69. Leaves have toothed edges andflowers are white

70. Found only in shady areas

72. Clinical signs include colic

74. Found mostly on wet, sandy soil

75. It is poisonous to livestock when eaten in largequantities

77. Found in open pastures, woodlands andparticularly on acid soils (under pine trees)

79. Mechanically controlled by frequentmowing. Chemically controlled by Ally(spot treatment only)

81. Foxglove

82. Rhododendron

83. Oleander

85. Do not put clippings into pasture

86. Do not put yew wreathes on boxstall doors

88. Most are associated with overgrown or escaped landscapes

91. Black Walnut

92. Maple

93. Oak

95. Damaged leaves pose the greatest risk

96. Do not plant around horses

97. Cyanide is the toxin

99. Affects the vascular organs

100. Clinical signs include stocking up andfounder

102. Signs of toxicosis include colic and/orred/brown urine

104. Ingestion of LOTS of acorns with greenhull still attached

105. Affects the kidney (tannins)

106. Clinical signs include colicPhoto Credit: ACC-CTC

110. An unknown mold converts the naturally occurringcumarol in the sweet clover to dicumarol

111. Horses may bleed if moldy sweetclover hay is asubstantial amount of a horse’s diet

113. Infestation of red clover with a mold(upper side of leaves) in hot humid weather(usually > 85 F)

115. Can cause liver damage

117. Herbicides alone will not result in a weed-free horse pasture

119. Do not over-graze

120. Over-seed thin areas

121. Fertilize

122. Mechanical Control

123. Mowing

124. Chemical Control

126. References Martinson, Hovda, and Murphy. 2007. Plants Poisonous or Harmful to Horses in the North Central United States (www.extension.umn.edu/horse) Martinson and Peterson. 2007. Managing Established Horse Pastures. (www.extension.umn.edu/horse/components/pasture.htm) Cornell Poisonous Plant Website (www.ansci.cornell.edu/plants/horselist.html)

127. Questions?

128. Thank you for attending this live web presentation! For more information about My Horse University and its online program, Please visit us at: www.myhorseuniversity.com Contact us! info@myhorseuniversity.com www.myhorseuniversity.com (517) 353-3123 My Horse University is a national online program based at Michigan State University in partnership with eXtension and Equisearch.