Horse owners and admirers alike enjoy watching horses graze in green, lush pastures. But, the pretty view from the road or the kitchen window can be deceiving. That beautiful green could be weeds in their prime. Horses make their homes particularly susceptible to invasion by weedy species by primarily seeking out and eating grasses.
Due to their low palatability and nutritional value, weeds increase dependence on supplemental feed, and species like buttercup, tansy ragwort, and poison hemlock can cause poisoning and death.
The best way to deal with weeds is prevention. Maintain vigorous, healthy grass stands through proper irrigation and fertilization. Avoid over and undergrazing. While overgrazing might be an obvious strategy to avoid, undergrazing is just as important. Horses are selective grazers and, given the choice, will continually graze the same area if there is something there that they enjoy. A weed could be lurking in the tall grass they didn't eat, with a great opportunity to spread into the more heavily utilized areas. Use cross fencing and rotational grazing and focus on even use of a pasture. When there is more pasture than horses to graze it evenly, try periodic mowing.
If your horses will tolerate the company, consider introducing a friend. Different animals prefer different plants, and sheep or goats could be used to eat what the horses won't. They will actually seek out certain knapweeds and mustards to eat. This approach can help you avoid a situation where one kind of plant has the advantage over another.
Avoid introducing weeds. Get to know what they are, starting with your state or county noxious weed list. Examples, photos, and books are available through your county extension agent or weed inspector to help you with identification.
Once you know which plants are weeds, watch for them where you ride and trailer your horses. Trail rides and horse shows are not only wonderful recreation but also one of the primary vectors of weed spread. Parking lots of arenas, barns and stables are common sources of weed seed. If weeds are present, take the time before you come home to wash wheels, bumpers and under-carriages, brush manes and tails, and clean feet free of mud and seeds.
If you buy the hay you feed, seek out and use certified weed-free hay. The hay should come with an inspection certificate and an identifier such as a specific, unique string color. In the northwest, Wallowa County, located in northeast Oregon, has been a leader in the market. In March 2003, the Wallowa County Hay Growers Association formed to promote and provide premium and certified weed-free hay and straw. Soon after, the association was on-line with contact information for several members offering certified hay. Their website, www.certifiedwallowacountyhay.com, also provides an excellent model for the certification process. Malheur County has a similar program. Your local extension agent or county weed inspector should be able to help you find and contact a certified grower.
If weeds are present in the pasture, your local weed inspector can help identify specific species, determine toxicity and suggest treatment options for eradication.
Most important: remember that weed prevention is continual. Your horse pastures can be productive and beautiful with educated vigilance and thoughtful pasture management.
Erin Melville is a horse owner and rider. She is employed as Field Projects Coordinator for Wallowa Resources, a community-based non-profit organization in Enterprise, Oregon, dedicated to sustaining Wallowa County's economy and ecosystems.
1 Irrigate pastures to keep grass stands strong
2 Fertilize to maximize pasture health
3 Avoid under & overgrazing
4 Cross fence and rotate grazing
5 Introduce companion animals to even out grazing
6 Know your weedsidentify toxic varieties
7 Destroy toxic and spreading varieties
8 Avoid introducing new weeds
The www.certifiedwallowacountyhay.com website has a wealth of information about their hay certification program. Well worth a visit. You'll learn the standards for field inspections, identifying harvested forages, as well as the requirements applicants must fulfill to have their hay certified.
A handy chart gives the names of hay producers within the program and identifies which types of crops they grow (alfalfa, grass, wheat straw, and so on); how they package it; contact information; and information about how the hay is stored. Check it out at www.certifiedwallowacountyhay.com
The following weeds have been designated as noxious or undesirable in the Regional Weed Free forage Certification Standards, as set by Wallowa County Hay Growers Association. Likewise, we should all seek & destroy these pests.
1. Absinth Wormwood
2. Bermudagrass
3. Buffalobur
4. Canada Thistle
5. Common Burdock
6. Common Crupina
7. Common Tansy
8. Dalmation Toadlfaz
9. Diffuse Knapweed
10. Dyers Woad
11. Field Bindweed
12. Hemp
13. Henbane, Black
14. Hoary Cress
15. Horsenettle
16. Houndstonge
18. Jointed Goatgrass
19. Leafy Spurge
20. Purple Loosestrife
21. Matgrass
22. Meadow Knapweed
23. Medusa Head
24. Milium
25. Milk Thistle
26. Orange Hawkweed
27. Oxeye Daisy
28. Perennial Pepperweed
29. Perennial Sorghum
30. Perennial Sowthistle
31. Plumeless Thistle
32. Poison Thistle
33. Puncturevine
34. Quackgrass
35. Rush Skeletonweed
36. Russian Knapweed
37. Scentless Chamomile
38. Scotch Broom
39. Schotch Thistle
40. Silverleaf Nightshade
41. Skeletonleaf Bursage
42. Spotted Knapweed
43. Squarrose Knapweed
44. St. Johns Wort
45. Sulfur Cinquefoil
46. Syrian Beancaper
47. Tansy Ragwort
48. Toothed Supuge
49. Wild Oats
50. Wild Proso Millet
51. Yellow Hawkweed
52. Yellow Starthistle
53. Yellow Toadflax