In a paper published in Rangeland Ecology & Management, titled ‘Potential spread of cheatgrass (Bromus tectorum) by feral horses (Equus ferus caballus) in Western Colorado’ by Sarah King, Kathryn Schoenecker, and Daniel Manier, wild horses are alleged as the problem in regard to the spread of invasive species plants and grasses.
It is a fact, native species wild horses are evolved re-seeders of native plants and grasses in North America, and invasive species ungulates (cattle and sheep) are not.
This is one of many reasons why wild horses should not be managed on the landscape commingled with cattle and sheep, and must be managed in separate remote ‘designated’ critical wilderness areas (true wilderness vs. traditional grazing lands) in a manner that is ecologically and economically appropriate.
More about wild horse ecology here.
In most ‘critical’ or ‘designated wilderness’ areas — where in most cases there is no cheat grass (yet), because it hasn’t yet been imported into these areas by livestock producers — horses are the ideal wildfire grazers, and reseed native species plants and grasses as co-evolved keystone herbivores.
In areas that have been long-used (up to 300-years in some areas) for livestock grazing, where cheat grass (and other invasive weeds, such as Yellow Star Thistle, Centaurea solstitialis L.) were introduced and spread by livestock producers feeding hay — distributing it over the landscape — that was baled in valleys filled with invasive weeds and grass, and then imported into other areas to augment livestock feeding, we find extensive spread of invasive weeds and grasses that resulted from seeds distributed by birds and the wind.
The introduction and spread of invasive species plants and grasses from contaminated bales of hay being hauled into remote areas for livestock was the genesis of the spread of invasive species plants and grasses. From there, the seeds spread, and that practice still continues in many areas today.
It’s clear, the problem was not initiated by wild horses.
William E. Simpson II is a naturalist, author, and conservationist living in the Soda Mountain wilderness area among the wild horses that he studies. Learn more at Wild Horse Fire Brigade.