Sunday, April 22, 2018

Exclosure

Teepee Grass Exclosure, Little Missouri National Grasslands, ND. Photo 9/15/08.Exclosures are plots of land that have barriers that prevent certain species from entering the plot. In western North America, the excluded species are usually domestic grazing animals such as cattle, horses, and sheep. In scientific studies, an exclosure is established as a baseline to which the rest of the surrounding landscape can be compared. This, in turn, shows the effects of grazing or browsing animals upon the environment. In centuries past, the barriers were made of stones and wood but this changed with the invention and mass production of barbed wire in the late 1800's. 
There are many exclosures in western North America. Some examples: The Lamar Exclosure is in Yellowstone National Park in Wyoming, east of the Lamar Ranger Station on the north side of Lamar Valley. Established in 1957 to restrict shrub browsing by elk and pronghorn antelope, the exclosure saw an increase in diversity, size, and range of shrub species over the decades. Today, the exclosure contains a grove of quaking aspen; only aspen seedlings are found outside of the exclosure. This aspen suppression is attributed to herbivory, the browsing of elk. Then there is the Quinn exclosure, southwest of Quinn, South Dakota on the Buffalo Gap National Grassland. It was set on a north-facing side slope in mixed-grass prairie. Today, the exclosure hosts a thicket of chokecherry, plum, green ash, buffaloberry and other shrubs while outside of the exclosure, where cattle graze, grasses and forbs dominate and few shrubs are found. The Flagstaff Exclosure is on the Lewis and Clark National Forest south of Checkerboard, Montana, in the Castle Mountains. Dense tufts of rough fescue comprise 50% of the cover in this exclosure while outside of the exclosure, where cattle graze, rough fescue comprises only 6% of the cover. This is a recurring theme. 
Originally, North America was open range. Herds of wild animals were free to migrate. In the late 1800's, the bison and other ungulates were virtually exterminated and replaced with European cattle. The cattle occupied the bison niche and, at first, were free to migrate like the bison. However, as farming operations were established, cattle encroached on the farms and ate the crops. Disputes arose. Farmers and cattlemen fought over land rights. This gave rise to the need for fencing to exclude the cattle. Wood and stones were scarce and expensive, so the relatively inexpensive, newly invented barbed wire was strung across the open range. This conflict simmered for years and many of you may recall that it boiled over on the set of the movie Oklahoma when a brutal fistfight erupted between farmers and cowmen, a grisly spectacle made all the more horrific as the bystanders - women, children, and the elderly - heartened the brawlers with festive music and dancing. 
This land is my land. 
They sang:

The farmer and the cowman should be friends.

Oh, the farmer and the cowman should be friends.
One man likes to push a plough, the other likes to chase a cow,
But that's no reason why they cain't be friends.

They should, but would not. Now, this fight was not sanctioned by any athletic federation and, as a result, there was no boxing ring. There are three ropes around a boxing ring, much like the wires on a barbed wire fence, however, there are no barbs on the ropes and none are electrified at this time. Why the ropes? A newcomer to the spectacle might reason that the purpose of the ring is to prevent the boxers from escaping and beating up the people in the audience. Another might reason that it is to keep the audience from storming the ring and beating up the contestants, much like European soccer. So the fans debate: Which directional movement do the ropes prevent, into the ring or out of the ring?  
This helps us to understand where the Louisiana Territory settlement went wrong. Which directional movement do fences prevent? Originally, fences were strung to exclude grazing animals, preventing animals from assaulting the croplands. But this changed with the expansion of agricultural lands; fences were strung to include grazing animals, both wild an domestic. In the case of wild animals, especially bison and pronghorn antelope, they were always included or confined to a relatively small, relatively wild preserve, which prevented humans from assaulting the animals. Thus, the function of the barrier inverted, from exclusion to inclusion, reversing flow like the mighty Chicago River. This has created a plethora of rural zoos across the globe, caged wildlife zones, animal enclaves, where wild animals are not free to migrate and, at best, are managed much like cattle, manually rotated from pasture to pasture or culled when they escape or exceed grazing capacity. 
Those three exclosures shown in the photos, they are exclosures within exclosures, really, and they have demonstrated that the animals in the greater exclosure are exceeding the carrying capacity of the land. In recent decades, we have observed the ascent of another species that has rapidly exceeded the carrying capacity of the land, expanding its range, population, and consumption at an unsustainable rate, eliminating other species and habitats and degrading ecosystem health. It ranges across all barriers, is found in every partition. We would propose an enclosure for this species, to allow recovery of the remnant ecology and free range of wild animals, but it owns the patent for the barbed wire and we would expect that the species, finding itself competing within a confined space, would resort to blows. 

https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1764&context=nrei

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