RS300
In Class
09-24-99
Objective 2. Develop a scenario where grazing management is essential to long-term sustainability. This scenario would help students evaluate/anticipate response of a system to grazing methodologies.
Situation 1: CITY OF FORT COLLINS – MEADOW SPRINGS
Meadow Spring Ranch is located about 20 miles north of Fort Collins. The area is owned by the City of Fort Collins and is leased to the Natural Fort Grazing Association. The city purchased the Meadow Springs area for municipal sludge disposal. The total area is over 20,000 acres. The area is grazed by domestic animals (cattle), based on a complicated bid/proposal system. The Butte (South pasture, Windmill pasture, Spring pasture), Antelope, Upper Middle Lewis and Lower Middle Lewis pastures are parts of one management unit.
The issue of grazing is not debatable at this time. Cow calf pairs graze the area from about May 1 till November 15. The other major herbivore is the pronghorn antelope. A few mule deer can be found in the area. The area is used by the Mountain Plover and is suitable habitat for the Swift Fox. No prairie dog colonies are found in this pasture. This pasture seems to be found in a narrow transition zone between the shortgrass steppe and the mixed prairie physiographic regions.
The city has asked the Natural Fort Grazing Association to develop a plan to insure sustainability of the resource. The need for management seems to be obvious, but the question of management for what has not been answered. Reports by Lauenroth et al. show that grazed shortgrass steppe is “healthier” than ungrazed shortgrass steppe. Historical grazing by cattle has reduced the abundance of tall species in wet areas. Cattle grazing has created uniform expanses of buffalograss is the swales. Pronghorn are using (hammering?) the saltbush in the winter. In most places, cattle management has been too successful eliminating early seral, low stature vegetation needed for Mountain Plover nesting habitat. In fact the best nesting habitat is denuded areas around windmills. The Swift Fox is a candidate for listing as a Category II species. All prairie dogs have been removed from the area. Late seral habitat, primarily for denning, has also been eliminated by cattle grazing.
The Association has retained my services to analyze the situation and provide them with a grazing plan. Because of the complexity of the situation, I told them the RS300 class would be happy to evaluate suggested grazing methodologies.
Andrea has prepared maps showing soils, range sites, elevation and some physical features, like roads, fences and steams. Also, Andrea has copied portions of the NRCS Range-Site, Condition Guide for this area for your perusal.
TASK:
1. Compare the median-year standing crop of different range sites. What is the absolute and relative difference in peak standing crop among sites? What accounts
for these differences?
2. Determine the total edible standing forage in each pasture (pounds).
The distribution (amount) of different plants in the NRCS Range Site Guide are allowable percentages; not percentage composition [note, numbers can sum to greater than 100%]. Composition is by air dry weight. These numbers represent composition as NRCS describes the “Historic Climax Plant Community, ” i.e., it is the plant community that developed on the site as a result of all the site forming factors. In reality it represents a community with little or no large-animal grazing pressure. Net Community Productivity = near Zero. The site represents the outcome of all the site forming factors, supposedly pre-European. That’s kind of a bogus definition. It’s nice to speculate which plants would occupy the site under no grazing pressure, but it probably never happened. Bottom line though is that “health” could be indexed to that standard, as long as we don’t place a value judgement on the current state based on the bogus “climax” state. Many stands (states) of vegetation can exist on a range site, with plants representing different portions of the “climax” community. Which is the “best” or “ideal” state is a value judgement.
TASK:
1. One of my goals is to manage in such a way as to reduce or stop some head-cutting in drainages and begin to heal some erosion gullies. In other words I see a
problem. Although some head-cutting is natural, head-cuts should continuously be healing. The gullies are found on the steeper slopes, e.g., >5 to 10 %.
Respond to this statement, you want to engineer a Loamy Plains plant community (some of which make up the head of the gully) to another plant composition.
The reason for this is to increase cover and structure to increase water infiltration and slow water acceleration and runoff. One of the plants, buffalograss, is
found in much greater abundance than desired; western wheatgrass in lower abundance. My real concern is the lack of western wheatgrass in the swales
[actually, these swales are not even mapped out – they are inclusions]. The same occurs on the LP site, but differences are less pronounced. Besides, Loamy
plains soils are not quite as fine textured as the swale soils. Should I first develop management strategies to deal with buffalograss or western wheatgrass?
2. Which biological/physiological/ecological process will you manage? What will be the indicators of system response? Which elements/attributes/relationships/
values in the ecosystem will you keep track of? What will be the evidence you were successful? Who will validate your success?
3. What are your action objectives and what will you do next?