Managing Rangelands rangeland: landscape of grasses and/or scattered trees - uncultivated & provides forage for large animals - gradient in precipitation, soil structure, topography

Rangelands -few inputs (contrast with cropland) forage: standing plant material (grasses, forbs, shrubs) that is edible Herbivory: grazing: consuming grasses & forbs browsing: consuming leaves/twigs of woody plants

* Manipulate grazing system of large herbivores for plant & animal production

* Maintain healthy rangeland by controlling # grazing livestock

* Rangeland Mgt & Wildlife

* Grazing on Public Lands & Endangered Species * Sage Grouse – 40 to 80% population declines (overgrazing, invasion of cheat grass)

* Rangeland Mgt & Predators / Wildlife Damage / Predator Control

Rangelands: 1) are a renewable resources if managed properly (ecosystem mgt) 2) important site of energy flow / nutrient cycling ruminants: herbivores with microbes in digestive system needed to digest cellulose (fiber) – transfer plant fiber to another energy source

Native vs. Domestic Grazing Systems Differences in selection & competition among species GrassForbs & Browse Cacti Horses100% Cattle90%10% Sheep40%60% Pronghorn6%83%11%

117 pronghorns = 1 horse 105 pronghorns = 1 cow 7 pronghorns = 1 sheep Selectivity among some N.American ungulates Pronghorn Sheep Cattle Bison Least Most

1)Grassland 2)Forest 3)Savanna 4)Chaparral / Desert Shrubland 5)Tundra Types of Rangelands * differences in climate (precipitation/ temperature), vegetation, fauna

Grassland (prairie, pampas, steppe, veld) Types of Rangelands -High productivity of forage -Grasses (family Gramineae) & forbs (broad-leaved) -Fibrous root, soil & water conservation, soil

Grazers:cattle, elk, bison, musk oxen,

Forest (shrub, temperate, tropical) Types of Rangelands -Compared to grassland: wetter conditions/lower fertility -Browsing habitat, but little grazing benefit -National Forest, Bureau of Land Mgt (BLM) lands

Browers:moose, pronghorn, goats, deer

Savanna (barrens) Types of Rangelands -Grasslands with scattered shrubs/trees -Influence of fire / transitional area

Chaparral / Desert Shrubland Types of Rangelands -arid climate -low-growing shrubs with deep-root systems -sensitivity to domestic grazing & riparian zones

Tundra Types of Rangelands -Low-growing vegetation, “tree-less” -permafrost -highly sensitive / native herbivores & migration

Intermediate feeders: sheep, caribou, burros

Rangeland Ecology * How does range management (grazing by domestic livestock impact the rangeland community in the long-term? * Excessive grazing & retrogression

Rangeland Ecology Wet rangelands, such as southern pine forest or the tallgrass prairie = quicker recovery after retrogression (<5 years)

Rangeland Ecology Drier rangelands, such as the Chihuahuan desert, slower recovery after retrogression (20+ years)

Rangeland Ecology Those plants that collectively occupy a site in the absence of severe disturbances – such as excessive grazing, fire and cultivation – are collectively referred to as the climax.

Grazing & metabolic reserve

Decreasers = high nutritional value, palatable, decrease with moderate grazing e.g., sideoats grama, little bluestem

Increasers= high nutritional value, less palatable, initial increase with heavy grazing pressure e.g., blue grama, Nebraska sedge

Invaders = low nutritional value, less (or not) palatable (poisonous), increase with heavy grazing pressure e.g., Canada thistle, ragweed

Grazing Systems Continuous Grazing: animals graze one area during growing season Pros = less labor, cheaper Cons = overgrazing possible, damage riparian areas Rotational Grazing: alternate grazing between multiple areas within or among growing season(s) Pros = better range condition, protect riparian areas Cons = more work, more planning

Precision Grazing Systems similar to precision farming GPS technology….map grazing units Develop grazing system plan accordingly….

Protecting Riparian Zones