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27-650: Pawnee National Grassland is a United States National Grassland located in northeastern Colorado on the Colorado Eastern Plains . The grassland is located in the South Platte River basin in remote northern and extreme northeastern Weld County between Greeley and Sterling . It comprises two parcels totaling 193,060 acres (78,130 ha) largely between State Highway 14 and the Wyoming border. The larger eastern parcel lies adjacent to

54-559: A fungus that was introduced accidentally from Europe. Limber pine mortality is high in many areas throughout its range, except Arizona , where it has not yet been found. However, there is little hope of controlling the blister rust in existing trees. Research is under way, locating and breeding from the occasional naturally resistant limber pines, and by studying the resistance mechanisms of the European and Asian white pines (e.g. Swiss pine , Macedonian pine ), which are strongly resistant to

81-529: A large quantity of water. The grassland is a part of the short grass plains of North America. The best example of this ecosystem are preserved around the Pawnee Buttes where grazing and intensive agriculture have had less impact. There are eleven vegetation zones represented with the most unique being the scarp woodlands on the north face of the buttes. Typical of higher elevations, there are limber pines and relicts of an ice-age forest. The wildlife of

108-552: A tributary of the South Platte. The western unit is largely drained by Crow Creek. Camping is available at the Crow Valley Recreation Area northwest of Briggsdale. The grassland contains several hiking trails, including one that allows foot access to the Pawnee Buttes , the most notable geologic feature of the grasslands. Bird watching is a popular recreational activity for day hikers, especially at

135-512: Is available from a Cretaceous period aquifer . Three springs are in the vicinity of the buttes: Nelson Ranch 1 mile (1.6 km) north, old Linglebach Homestead 1 mile (1.6 km) south, and an arroyo 0.51 miles (0.8 km) west. The main access to the aquifer is by windmill pumps. The aquifer is recharged from the west and flows eastward. There are Tertiary and Quaternary aquifers which are recharged by precipitation and seepage from streams. The Brule Formation , where available provides

162-516: Is lightweight and soft. Pinus flexilis is typically a high-elevation pine, often marking the tree line either on its own, or with whitebark pine ( Pinus albicaulis ), either of the bristlecone pines , or lodgepole pine ( Pinus contorta ). In favorable conditions, it makes a tree to 20 metres (65 feet), rarely 25 m (80 ft) tall. On exposed tree line sites, mature trees are much smaller, reaching heights of only 5–10 m (15–35 ft). In steeply-sloping, rocky, and windswept terrain in

189-617: The Chalk Bluffs , a raptor nesting site. Recreational activities on the Pawnee Grasslands have been somewhat curtailed over the last 10 years due to the discovery of extractable oil and natural gas. According to the US Forest Service, there are 63 active vertical oil and natural gas wells, and less than 3,000 acres of the 193,060 acres is protected from drilling. The grasslands is a joining of two soil types. In

216-458: The Dust Bowl . The communities of Keota and Purcell are located within the grassland. The town of Grover is located directly between the two large parcels of the grasslands near Crow Creek . Briggsdale sits at the southern end where State Highway 14 and State Highway 392 meet. State Highway 71 traverses the eastern unit north of Stoneham . The eastern unit is drained by Pawnee Creek ,

243-736: The Transverse Ranges in Southern California . Continuing south the species is found in the San Jacinto Mountains , Santa Rosa Mountains , and Hot Springs Mountain of the Peninsular Ranges . There are small disjunct populations in eastern Oregon , in western North Dakota and Nebraska , and in the Black Hills of South Dakota . It is found at a wide range of altitudes depending on

270-545: The limber pine , is a species of pine tree in the family Pinaceae that occurs in the mountains of the Western United States , Mexico , and Canada . It is also called Rocky Mountain white pine . A limber pine in Eagle Cap Wilderness , Oregon , has been documented as over 2,000 years old, and another one was confirmed at 1,140 years old. Another candidate for the oldest limber pine

297-523: The Rocky Mountains of southern Alberta, limber pine is even more stunted, occurring in old stands where mature trees are consistently less than 3 m (10 ft) in height. One of the world's oldest living limber pine trees grows on the banks of the upper North Saskatchewan River at Whirlpool Point in Alberta. Recent measurements give a maximum girth of 185". In 1986, a core sample 10 cm

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324-566: The average size of a national grassland is 191,914 acres (77,665 ha). The largest, the Little Missouri National Grassland in North Dakota, covers 1,028,784 acres (416,334 ha), which is approximately the median size of a national forest. As of September 30, 2007, the total area of all 20 national grasslands was 3,838,280 acres (1,553,300 ha). The catastrophic Dust Bowl of the 1930s led to

351-628: The borders of both Nebraska and Wyoming . It is administered in conjunction with the Arapaho - Roosevelt National Forest from the U.S. Forest Service office in Fort Collins , with a local ranger district office in Greeley. The grassland is in an especially depopulated area of the Great Plains . It saw limited cultivation in the early 20th century but was withdrawn from farming after

378-417: The bristlecone pines, which share five needles per fascicle but have a semi-persistent sheath. Distinguishing limber pine from the related whitebark pine ( P. albicaulis ), also a white pine, is very much more difficult, and can only easily be done by the cones. In limber pine, the cones are 6–15 cm ( 2 + 1 ⁄ 4 –6 in) long where the species overlap, green when immature, and open to release

405-787: The creation of the Soil Conservation Service in 1933. This and subsequent federal laws paved the way for establishing national grasslands. The smaller Midewin National Tallgrass Prairie , created much later and east of the Mississippi River , is technically not a "National Grassland", as it was formed under different legislation, but it is managed by the Forest Service like one, as a unique prairie resource. Download coordinates as: Pinus flexilis Pinus flexilis ,

432-407: The disease. The tree has also been damaged by bark beetle epidemics, particularly at drought-affected low elevations. The popular cultivar P. flexilis 'Vanderwolf's Pyramid' is widely available as an ornamental tree for gardens . 'Vanderwolf's Pyramid' derives from P. reflexa , though it is usually listed in nursery catalogs under P. flexilis . The Southwestern white pine is popular as

459-512: The east are prairie soils that are deep, and dark or reddish. From the west are chernozems of a chestnut, becoming brown. The chestnut soils are the dominant type across the areas. These soils develop in semiarid climates with 15 to 20 inches (38 to 51 cm) of rain annually. They are associated with buffalo grass and blue grama . Around the buttes , the soils are most likely brown soils which are characteristic of cool, semiarid condition and are evidenced by short grasses and shrubs. Water

486-649: The edge of the Great Plains . Those four are in southeastern Idaho , northeastern California , central Oregon , and a reserve in Illinois . The three national grasslands in North Dakota , together with one in northwestern South Dakota, are administered jointly as the Dakota Prairie Grasslands . National grasslands are generally much smaller than national forests – while a typical national forest would be about 1,000,000 acres (400,000 ha),

513-496: The grasslands is best represented near the buttes, with pronghorn , deer , bison , prairie dog , coyotes , black-tailed jackrabbit , and numerous rodents . Nesting birds include the golden eagle and prairie falcons . Wildflowers bloom from April through September. The best locations for viewing wildflowers are near rocky outcrops or wet potholes, such as are found near the Pawnee Buttes . United States National Grassland All but four national grasslands are on or at

540-446: The latitude, from 850 to 3,810 m (2,790 to 12,500 ft). In the northern half of its range, it grows in the montane zone near the lower tree line ; in the middle of its range between the 45th and 40th parallels , it grows on windswept sites in the montane and subalpine zones ; and in the southern part of its range, it grows mainly at high elevations in the subalpine zone near the upper tree line. It can more often be found at

567-527: The northern Rockies and the Sierra Nevada east slope. The most useful clue here is that limber pine needles are entire (smooth when rubbed gently in both directions), whereas Western white pine needles are finely serrated (feeling rough when rubbed gently from tip to base). Limber pine needles are also usually shorter, 4–7 cm ( 1 + 1 ⁄ 2 – 2 + 3 ⁄ 4  in) long, while western white pine needles are 5–10 cm (2–4 in), though

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594-602: The outer fringes of a forest than in the forest itself. Pinus flexilis is an important source of food for several species, including red squirrels and Clark's nutcrackers , the latter being an important distributor of seeds. There is evidence that limber pines co-evolved with Clark's nutcrackers, which are the primary dispersers of the seeds. In a relic, low elevation population, seeds are also dispersed by small rodents. American black bears and grizzly bears may raid squirrel caches for limber pine nuts. Squirrels, Northern flickers , and mountain bluebirds often nest in

621-635: The ranges overlap. The largest part of the limber pine's range is in the Rocky Mountains , from southwest Alberta and southeastern British Columbia south through Colorado and New Mexico into the northern states of Mexico . It is also found through the Great Basin states of Nevada and Utah , in the eastern Sierra Nevada and White Mountains of Northern California , and in the San Bernardino and San Gabriel Mountains of

648-525: The seeds; the scales are not fragile. In whitebark pine, the cones are 4–7 cm ( 1 + 1 ⁄ 2 – 2 + 3 ⁄ 4  in) long, dark purple when immature, and do not open on drying, but are fragile and are pulled apart by birds to release the seeds. A useful clue is that whitebark pines almost never have intact old cones lying under them, whereas limber pines usually do. In the absence of cones, limber pine can also be hard to tell from Western white pine ( P. monticola ) where they occur together in

675-403: The trees. There is some evidence that P. flexilis has a symbiotic relationship with nitrogen-fixing bacteria that inhabit the needles. The species is generally shade tolerant and resistant to fire, but does not thrive in dense habitats, instead occurring in areas relatively hostile to other species. Limber pine is susceptible to white pine blister rust , caused by Cronartium ribicola ,

702-518: Was identified in 2006 near the Alta Ski Area in Utah; called "Twister", the tree was confirmed to be at least 1,700 years old and thought to be even older. Its pliant branches gives it the common name "limber" and specific epithet flexilis . Its needles are about 8 centimeters ( 3 + 1 ⁄ 4  in) long and a dark, blueish green. Its bark is heavily creased and dark grey. Its pale wood

729-411: Was retrieved by two researchers who counted 400 rings. Extrapolating this data gives an age close to 3,000 years. Pinus flexilis is a member of the white pine group, Pinus subgenus Strobus , and like all members of that group, the leaves ('needles') are in fascicles (bundles) of five, with a deciduous sheath. This distinguishes it from the lodgepole pine , with two needles per fascicle, and

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