FLOOD07893

• County: Weld
• Basin: South Platte
• Title: Soil Survey of Weld County, Northern Part
• Date: 4/14/1999
• Prepared For: Weld County
• Prepared By: USDA Soil Conservation Service
• Floodplain - Doc Type: Data

2

climate

Prepared by tha National Climatic Center, Asheville, North Carolina.

The survey area generally is warm in summer and has
freqent hot days. In winter, periods of very cold weather
occur as a result of Arctic air moving in fwm the north or
northeast; however, milder periods occur when westerly
winds are warmed as they move downslope. Most
precipitation falls as rain during the warmer part of the
year and normally is heaviest late in spring and early in
summer. Winter snowstorms are frequent, but snow
cover commonly disappears during milder periods.
In winter, the average temperature is 29 degrees F
and the average daily minimum temperature is 14
degrees. The lowest temperature on record, which
occurred at Greeley on February 1, 1951, is -39 degree's.
In summer, the average temperature is 70 degrees and
the average daily maximum temperature is 87 degrees.
The.highest recorded temperature, which occurred at Ft.
Lupton on June 23, 1954, is 108 degrees.
The total annual precipitation is 12 inches. Of this, 9
inches, or 75 percent, usually falls in April through
September, which includes the growing season for most
crops. In 2 years out of 10, the rainfall in April through
September is less than 6.5 inches. The heaviest 1-day
rainfall during the period of record was 3.2 inches at
Greeley on June 8, 1974. Thunderstorms occur on about
41 days each year, and most occur in summer.
The average seasonal snowfall is 40 inches. The
greatest snow depth at anyone time during the period of
record was 30 inches. On an average of 18 days, at
least 1 inch of snow is on the ground. The number of
such days varies greatly from year to year.
The average relative humidity. in midafternoon is about
40 percent. Humidity is higher at night, and the average
at dawn is about 69 percent. The sun shines 71 percent
of the time possible in summer and 70 percent in winter.
The prevailing wind is from the south. Average
windspeed is highest, 10.4 miles per hour, in April.
In some years during winter. a blizzard with high winds
and drifting snow occurs in the survey area and snow
remains on the ground for many weeks. In some years
during summer, hailStorms cause severe damage to
crops in the area

Pawnee National Grassland

By Steward J. Adams, district ranger, Forest Service.

The Pawnee National Grassland (see map at the back
of this publication) is one of 19 national grasslands in
the westem United States. Most of the Pawnee National
Grassland is flat to rolling prairie grassland intermingled
with privately owned farmland and grassland.
The national grasslands were started as part of an
economic program. The land originally was settled by
stockmen whose ranches covered vast areas of the
plains. During the late 1800's. overgrazing and

Soil survey

competition for forage started to be a problem. The
homestead acts of the late 1800's and early 1900's
brought in more and more farmers, and by 1913 about
35 percent of the area had been converted to cropland.
The drought and depression of the 1930's caused a
decline in the number of small cultivated farms. Farmers
could no longer make a living from small holdings
managed for intensive cash crops. Many farmers left the
area. The Bankhead-JonesFarm Tenant Act, passed in
1937, was a repurchase law designed to aid the
resettlement of farmers, to convert submarginal cropland
back to grassland, to help s.tabilize the economy, and to
assist those who chose to stay.
The Soil Conservation Service administered the
purchase units as land utilization projects from 1938 to
1954. The land was then transferred to the Forest
Service. Studies of the land were made, and in 1960 the
areas of rangeland suitable for permanent retention were
designated as national grasslands. The grasslands
became a part of the national forest system. In 1961 the
grassland in the survey area was designated Pawnee
National Grassland.
Presently, about 10,000 cattle graze the public land of
the Pawnee National Grassland, which facilitates the
total management and enhances the economy of the
area. The Objective of management of national
grasslands is to develop and execute conservation and
utilization programs for all renewable resources .in
national grassland areas; this, to the extent feasible,
promotes the integration of the federally administered
land with the associated private and other public lands
into natural management units, which favors the
development of sound land conservation and utilization
practices. Cattle use the forage about 5 months out of
the year. .
The federal land is open to hunting that is subject to
state laws and regulations. Wildlife in this grassland area
includes antelope, a few deer, some coyotes, and
rabbits. A few prairie dog towns are scattered throughout
the area.
One of the main recreational uses of the area is bird
watching. The grassland supports large numbers of birds
of many species, especially during migrations. The area
is known internationally as an excellent study area for
birds of prey, and it has good breeding populations of
unique high plains species such as mountain plover,
burrowing owl, McCowan's longspur, and chestnut-
collared longspur. Hikers also use areas of the
grassland. although there are no special hikifl9 trails.
Crow Valley Park is one-fourth mile north of the town
of Briggsdale. The park is Iccated among shade trees
along Crow Creek. Picnic and camping areas are in the
park. The campground is closed in winter.
Additional information on the Pawnee National
Grassland can be obtained from the locai 'office of the
Forest Service.