1997 Results - Erosion Utah
1997 Results - Erosion
Sheet and rill erosion have had varying
effects on cultivated and noncultivated cropland in Utah. In cultivated areas
the erosion rate for the monitoring period between 1982 and 1997 varied from 1.4
to 1.6 tons per acre per year. On noncultivated cropland, it averaged about .2
tons. The totals equate to about .8 ton erosion from water. The erosion from
water on pastureland has been about .1 to .2 tons per acre.
The Conservation Reserve Program has helped a great deal
in Utah. The first recordings for erosion on any CRP land were in 1987. The
initial readings indicate that water erosion was occurring at a rate of about
3.2 tons per acre in Utah. By 1997, the data indicated that erosion rates were
down to about 0.9 tons, a reduction of about 72 percent. Prior to the CRP
program, these were the most erosive soils in the state.
Wind erosion was monitored separately for the same 15-year
period. Cultivated cropland was being blown away at a rate of 6.0 to 6.7 tons
per acre until 1997 at which time it was slowed to about 4.5 tons per acre. The
noncultivated rates ranged from 1.1 to 2.1 until 1997 when it dropped to 0.7.
The average for Utah cropland by 1997 had dropped from 4.4 to 2.3. The most
dramatic drop was again, in CRP areas. The 1997 figures were almost 1 tenth of
what they were just ten years previously. Overall decreases on pastureland were
about .2 tons. In 1982 they were about 1.5 and in 1997, about 1.3 with increases
and decreases throughout the 15-year monitoring period.
occupies a very small part of the total surface area of the state. It comprises
about 3% of the total surface area as of 1997. In 1982 that figure was closer to
4%. The database for 1997 indicated that about 705,300 acres were cultivated
and 973,800 were noncultivated. The difference being that cultivated ground is
in row crops or hay and pasture in rotation with row crops. Non cultivated
ground is that which is in permanent hay, pasture or orchards. It is interesting
to note that according to NRI data, there was about 105,000 acres of cropland
converted to urban land throughout the state during the 15-year period between
1982 and 1997.
Much of the cropland is non-irrigated. In these cases, the
average annual precipitation is more than 12 inches and the frost-free season is
more than 60 days. The soils are loamy with about 3.5 inches of available water
holding capacity. The better sites have few if any rocks but, many of these
areas are very gravelly or cobbly. Non-irrigated cropping is normally on valley
side slopes of 25 percent or less and low lying basins. Areas suitable for this
type of farming normally have a range of mountains nearby which assist with the
proper distribution of precipitation. Since most of the rain falls in the
mountainous areas, the soils near the mountains receive more water than those
more distant from the mountains.
Irrigated farming is normally in valleys that have
affordable water, loamy soils and a growing season of 50 days or more. Other
factors include slopes of less than 20 percent and soils with an available water
holding capacity of about 4 inches in the upper 3 feet.
Cropping of both types are divided into field and orchard
crops. Dominant field crops are spring and winter wheat, barley, beans, corn for
grain and silage, alfalfa and grass hay, oats, onions and potatoes.
Non-irrigated acreages are normally in fall or spring wheat or barley. Dominant
orchard crops include apples, apricots, cherries, peaches, and pears.
Orchards of apples, cherries, peaches, pears and apricots
are found in several locations around the state. Fruit and vegetable crops make
up about 5 percent of Utah's crops. Many of the Utah agricultural products are
being used in other states and in other countries.
Prime farmland is described as farmland with resources
available to sustain high levels of production. The exact definition is listed
in the National Soil Survey Handbook. In Utah, it normally requires irrigation
to make prime farmland. In general, prime farmland has a dependable water
supply, a favorable temperature and growing season, acceptable levels of acidity
or alkalinity, an acceptable content of salt and sodium, and few or no rocks.
Unique farmland in Utah is primarily in the form of orchards. Farmlands of
statewide importance are those soils which nearly qualify for prime farmland and
produce high sustainable yields.