1997 Results - Erosion Utah

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.

Utah cropland 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.