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eschutes County contains extreme variations in geology, climate and vegetation, and as a result, the soils throughout the county are diverse. Testing of soils is essential. When working with the soil on your property, a soil test is used for determining fertility and better understanding soil properties.

Deschutes County Soil Basics

Geology plays a large role in determining soil properties. In Deschutes County, geology includes basalt bedrock, pumice rock, volcanic ash, glacial deposits and materials deposited by water. The majority of soils occur over basalt bedrock with a mantle of sandy pumice volcanic ash. Due to the volcanic ash, the local soils tend to be fragile and are susceptible to wind and water erosion when not adequately protected. Soils are composed of clay, silt and sand. The combination of these materials determines the texture of your soil. For example, a soil with equal amounts of clay, silt and sand has a loamy texture. Sandy textures can’t hold much water, and clay textures slow down water movement through soil. If irrigating, it is important to know your soil texture. Textures of the soils on your property and hundreds of other soil properties and land use interpretations are available to the public in a document called Soil Survey. Using the soil survey is essential in managing your land.

Soil Testing

Soil testing is a good way to determine the nutrient level of your soils, as well as their acidity and alkalinity. Common nutrient deficiencies in our area include nitrogen (N), phosphorus (P), potassium (K) and sulfur (S). The OSU Extension Service office can provide a list of soil-testing labs. When results are returned, Extension Service staff can help you interpret the results. Several agricultural supply stores in Central Oregon can also help you get soil samples processed and will explain results to you.

Soil Survey

A soil survey exists for almost all privately owned land in Deschutes County. Soil surveys are available from Web Soil Survey (http://websoilsurvey.nrcs.usda. gov). If you have questions about using the Web site or the information, contact the Natural Resources Conservation Service.

Consulting your soils survey is a great place to start when you want to know the general properties of the soils comprising your land.


Deschutes County Rural Living Handbook

Deschutes rlh 2010