Soil Properties and Their Influence on Windbreak and Environmental Plantings Continuation

 

Windbreak suitability group 3 – Loamy Soils (8%)*

*Loam is an ideal mix of silt, sand, clay, and organic matter

The soils in this group are very deep or deep and moderately-well to well drained.  They have loamy surface and subsoil layers and have less than 35% rock fragments by volume throughout.  Available water capacity of the soil is very good.  In the upper 12 inches of the soil the pH is less than 7.9, the electrical conductivity is less than 2 mmho/cm (not too salty) and the carbonates are generally absent, but never exceed 5% calcium carbonate equivalent.  Depth to a water table during the growing season is more than 5 feet and bedrock is not an issue.

This group is well suited for windbreaks and environmental plantings.

 

Windbreak suitability group 5 – Droughty Soils (9%)

The soils in this group are very deep or deep and moderately-well drained to well drained.  They have loamy surface and subsoil layers.  Rock fragments throughout the soil may range to 60% by volume.  Available water capacity of the soil ranges is moderate.  In the upper 12 inches of soil the pH ranges from 7.9 to 8.4 (plants tend to prefer pH 7 or lower), the electrical conductivity is less than 4 mmho/cm (more salty), and calcium carbonate equivalent ranges from 5 to 15%.  Depth to a water table during the growing season is more than 5 feet and bedrock is not an issue.

This group is moderately suited for windbreaks and environmental plantings.  The amount of carbonates, high pH, and droughtiness of the soil moderately limit the selection of trees and shrubs.

 

Windbreak suitability group 6 – Excessively drained Soils (30%)

The soils in this group are moderately deep overlying sand, gravel, or similar layers with a permeability of more than 20 inches/hour (highly permeable) or other layers restrictive to roots.  These soils are well drained to excessively drained.  The upper parts of the soils are loamy, and may contain up to 60% rock fragments by volume.  Available water capacity of the soil to underlying bedrock or other restrictive layers is relatively low.  In the upper 12 inches of soil, the pH is less than 7.9, the electrical conductivity is less than 2 mmho/cm, and the calcium carbonate equivalent is less than 5 percent.  Depth to a water table during the growing season is more than 5 feet.

This group is poorly suited for windbreaks and environmental plantings.  The droughtiness of the soil significantly limits the selection and rate of growth of trees and shrubs.  Providing permanent supplemental water is recommended for successful establishment and growth of the trees and shrubs.

 

Windbreak suitability group 10 – On Site Evaluation (34%)

The soils of this group have one or more characteristics that are severely limiting to the planting and growth of trees and shrubs.  Among these characteristics are: the soil depth is shallow; available water capacity of the soil is very low or there is a short distance to underlying bedrock or other restrictive layers; the calcium carbonate equivalent is more than 40 percent or the electrical conductivity is more than 16 mmho/cm (very salty) in the upper 12 inches of the soil; or a water table during the growing season is within 18 inches of the soil surface (very shallow).

This group is not usually recommended for windbreaks and environmental plantings.  However, on site investigations may reveal that some tree and shrub planting can be made with special treatments.  The selection of species must be tailored to the soil conditions at the site.

When it comes to selecting trees and shrubs for a windbreak or environmental planting it is important to review the soil survey for the site in which the trees and shrubs are to be planted.  Remember this is just a starting point.  To truly understand the soils at the site it is best to have soil samples from the site analysis at a soils lab.  Once the soils on site have been analysis tree and shrub selection can begin.

             Individuals can do their own soil investigations by using the UDSA/NRCS Web Soil Survey at www. websoilsurvey.nrcs.usda.gov or call, email, or stop by if you would like help in gathering soil information for your property.

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