Shallow (Sw) 10-14" p.z.

Mechanism

Prescribed grazing with favorable precipitation, fire if enough fuel.
This plant community (State 2) is resistant to change. Blue grama and clubmoss form a thick sod which provides a competitive advantage for limited precipitation. Although the sod appears to prevent seedling establishment of high-successional species, recent research indicates the absence of seedlings within a mat of clubmoss is due to an inadequate seed bank in the soil (Romo and Bai 2004). When clubmoss cover is more than 20-25%, succession is not expected to occur within a reasonable length of time. However, significant succession may occur if the top soil is intact and if clubmoss is no more than a minor component of the plant community. Succession would be favored by prescribed grazing, an extended period of favorable precipitation and the re-implementation of the natural fire regime. The potential for succession is depicted by the dashed line in the diagram.
Significant economic inputs and time are required to move this plant community toward a higher successional state (those communities found in State #1) when the plant community is dominated by clubmoss, or if the soil surface has been lost to erosion. Production on a Shallow 10-14” p.z. ecological site is 40-50% less than it is on ecological sites with soils > 20 inches deep (eg, Silty 10-14” p.z., Clayey 10-14” p.z., and Sandy 10-14” p.z.). The lower response potential from mechanical treatment has a proportionate effect on the potential economic benefits. Therefore, mechanical treatments and range seeding are not normally recommended on shallow sites. In comparison to “normal” sites, environmental risks (such as erosion) are greater while economic benefits are less.