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Drainage class Well drained EXHIBIT J-1 <br /> Permeability class Moderate to moderately rapid <br /> Depth to restrictive layer 5-20 in <br /> Soil depth 5-20 in <br /> Surface fragment cover<=3" 11-49% <br /> Surface fragment cover>3" 0-13% <br /> Available water capacity 0.5-2 in <br /> (Depth not specified) <br /> Calcium carbonate equivalent 1-30% <br /> (Depth not specified) <br /> Electrical conductivity 0-2 mmhos/cm <br /> (Depth not specified) <br /> Sodium adsorption ratio 0-10 <br /> (Depth not specified) <br /> Soil reaction(1:1 water) 7.9-9 <br /> (Depth not specified) <br /> Subsurface fragment volume<=3" 0-45% <br /> (Depth not specified) <br /> Subsurface fragment volume>3" 0-11% <br /> (Depth not specified) <br /> Ecological dynamics <br /> Ecological Dynamics of the Site <br /> As ecological condition deteriorates due to anthropogenic disturbances and/or the alteration of the natural <br /> disturbance regime, native perennial bunch grasses decrease while pinyon and juniper increase.When the potential <br /> natural plant community is burned and/or drought conditions persist, pinyon and juniper decrease while native <br /> perennial bunch grasses increase. <br /> State 1: Reference State <br /> This state represents the natural variability and dynamics of this site that occurred naturally.This state includes the <br /> dominant biotic communities that would have occurred on this ecological site prior to European Settlement. The <br /> dominant aspect of this site is Pinyon and Utah Juniper with an understory of shrubs and associated grasses. <br /> Fluctuations in species compositions and relative production may change from year to year dependent upon <br /> abnormal precipitation or other climatic factors.The primary disturbance mechanisms for this site in reference <br /> condition include drought, insects, and infrequent fire. Because catastrophic disturbances like a crown fire or <br /> drought happen with long intervals,these communities have long periods of succession, (i.e. long periods of dense <br /> Pinyon and Juniper)-300-600 years in upland/foothills ecological site zone and 300 to 1,000 in semi-desert <br /> ecological site zone.Typically,fires occurred in late spring through mid-summer following several wet years that <br /> allowed the fine fuels to become more contiguous.The higher in elevation and higher precipitation area would bum <br /> more frequently as they would have more fine fuels in the understory.The timing of drought, and fire, coupled with <br /> surface disturbance can dictate whether the community can stay within the reference state or if the community <br /> transitions into another state. <br /> When this site is at or near it's potential, pinyon pine and Utah juniper dominate the site and make up over 80 <br /> percent of the plant community. Understory production is very limited and provides marginal amounts of forage for <br /> livestock and or wildlife. It does provide good escape cover and thermal cover for deer.When the tree canopy cover <br /> exceeds 30 percent, diversity, both plant and animal drops to its lowest level. <br /> Community Phase 1.1: Pinyon-Juniper Woodland <br /> A well-developed understory with a canopy of younger pinyon and Utah juniper. At this stage Utah juniper may be <br /> dominant over pinyon. Pinyon trees are more susceptible to drought, insects, and disease than Utah juniper trees. <br /> In fact, it is difficult to identify methods beside fire that naturally reduce Utah juniper.After long periods of drought <br />