Laserfiche WebLink
ROfi78YO24CO—Sandy Plans EcologMal Site--[Ibort County,Colorado,Eastern Part <br /> Recurrent drought has historically impacted the vegetation of this region. <br /> Changes in species composition will vary depending upon the duration and <br /> seventy of the drought cycle,and prior grazing management_Recent drought <br /> events(since 2002)have increased mortality of blue grama and other <br /> bunchgrasses significantly in some locales. <br /> This site developed with occasional fires being part of the ecological processes <br /> Historic fire frequency(pre-industrial),is estimated at 10-14 years(Guyette <br /> 2012),randomly distributed,and started by lightning at various times throughout <br /> the growing season. Early human inhabitants were also likely to start fires for <br /> various reasons(deliberate or accidental).It is believed that fires were set as a <br /> management tool for attracting herds of large migratory herbivores(Stewart. <br /> 2002).The impact of fire over the past 100 years has be relatively insignificant <br /> due to the human control of wildfires and the lack of acceptance of prescribed fire <br /> as a management tool. <br /> Grazing by large herbivores,without adequate recovery penoris following each <br /> grazing occurrence,will cause blue grams to increase Blue grana may <br /> eventually form a sod-like appearance.Prairie sandreed,sand bluestem,and <br /> switchgrass will decrease.Prairie sandreed may persist in remnant amounts <br /> protected by remaining shrubs. Cool season grasses such as needleandthread <br /> and western wfleatgrass will decrease in frequency and production.Key shrubs <br /> such as western sand cherry and fourwing saitbush will decrease in frequency <br /> and production.American vetch and other highly palatable fortis will also <br /> decrease.Fender threeawn,annuals and bare ground increases under heavy <br /> continuous grazing,excessive defoliation,or long-term non-use. Much of this <br /> ecological site has been tilled and used for crop production.Other areas of this <br /> ecological site have been converted to suburban residence and small acreages. <br /> especially near the larger communities, <br /> The following is a diagram illustrates the common plant communities that can <br /> occur on the Sandy Plains site and the community pathways(CP)among plant <br /> communities.Plant Communities are identified by 1.1,1.2 etc.and are described <br /> In the narrative.Bold lines surrounding each state represent eoological <br /> thresholds.Transitions(T)indicate the transition across an ecological threshold <br /> to another state.Once a threshold has been crossed into another state,it may <br /> not be feasible to return to the original state,even with significant management <br /> inputs and practices.The ecological processes plant communities,community <br /> pathways,transition andfor restoration pathways will be discussed in more detail <br /> in the plant community descriptions following the diagram. <br /> Natural Resources web&ori Survey 10/23/2017 <br /> ++m Conservation Service 4eeoriai Cooperage*Sol Survey Page 2 at 2 <br /> 71 <br />