2011-11-02_REVISION - M2003019 (5)

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JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC 0 0 5 10 22 35 15 10 3 0 0 0 Site Type: Rangeland MLRA: 69 - Upper Arkansas Valley Rolling Plains Gravel Breaks R069XY064C0 • Prescribed grazing that allows for adequate recovery opportunity following each grazing event and proper stocking will maintain the Sideoats Grama, Little Bluestem, Blue Grama Plant Community (HCPC). Increased Blue Grama with Decreased Mid and Tall Grass Plant Community This plant community developed with continuous grazing without adequate recovery periods during the growing season. The dominant grass is blue grama. Little bluestem and sideoats grama are still present as secondary grasses in the community. Big bluestem, Indiangrass, switchgrass, prairie sandreed, needleandthread, western wheatgrass, purple prairie clover and winterfat have been significantly reduced. Hairy grama, sand dropseed, red threeawn as well as Hoods phlox, hairy goldaster, western ragweed and slimflower scurfpea have increased. Woody plants include small soapweed and skunkbush sumac. Plant frequency and vigor have decreased. Reduction of tall, mid and rhizomatous grasses, nitrogen - fixing forbs, shrub component and increased warm season short grass has begun to alter the biotic integrity of this community. Water and nutrient cycles are becoming impaired. Litter levels have been reduced. Flow paths and rills are more apparent. Pedestalled plants are common. Desertification is in an early stage. Total annual production, during an average year, ranges from 200 to 700 pounds of air -dry weight and will average 400 pounds. The following is the growth curve of this plant community expected during a normal year: Growth curve number: C06905 Growth curve name: Warm season dominant, cool season sub - dominant; MLRA -69; upland coarse textured soils. y percen o '' o a ' annual gro Transitions or pathways leading to other plant communities are as follows: • Continuous grazing without adequate recovery opportunities between grazing events will shift this plant community across an ecological threshold toward the Blue Grama Sod, Threadleaf Sedge Plant Community. Weedy species are starting to invade and almost all mid grasses are removed. • Prescribed grazing which allows for adequate recovery periods following each grazing event and proper stocking will move this plant community toward the Little Bluestem, Sideoats Grama, Plant Community (HCPC). • Long-term non -use (rest) and no fire will shift this plant community toward the Bare Ground, Annuals, Cryptogams Plant Community. This transition may take 40 years or more to achieve. Blue Grama Sod Plant Community This plant community developed with continued grazing without adequate recovery periods between grazing events. Blue grama dominates the community and exhibits a mosaic sodbound appearance. Tall grasses have been removed. Little bluestem and sideoats grama may remain in remnant amounts on steeper slopes. Forbs and shrubs that have increased are wormwood, western ragweed, rush skeletonplant, hairy goldaster, fringed sagebrush, small soapweed and broom snakeweed. Cushion plants such as mat loco, Hood's phlox and sessile nailwort have increased. Species diversity and production have been severely reduced. Litter levels are very low. Mineral and water cycles are impaired due to the loss of deeper- rooted grasses, forbs and shrubs. Rills are evident and soil loss is obvious, especially on steeper slopes. Pedestalled plants with exposed roots are common. Desertification is advanced. Technical Guide Section IIE 7 USDA NRCS Rev. 3/04