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Contents : ATTACHMENT SS2 REGION 2 SENSITIVE SPECIES EVALUATION FORM Species: Aristida havardii Vasey Havard s threeawn SYNONYMS: A. barbata E. Fourn. Great Plains Flora Association 1977 Sutherland 1991 included in A. purpurea Nutt. in Weber & Wittman 2001 Criteria 1 Distribution within R2 2 Distribution outside R2 Rank A Rationale Known from only a few populations from se-most (Baca Co) and sw-most (Morton Co) KS. Vouchers at KANU from Baca Co CO and Morton Co KS. Species reaches the ne-most limit of its range in R2. Status: G5 KS S1. Confidence in Rank High or se-most CO and sw-most KS s through w TX and into central Mexico thence n into s 2/3 of NM and AZ. Reported by Correll & Johnston to be rare in the w Plains Country of TX but abundant in Trans-Pecos TX. C Confidence in Rank High or 3 Dispersal Capability 4 Abundance in R2 5 Population Trend in R2 Medium or Low D/B Medium or Low Evaluator was unable to find any direct information about species dispersal capability rank D . Species is likely wind dispersed however and apparently occupies a wide variety of habitats within shortgrass prairies rank B . Confidence in Rank High or Medium or Low Limited to a few populations in Cimmarron River drainage in Baco Co CO and Morton Co KS in the smost part of R2. See comments about possibility of local extinction in sections 6 and 7. A D Confidence in Rank High or Medium or Low Species is known in the Cimarron NG from a single population of ca 150 200 plants along a cattle-grazed eroding bank of the Cimarron River (Freeman 1989). Freeman (2001) notes that population has not been resurveyed since 1988. Species is known from older collections made within or very near boundaries of Comanche NG in Baca Co CO (recorded as common on herbarium specimen label of S. Stephens 42555 & R. Brooks). Confidence in Rank High or Medium or Low USDA-Forest Service R2 Sensitive Species Evaluation Form Literature Citations Anderson 1950 Freeman 1989 Freeman 2001 Freeman in prep. Great Plains Flora Association 1977 Rubright 2000 Sutherland 1991 Weber & Wittman 2001 Correll & Johnston 1979 Freeman 1989 Freeman 2001 Freeman in prep. Freeman in prep. Martin & Hutchins 1980 Sutherland 1991 Weber & Wittman 2001 Freeman 1989 Sutherland 1991 Freeman 1989 Freeman 2001 Sutherland 1991 Freeman 1989 Freeman 2001 Page 1 of 3 ATTACHMENT SS2 Species: Aristida havardii Vasey Havard s threeawn SYNONYMS: A. barbata E. Fourn. Great Plains Flora Association 1977 Sutherland 1991 included in A. purpurea Nutt. in Weber & Wittman 2001 Criteria 6 Habitat Trend in R2 Rank A 7 Habitat Vulnerability or Modification 8 Life History and Demographics B B Rationale Species reported by Freeman (1989) to occupy open dry sandy to gravelly slopes and uplands in shortgrass prairie often in disturbed sites. Species reaches the ne-most limit of its distribution in R2 where it is presumably already limited by scarcity of appropriate habitat. Freeman (1989) noted that known population in Cimarron NG was threatened by disturbance from livestock grazing and erosion of substrate by Cimarron River. Noting that livestock grazing had accelerated erosion Freeman (1989) recommended restricting or eliminating livestock grazing from area of known occurrence. As noted in section 5 however the population has not been surveyed since 1988 (Freeman 2001). Confidence in Rank High or Medium or Low Species is reported by Freeman to occupy open dry sandy to gravelly slopes and uplands in shortgrass prairie often in disturbed sites. Freeman noted that population in Cimarron NG was threatened by disturbance from livestock grazing and bank erosion by Cimarron River. Noting that livestock grazing had accelerated erosion that author recommended restricting or eliminating livestock grazing from area of known occurrence. Evaluator was unable to find information on habitat in Baco Co CO. Confidence in Rank High or Medium or Low Perennial grass. Flowering and fruiting July through October. Evaluator was able to find little information on life history. However species is both palatble to cattle and known to occupy fragile habitat where it occurs in the Cimarron NG. Consequently species may face local extirpation from grazing or trampling by livestock. Further studies are warranted. Confidence in Rank High or Literature Citations Freeman 1989 Freeman 2001 Freeman 1989 Freeman 1989 Sutherland 1991 Medium or Low Evaluator: Caleb A. Morse R.L. McGregor Herbarium (KANU) University of Kansas Campus West 2045 Constant Ave Lawrence KS 66047 Date: 12/29/01 National Forests in the Rocky Mountain Region where species is KNOWN (K) or LIKELY (L)1 to occur: 1 Likely is defined as more likely to occur than not occur on the National Forest or Grassland. This generally can be thought of as having a

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