SURVEY FOR DALEA CYLINDRICEPS (SANDSAGE -CLOVER) IN THE SANDSAGE PRAIRIE REGION OF SOUTHWESTERN

A report prepared for the Nebraska Game and Parks Commission

James H. Locklear Lauritzen Gardens January 12, 2015

SUMMARY

Dalea cylindriceps (sandsage prairie-clover) is a perennial herb native to the western . It is recognized as a of conservation concern in all but two of the eight states in which it has been documented and is recognized as a Tier I At-risk Species by the Nebraska Natural Legacy Project. Dalea cylindriceps is associated with sandsage prairie throughout most of its range in the Great Plains. In Nebraska, the most extensive occurrences of this community are located in southwest part of the state in Chase, Dundy, and Perkins counties. This study was undertaken to locate and document extant occurrences of D. cylindriceps in the sandsage prairie region of Nebraska. Despite four days of searching, no occurrences of D. cylindriceps were found in this region in 2014. Outside of the study area, two large and previously-unknown Nebraska occurrences of D. cylindriceps were located in Garden and Keith counties in 2014.

INTRODUCTION

Purpose of project

Dalea cylindriceps (sandsage prairie-clover) is a perennial herb native to the western Great Plains. Occurrences are known from , , Nebraska, , Oklahoma, , , and . Despite the large extent of its historical distribution, D. cylindriceps has been collected infrequently and occurrences are scattered and local (Locklear 2013b). As noted in Flora of Nebraska (Kaul et al. 2011), “This distinctive species is rare almost throughout its wide geographic range.” Dalea cylindriceps is tracked as a species of conservation concern in all but two of the states in which it has been documented, and is ranked G3G4 by NatureServe and as a Tier I At-risk Species by the Nebraska Natural Legacy Project.

Dalea cylindriceps has a strong affinity for sandsage prairie and most occurrences outside of Nebraska are associated with this plant community (Locklear 2013b). There are extensive tracts of sandsage prairie in southwestern Nebraska (Farrar 1993a, 1993b; Kaul & Rolfsmeier 1993; Rolfsmeier & Steinauer 2010) which would appear to provide potential habitat for D. cylindriceps, suggesting the value of more intensive survey for this species in the region. The purpose of the project was to locate and document extant occurrences of D. cylindriceps in the sandsage prairie region of southwestern Nebraska.

Plan of work

The 2014 study entailed search of sandsage prairie occurrences in Chase, Dundy, and Perkins counties in southwestern Nebraska for populations of Dalea cylindriceps. The field work took place over four days, August 11-14, 2014, and was timed to coincide with the peak flowering period of the species. The search for historical occurrences was guided by locality data derived 1 from herbarium specimens held by the Bessey Herbarium of the University of the Nebraska State Museum. Search for previously unrecorded occurrences was facilitated by locating potential habitat with the aid of topographic and county soil survey maps and attempting to reach this habitat via county roads. It was also guided by locality data derived from herbarium specimens of cycloides and Penstemon ambiguus, two species that only occur in Nebraska in association with sandsage prairie.

Previous Investigations

I carried out a conservation assessment of Dalea cylindriceps for the NNLP in 2013 in which I surveyed 22 sites in Nebraska where this species has been observed or collected in the past (Locklear 2013a). The survey included three historical occurrences from Dundy County, but no D. cylindriceps were observed at these sites in 2013. Five small, extant occurrences were located during the survey in four northwest Nebraska counties (Box Butte, Morrill, Sheridan, and Sioux counties). Based on this survey, it appears D. cylindriceps has undergone significant population decline in Nebraska, although extensive areas of potential habitat remain to be searched for this species.

Species Information

Detailed species information for Dalea cylindriceps including nomenclature, history, description, distribution, and ecology are included in recent publications by Locklear (2013a, 2013b) and will not be repeated here.

Study Area

This survey targeted occurrences of sandsage prairie in southwestern Nebraska (Chase, Dundy, and Perkins counties). This study area is located in the northern portion of the High Plains section of the Great Plains Physiographic Province (Fenneman 1931). The surface geology of the region is influenced by Tertiary-age non-marine deposits of the Ogallala Group (Miocene to earliest Pliocene). Windblown sand and/or loess mantle the Ogallala bedrock throughout most of the study area except where it is exposed along river valleys. The study area is located in the watershed of the Republican River.

Sandsage prairie is associated with two geographically distinct dune fields within the study area—the Wray Dune Field and the Imperial Dune Fields (Muhs & Holliday 1995). The Wray Dune Field is the larger and extends from Yuma and Phillips counties in northeastern Colorado (covering 4680 km2) into southwestern Nebraska (covering more than 2000 km2) where it occupies much of the western half of Dundy County and extends into the southwest portion of Chase County (Madole 1995). The sands of the Wray Dune Field were derived from South Platte River sediments (Muhs et al. 1996). The Imperial Dune Fields are located to the north and east of the Wray Dune Field in Chase and Perkins counties, with an isolated field in Hayes County. The sands of the Imperial Dune Fields were derived from both the Nebraska Sandhills (quartz-rich) and the South Platte River dune fields (K-feldspar rich) of northeastern Colorado (Muhs et al. 2000).

The topography of these dune fields varies from low, rolling hills with relatively flat crests to more choppy sandhills with steep sides and local relief from a few meters to as much as 60 m (200 ft). Soils formed in this eolian sand are deep, excessively drained, and very rapidly permeable. The predominant soil association is Valent sand (Paden et al. 1982; Wilson et al. 2004).

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Sandsage prairie is a steppe community in which the sand sagebrush ( filifolia) is a dominant element. This community type is found in sandy habitat throughout a large area of the western Great Plains, from South Dakota and Wyoming south into Texas and New Mexico (Kuchler 1985). While A. filifolia is a constant in this community type, the co-dominant graminoids vary depending on topoedaphic factors, with typical associates including sand bluestem (), prairie sandreed ( longifolia), little bluestem (), and sand dropseed (). Likewise, the forb component is influenced locally by topoedaphic factors and varies along a north-to-south gradient, with higher species diversity found in occurrences in the southwestern Great Plains.

The sandsage prairie region of southwestern Nebraska shares many plant species with the Nebraska Sandhills to the north, but a few arenaceous species are limited to this part of the state, notably , Linum berlandieri, Penstemon ambiguus, Pomaria jamesii, and Ratibida tagetes (Kaul et al. 2011; Rolfsmeier & Steinauer 2010). These species are more common in the southern Great Plains and reach the northern limits of their distributions in southwestern Nebraska.

Jon Farrar (1993a, 1993b) authored two excellent articles on the history, ecology, and conservation challenges of sandsage prairie in Nebraska for NEBRASKAland magazine.

RESULTS

Survey of historical occurrences of Dalea cylindriceps in southwestern Nebraska – Three historical occurrences of Dalea cylindriceps are known from the sandsage prairie region of southwestern Nebraska, all from Dundy County. Information for these is summarized below. Search was made of these sites in 2013 and 2014 but no D. cylindriceps plants were observed. Locality data for these occurrences are presented in Appendix A.

Benkelman 1916

Initial record: J.H. Bates s.n. (NEB); 28 July 1916 General location: In the vicinity of Benkelman Survey dates: 23 July 2013; 11 August 2014

Haigler 1996

Initial record: S. Rolfsmeier 12963 (NEB); 10 September 1996 General location: Sandhills north of Haigler; Locklear searched this site in 2010 and found no D. cylindriceps but did locate a small population ca. 1.5 mile west and 1.5 south of this site (see Haigler 2010) Survey dates: 05 July 2010; 23 July 2013; 12 August 2014

Haigler 2010

Initial record: Small population (2 individuals counted) observed by Locklear on 05 July 2010 General location: Sandhills north of Haigler Survey dates: 23 July 2013; 12 August 2014

General survey of sandsage prairie in southwestern Nebraska – I searched approximately 25 occurrences of sandsage prairie in Dundy, Chase, and Perkins counties but found no occurrences

3 of Dalea cylindriceps. Many stands of sandsage prairie in the region appeared to be in relatively good condition but a more systematic and thorough assessment of species diversity at these sites would be needed to determine the true ecological condition of these occurrences. Some occurrences with disturbed areas were being invaded by the exotic weed kochia (Kochia scoparia), particularly sites adjacent to cultivated cropland.

The primary graminoid co-dominant associates of in the sandsage prairie communities of southwestern Nebraska are sand bluestem, prairie sandreed, needle-and-thread (Hesperostipa comata), little bluestem, and blue grama ( gracilis). Sand bluestem and sand muhly (Muhlenbergia pungens) become more prominent on the slopes and crests of steeper dunes where there is more exposed sand while needle-and-thread is more prevalent in occurrences on relatively level terrain. Yucca (Yucca glauca) is often present. Commonly associated forbs include Ambrosia psilostachya, Asclepias arenaria, Croton texensis, Erigeron bellidiastrum, Eriogonum annuum, Helianthus petiolaris, Mentzelia nuda, and Mirabilis glabra. Less frequently encountered forbs include Dalea villosa, Ipomopsis longifolia, Palafoxia sphacelata, Phlox andicola, and Tradescantia occidentalis.

During the survey, I came across plants that appeared to be Chenopodium cycloides at two sites in Dundy County, one south of Benkelman and one north of Haigler. Chenopodium cycloides is a sandsage prairie specialist that is ranked G3G4 by NatureServe and has been designated a Tier I At-risk species (S1) by the NNLP. were collected from these plants and have been submitted to other authorities to determine the identity. NNHP rare plant survey forms will be submitted if these plants are determined to be C. cycloides.

Occurrences of Dalea cylindriceps located outside of study area – Two previously undocumented occurrences of Dalea cylindriceps were located in Garden and Keith counties in 2014. Information is provided below. Locality data for these occurrences are presented in Appendix A.

The Eagle Canyon Road occurrence was notable for several reasons. First, it contains the largest Dalea cylindriceps population discovered so far in Nebraska. Second, D. cylindriceps was the most abundant forb in the community. Third, the plants in the occurrence appeared to be of fairly uniform age, the majority being large, robust, multi-stemmed individuals with multiple inflorescences, giving the impression that the population was the result of a synchronized germination event. Finally, it was associated with Western Sand Prairie rather than Sandsage Prairie.

Eagle Canyon Road

Keith County General location: South side of Lake McConaughy Survey date: 31 July 2014 Estimated number of individuals: 300-500 Soil type: Sarben Loamy Fine Sand Plant community type: Western Sand Prairie dominated by Schizachyrium scoparium, Sporobolus cryptandrus, and Bouteloua curtipendula.

Lisco Bridge

Garden County General location: South side of North Platte River near Lisco

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Survey date: 31 July 2014 Estimated number of individuals: 50-75 Soil type: Valent Fine Sand Plant community type: Sandsage Prairie dominated by Artemisia filifolia in association with Andropogon hallii and .

LITERATURE CITED

Farrar, J. 1993a. Sandsage prairie: a history of the land. NEBRASKAland 71(7):22–29. Farrar, J. 1993b. Sandsage prairie: the Cinderella sandhills. NEBRASKAland 71(7):30–41. Fenneman, N. M. 1931. Physiography of the Western United States. McGraw-Hill Book Company, New York. Kaul, R. B. and S. B. Rolfsmeier. 1993. Native vegetation of Nebraska. Map, 1: 1,000,000, 16 colors. Conservation and Survey Division, University of Nebraska-Lincoln. Kaul, R. B, D. Sutherland, and S. Rolfsmeier. 2011. The flora of Nebraska, 2nd ed. School of Natural Resources, University of Nebraska-Lincoln, Lincoln, Nebraska. Kuchler, A. W. 1964 (1985). Potential Natural Vegetation of the Conterminous United States. American Geographic Society Special Publication No. 36 (1964) and U. S. Geological Survey, Reston, Virginia (1985). Locklear, J. H. 2013a. Dalea cylindriceps Barneby (sandsage prairie-clover): a survey of historical occurrences in Nebraska. Unpublished report prepared for the Nebraska Natural Heritage Program, Nebraska Game and Parks Commission by Lauritzen Gardens, Omaha, Nebraska. Available: http://outdoornebraska.ne.gov/wildlife/programs/legacy/pdfs/project- files/Dalea2013ReportForWeb.pdf. Locklear, J. H. 2013b. Taxonomic identity and historical accounts of Dalea cylindriceps (Fabaceae), a species of conservation concern in the Great Plains (U.S.A.). J. Bot. Res. Inst. Texas 7(2): 879 – 890. Madole, R. F. 1995. Spatial and temporal patterns in late Quaternary eolian deposition, eastern Colorado, U.S.A. Quaternary Science Reviews 14: 155-177. Muhs, D. R. and V. T. Holliday. 1995. Evidence of active dune sand on the Great Plains in the 19th century from accounts of early explorers. Quaternary Research 43: 198 – 208. Muhs, D. R., T. W. Stafford, Jr., S. D. Cowherd, S. A. Mahan, R. Kihl, P. B. Maat, C. A. Bush, and J. Nehring. 1996. Origin of the late Quaternary dune fields of northeastern Colorado. Geomorphology 17: 129-149. Muhs, D. R., J. B. Swinehart, D.B. Loope, J. Been, S.A. Mahan, and C.A. Bush. 2000. Geochemical evidence for an eolian sand dam across the North and South Platte rivers in Nebraska. Quaternary Research 53: 214 – 222. Paden, H., D. Loges, and R. Stapes. 1982. Soil Survey of Chase County, Nebraska. United States Department of Agriculture, Soil Conservation Service, in cooperation with Conservation, University of Nebraska. Rolfsmeier, S. B. and G. Steinauer. 2010. Terrestrial ecological systems and natural communities of Nebraska; Nebraska Natural Heritage Program, Nebraska Game and Parks Commission, Lincoln, Nebraska. Schneider, R., M. Humpert, K. Stoner, and G. Steinauer. 2005. The Nebraska Natural Legacy Project: A Comprehensive Wildlife Conservation Strategy. Nebraska Game and Parks Commission, Lincoln, Nebraska. Wilson, J. R., A. J. Stuebe, and P. D. Young. 2004. Soil Survey of Dundy County, Nebraska. United States Department of Agriculture, Natural Resources Conservation Service, in cooperation with the University of Nebraska, Conservation and Survey Division, and the Upper Republican Natural Resources District.

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