Tree Cholla, Walking-Stick Cholla SYNONYMS: Cylindropuntia Imbricata (Haw.) F.M

ATTACHMENT SS2

REGION 2 SENSITIVE SPECIES EVALUATION FORM

Species: Opuntia imbricata (Haw.) DC. var. imbricata candelabra cactus, tree cholla, walking-stick cholla SYNONYMS: Cylindropuntia imbricata (Haw.) F.M. Kunth [Weber & Wittman 2001a, 2001b]; Opuntia arborescens Engelm.

Criteria Rank Rationale Literature Citations • Benson 1982 Known from Archuleta and LaPlata Cos and se ¼ of CO, and scattered throughout the w ½ of KS. Weber & • Clark 1996 Wittman (2001a) cite species as “common in the Arkansas Drainage from Colorado Springs to the OK • Freeman 1989 border.” Species is considered to be native to the Cimarron River and possibly Arkansas River drainages in • Freeman 2000 1 KS. Other KS populations are assumed to have resulted from recent introductions by livestock or • Freeman in prep. horticultural plantings (McGregor, Freeman 1989 and C.C. Freeman pers. comm.). [Vouchers at KANU from • Great Plains Flora Association 1977 Distribution B Baca, Kit Carson and Lincoln Cos, CO; and Clark, Ellsworth, Ford, Hamilton, Kiowa, Logan, Meade, Morton, within R2 • Kaul 1991 Norton, Seward, Sherman, and Stevens Cos, KS.] • McGregor 1977 Status: G5; KS S2. • Shaw 1989 Confidence in Rank High or Medium or Low • Weber & Wittman 2001a • Weber & Wittman 2001b • Benson 1982 Archuleta and LaPlata Cos and se ¼ of CO, and scattered throughout the w ½ of KS; s through the w ½ of • Correll & Johnston 1979 TX to central Mexico; thence n to se AZ and throughout NM (fide Benson) • Freeman 1989 2 • Freeman in prep. Distribution B • Kaul 1991 outside R2 • Martin & Hutchins 1980 Confidence in Rank High or Medium or Low • Weber & Wittman 2001a • Weber & Wittman 2001b Evaluator was unable to find any direct information on dispersal capability [rank D]. However, species appears able to colonize new habitat through disbursal of fruit and vegetative propagules. Species is 3 believed to have expanded its range into w KS via transport of cattle from the sw Great Plains. While there • Freeman 1989 • Kinraide 1978 Dispersal B is some evidence that species does better on clay soils in CO, species has been found a variety of

Capability substrates in KS and CO. Confidence in Rank High or Medium or Low Species occurs in small, discontinuously distributed populations. Most KS populations are considered to to have resulted from recent introductions by livestock or horticultural plantings (McGregor, Freeman 1989 and 4 C.C. Freeman, pers. comm.). These generally consist of a single plant and probably cannot be considered • Freeman 1989 Abundance in B reproducing populations. As reported by Freeman, the majority of populations considered native consist of • McGregor 1977 R2 very few individuals and may be declining [see sect 5]. Confidence in Rank High or Medium or Low Freeman noted that the majority of KS populations consist of only a few (< 6), widely scattered indivuals. In these populations, Freeman noted frequent “senescent or dead individuals and the absense of young plants 5 suggest some populations are declining.” However, more recent data on these populations is not available. • Freeman 1989 Population B Species is not monitored in CO and C.C. Freeman and the evaluator (pers. obss.) have noted that species Trend in R2 occurs in abundance along the Front Range, especially in grazed areas. Confidence in Rank High or Medium or Low

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Criteria Rank Rationale Literature Citations

C.C. Freeman and the evaluator (pers. obss.) have noted that species occurs in abundance along the Front 6 Range, especially in grazed areas. However, Kinraide found species’ occurrence is negatively corollated with several species indicative of range deterioration and overgrazing, a frequent threat to shortgrass • Kinraide 1978 Habitat Trend B prairies. Kinraide suggests that species may not warrant treatment as a pest species [rank is a qualified B]. in R2 Confidence in Rank High or Medium or Low Kinraide found species is most common on clay soils, but populations have been reported from a variety of 7 sites, including sandy to gravelly soils in shortgrass- and sandsage prairies, pastures, and river floodplains • Freeman 1989 Habitat (Freeman). Kinraide found species’ occurrence is negatively corollated with several species indicative of • Kinraide 1978 Vulnerability B range deterioration and overgrazing, a frequent threat to shortgrass prairies. Freeman (1989), however, or posited that “grazing is a threat only where it results in serious vegetation loss and subsequent soil erosion.” • Ostlie et al. 1997 Modification Confidence in Rank High or Medium or Low Long-lived, tree-like or shrubby cactus. Flowering mid June through July; fruiting late July, fruits persistent. Kinraide found that species’ native distribution is limited by annual precipitation (28–48 cm) and mean January temperatures (>1 deg C). In addition, in El Paso Co CO, species does best on clay soils and on 8 areas with a s aspect. Species was found to be self-incompatible by McFarland et al. Those authors • Freeman 1989 Life History B concluded that species is probably pollinated by several species of large bees, primarily species of Diadasia • Kinraide 1978 and (Anthophoridae) and Lithurge (Megachilidae). Species’ success within native range may ultimately depend • McFarland et al. 1989 Demographics on availability of habitat for pollinators. Confidence in Rank High or 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 50% chance or greater of appearing on NFS lands.

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South Dakota Colorado NF/NG Kansas NF/NG Nebraska NF/NG Wyoming NF/NG NF/NG Likely Likely Likely Likely Likely Known Known Known Known Known

Arapaho-Roosevelt Samuel Cimmaron NG X3 Black Hills NF Shoshone NF NF R.McKelvie NF White River NF Halsey NF Buffalo Gap NG Bighorn NF Routt NF Nebraska NF Ft. Pierre NG Black Hills NF Grand Mesa, Uncompahgre, Ogalala NG Medicine Bow NF Gunnison NF Thunder Basin San Juan NF X NG Rio Grande NF Pawnee NG Pike-San Isabel NF Comanche NG X2 2 KANU catalog # 259852: CO, Baca Co: 15 mi S, 4 mi W Pritchett, 5 Jun 1968, S. Stephens 21845 & R. Brooks 3 Voucher specimens cited in Freeman (1989).

REFERENCES

Benson, L.D. 1982. The Cacti of the United States and Canada. Stanford University Press. Stanford, California. ix + 1044 pp. Clark, D.A. 1996. A floristic survey of the Mesa de Maya Region, Las Animas county, Colorado. Nat. Hist. Invent. Colorado 17: 1–44. Correll, D.S. and M.C. Johnston. 1979. Manual of the Vascular Plants of Texas. University of Texas at Dallas. Richardson, Texas. xv + 1881 pp. Freeman, C.C. 1989. Rare plants of the Cimarron National Grassland, Kansas, Final Report. Reports of the State Biological Survey of Kansas. Lawrence, Kansas. ix + 238 pp. Freeman, C.C. 2000. Floristic surveys of Cheyenne, Kiowa, Kit Carson, and Lincoln Counties, Colorado. Unpublished report submitted to the Colorado Natural Areas Program. 63 pp. Freeman, C.C. in prep. Checklist of the Vascular Plants of the Grassland Biome of Central North America. Great Plains Flora Association. 1977. Atlas of the Flora of the Great Plains. Iowa State University Press. Ames, Iowa. xii + 600 pp. Kaul, R.B. 1991. Cactaceae, pp. 153–160 in Great Plains Flora Association, Flora of the Great Plains. University Press of Kansas. Lawrence, Kansas. vii + 1402 pp. Kinraide, T.B. The ecological distribution of cholla cactus (Opuntia imbricata (Haw.) DC.) in El Paso County, Colorado. Southw. Nat. 23: 117–134. McFarland, J.D., P.G. Kevan, and M.A. Lane. 1989. Pollination biology of Opuntia imbricata (Cactaceae) in southern Colorado. Canadian J. Bot. 67: 24–28. McGregor, R.L. 1977. Rare native vascular plants of Kansas. Techn. Publ. State Biol. Survey Kansas 5: 1–44. Martin, W.C. and C.R. Hutchins. 1980. A Flora of New Mexico. J. Cramer. Vaduz, Germany. xiii + 2591 pp. Ostlie, W.R., R.E. Schneider, J.M. Aldrich, T.M. Faust, R.L.B. McKim and S.J. Chaplin. 1997. The Status of Biodiversity in the Great Plains. The Nature Conservancy. Arlington, Virginia. xii + 326 pp. Shaw, R.B., S.L. Anderson, K.A. Schulz and V.E. Diersin. 1989. Floral inventory for the USA army pinon canyon maneuver site, Colorado (USA). Phytologia 67: 1–42. Weber, W.A. and R.C. Wittman. 2001. Colorado Flora: Eastern Slope (3rd Edition). University Press of Colorado. Boulder, Colorado. xl + 521 pp. Weber, W.A. and R.C. Wittman. 2001. Colorado Flora: Western Slope (3rd Edition). University Press of Colorado. Boulder, Colorado. xxxvii + 488 pp.

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