Journal of the Oklahoma Native Plant Society, Volume 2, Number 1, December 2002 54 Oklahoma Native Plant Record Volume 2, Number 1, December 2002 Schoenoplectus hallii and S. saximontanus 2000 Wichita Mountain Wildlife Refuge Survey Dr. Lawrence K. Magrath Curator-USAO (OCLA) Herbarium Chickasha, OK 73018-5358 A survey to determine locations of populations of Schoenoplectus hallii and S. saximontanus was conducted at Wichita Mountains Wildlife Refuge in August and September 2000. One or both species were found at 20 of the 134 locations surveyed. A distinctive terminal achene character was found specifically that the transverse ridges of S. hallii appeared to be rounded and S. saximontanus appeared to be rounded with a projecting narrow wing. Basal macroachenes have not yet been properly described but are borne singly at the base of each culm and are about 3-4 times larger than the terminal achenes. It is speculated that amphicarpy may be related to grazing pressure, the basal macroachene being produced even if the upper portion is consumed, as a response to grazing. Both species are grazed/disturbed by bison, elk, and longhorns on the Refuge. Introduction A survey to determine locations of populations of Schoenoplectus hallii (A. Gray) S.G. Smith (Hall’s bulrush) and S. saximontanus (Fernald) J. Raynal (Rocky Mountain bulrush) was conducted on the Wichita Mountains Wildlife Refuge during late August through September 2000. The survey team members were myself, Sam Waldstein, Refuge Manager; Chip Kimball, Range Biologist; and Bob Timberman, Biology Technician. Sites selected for observation were areas similar to the Jed Johnson Dam habitat, which is the site of the original collection of S. hallii made in 1987. Selection of sites to be surveyed was done by WMWR team members. The three Sundays spent in the field were some of the hottest of the season with temperatures ranging from 100o to 110oF. General Observations The presence of Schoenoplectus halllii and S. saximontanus at the various sites sampled. represent, for the most part, a response to the drawdown of water levels in the various lakes and ponds. The plants seem to occur mainly on Magrath, L.K. https://doi.org/10.22488/okstate.17.100013 the drawdown mud, sand, or gravel flats. However in some places they occur in shallow water up to a depth of about a foot [30.5cm]. They seem to compete with perennial emergent plants and with most emergent annuals. In addition to the 36 sites that I personally examined, WMWR staff examined an additional 98 sites with similar habitat and found no Schoenoplectus present. Schoenoplectus occurred in only 20 of the 134 sites (14.93%). Of those 134 sites, 4 had both species present (3%), 14 had S. halllii present (10.45%) and 10 had S. saximontanus present (7.46%) (see Table). Based on the WMWR observations, it is strongly advised that the adjacent area of Fort Sill should be inventoried since these two species are, most likely, present there. However, Rahmona Thompson who has conducted plant surveys at Fort Sill has not found either species at this time (pers. comm. 2002). At several of the sites plants had been uprooted as a result of trampling by bison and other animals in the mud flat areas. The number of uprooted plants ranged between 0.0% and 1.0% at those Oklahoma Native Plant Record 55 Volume 2, Number 1, December 2002 Magrath, L.K. locations, but in general was less than .05%. While this obviously does cause some damage to populations in localized areas the damage appears to be negligible and it is even possible that it may be an important transport method of matured achenes to previously uncolonized areas. This could readily be accomplished by mud containing seeds or inflorescences with seeds adhering to the hooves, hair, or skin of the lower part of the animals’ legs. There appear to be three useful characters associated with the achenes that can be used to separate the two species: style branching, achene cross section, and transverse ridges. S. hallii S. saximontanus Style Branches mostly bifid trifid Achene cross section unequally biconvex (1 of 2 sides may be flat) Trigonus (3-sided) Transverse ridges rounded mostly rounded with narrow wing To my knowledge, “Transverse ridges” has not been mentioned in the literature on these two taxa. McKenzie (1988) does not mention this character in his status assessment report on S. hallii, nor does Yatskievych (1999) in Steyermark’s Flora of Missouri. Dr. Marian Smith at Southern Illinois University is working on both terminal achenes and basal macroachenes using Scanning Electron Microscopy and more precise measuring techniques (pers. comm. 2001). So this may be a new useful character to separate these two taxa. (see Figures). McKenzie (1998) reports that “heavy grazing has been noted at sites in Kansas, Missouri, and Wisconsin but it is not known whether this disturbance negatively impacts the species…” It is my hypothesis that amphicarpy may well be a response to heavy grazing pressure disturbance by native grazing animals such as bison, elk, and deer prior to the introduction of exotic grazers such as cattle, horses and sheep by European settlers. It would be a way that the plant could insure seed production even if it is heavily grazed and the terminal achenes damaged or destroyed. The observation that the plant produces only a very limited number of basal macroachenes (one per culm) with significantly more food reserves per achene would seem to support this interpretation. The smaller, more numerous terminal achenes would offer a relatively easy method for seeds to be transported farther distances and to new sites while the macroachenes would provide an excellent way to persist in presently occupied sites. The number and identification of the two species at sites where both occur could be somewhat problematic. S.G. Smith and A. E. Schuyler independently identified a hybrid from WMWR that was collected by M. Smith and McKenzie July 28, 2002 as the first documented, putative hybrid of the two species ever recorded. [USA Oklahoma: Comanche Co., WMWR, 28 July 02, P. McKenzie 2028 pers., WIS, MO] (pers. comm. McKenzie 2002; Smith 2002). There obviously needs to be further research done to confirm or deny this hypothesis as well as possible hybridization between the two species at the Refuge. Voucher Specimens of Schoenoplectus hallii and S. saximontanus resulting from this study are kept in the USAO Herbarium (OCLA) at the University of Science and arts of Oklahoma in Chickasha, Oklahoma. 56 Oklahoma Native Plant Record Volume 2, Number 1, December 2002 Magrath, L.K. FIG. (a) and (b) Fruit and inflorescence of Schoenoplectus saximontanus (Steyermark’s Flora of Missouri, 1999. Used by permission). FIG. (e), (f), and (g) Fruit, inflorescence, and habit of Schoenoplectus hallii (Steyermark’s Flora of Missouri, 1999. Used by permission). Oklahoma Native Plant Record 57 Volume 2, Number 1, December 2002 Magrath, L.K. TABLE Schoenoplectus occurrence in thirty-six survey sites August and September 2000 (based on achene characteristics of the two species) Site # Description & Date abundance/# collected/voucher# S. hallii S. saximontanu 1-Pond 27-Aug Draw-down mudflat around pond Some plants grazed, some uprooted Some dried out on shore Few floating in water still alive 0 scat/8/21254 2-Pond 27-Aug Draw-down mudflat 0 0 3-Pond 27 Aug Draw-down mudflat 0 0 4-Corral area 27 Aug Stream with draw-down mudflat Utricularia observered 0 0 5-Kiowa Lake 27 Aug Draw-down mud flat around pond Some plants grazed, some uprooted Some dried out on shore Few floating in water still alive 0 scattered/4/21259 6-Wing Pasture west of creek 27 Aug Draw-down mud flat around pond Some plants grazed 0 rare/12/21261 7-Buford Lake 27 Aug Draw-down mud flats Utricularia and Nelumbo abundant 0 0 58 Oklahoma Native Plant Record Volume 2, Number 1, December 2002 Magrath, L.K. 8-Quanah Parker Lake 27 Aug Near Nature Center Draw-down mud flat around pond scat/6/21263 0 9-New Pond by Crater Lake 27 Aug South of Visitor Center Draw-down mud flat 0 0 10-Pond at Sulphur Trap Corrals 27 Aug East of Visitor Center Draw-down mud flat 0 0 11-Pond in Sulphur Trap 27 Aug North of Visitor Center Draw-down mud flat around pond 0 0 12-Jed Johnson Lake 18 Aug 8 identifiable plants. Not collected Plants just coming into bloom Original site for the original Collections for WMWR rare/0/- 0 27 Aug 8 identifiable plants No collections made rare/0/- 0 13-Crater Lake 27 Aug Draw-down mud flat Apparently too much perennial vegetation present 0 0 14-West Gate Pond 3 Sep Draw-down mud flat Apparently too much perennial vegetation present 0 0 15-Comanche Lake 18 Aug Draw-down mud flat scat/2/21237 0 Oklahoma Native Plant Record 59 Volume 2, Number 1, December 2002 Magrath, L.K. 3 Sep Draw-down mud flat Mixed populations scat-loc com/24/21272 scat-locom/83/27271 16-Grama Lake near dam & Gram Flat 18 Aug Draw-down mud flat Several hundred plants Numerous basal rosettes in shallow water (20-30 cm) 0 scat/3/21236 3 Sep Mixed populations on draw-down Several hundred plants Numerous submerged basal rosettes in shallow water (20-30 cm) scat-loc com/48/21274 scat-loc com/15/21273 10 Sep Revisit & complete walk-around Both present on draw-down mud flat Several thousand plants Dominant plant in a few places Numerous basal rosettes present in shallows in several areas scat-loc abd/211/21216 scat/99/21322 17-Hollis Lake 3 Sep Apparently too much perennial vegetation in draw-down zone 0 0 18-Pond 0.5 mile west of Hollis 3 Sep com-loc abd/300+/21278 0 19-Pond 3 Sep Draw-down mudflat 0 0 20-Pond 3 Sep Draw-down mudflat 0 0 21-Boggy Flats 18 August 2000 Draw-down mudflat around pond Some plants grazed or uprooted Some dried out on shore Few floating in water still alive First located by Sam Waldenstein on Aug 17, 2000. 0 loc abd/x/21231 60 Oklahoma Native Plant Record Volume 2, Number 1, December 2002 Magrath, L.K. Sun 3 September 2000 Draw-down mud flats on ponds 0 loc abd/5/21280 22-Pond southwest of Grace Mountain 3 Sep Draw-down mud flat Water-clover fern present 0 0 23-Cut Throat Lake 3 Sep Draw-down mud flat Water-clover fern present Beautiful clear water and bass 0 0 24-Northwest Corner of Pinchot Loop 3 Sep Draw-down mud flat around pond 0 0 25-Barow Pit east side of Pinchot Loop 3 Sep Draw-down mud flat around pond 0 0 26-Straight east of site 25 3 Sep Draw-down mud flat around pond Bacopa present scat/8/21287 0 27-Medicine Tank 3 Sep Draw-down mud flat around pond Colonial Bryozoan Pectinatella magnifica Leidy in shallow water by dam Identification by Dr. Mike Mather, USAO common/12/21290 scat/3/21289 28-West Gate Road, Buffalo Gap 10 sep Draw-down mud flat around pond Bacopa present 0 scat/11/21303 29-Winter Valley at end of Wing Fence at Hot Trap 10 Sep Draw-down mud flat around pond Mixed collection not discovered until laboratory observations were made. rare/3/21304 in part* rare/6/21304 in part* Oklahoma Native Plant Record 61 Volume 2, Number 1, December 2002 Magrath, L.K. 30-Winter Valley southeast fo Road 10 Sep Draw-down mudflat around pond Bacopa present scat/2/21305 0 31-North end of Research 10 Sep Draw-down mud flat around pond Bacopa present 0 scat/14/21306 32-Pond in Exhibition Pasture 10 Sep Pond in Exhibition Pasture Draw-down mud flat one plant/0/0 0 33 Ingram House Pond 10 Sep Draw-down mud flat Several hundred plants Bacopa present scat-loc com/19/21309 0 34-Quanah Parker 10 Sep Near dam Draw-down mud flat Several thousand? plants scat-loc com/54/21210 0 35-Quanah Parker 10 Sep SE of Environmental Center Draw-down mud flat Several hundred plants scat-loc com/7/21313 scat-loc com/25/21311 36-Elmer Thomas Lake 10 Sep Draw-down mud flat along north shore scat-loc abd/46/21314 0 Key to abundance descriptors rare = fewer than 10 plants at site scat = scattered, a few plants occurring over several square meters common = many plants occurring over several square meters abundant = large numbers of plants (often the local dominant plant) loc com = many plants in a small area, but may be scattered over a large area loc abd = large numbers of plants in small area, but may be scattered over a large area 62 Oklahoma Native Plant Record Volume 2, Number 1, December 2002 Magrath, L.K. References McKenzie, Paul M. 1998. Hall’s Bulrush (Schoenoplectus hallii) Status Assessment. U.S. Fish and Wildlife Service. Columbia, MO. Yatskievych, George. 1999. Steyermark’s Flora of Missouri, Vol 1, rev. ed. Missouri Dept. of Conservation in cooperation with the Missouri Botanical Garden Press. St. Louis, MO. Editor’s Note: Exact locations of individual sites were determined by GPS and are recorded in the WMWR database. However, that information and access to the sites is strictly limited and permission must be requested from the refuge manager. Oklahoma Native Plant Record 63 Volume 2, Number 1, December 2002 Magrath, L.K. Wichita Mountains Wildlife Refuge, Comanche County Echinocerus baileyi on Elk Mountain Trail (photos by Sheila Strawn)