30 



a short distance to the north of RathcJrum, Kootenai Co. The 

 time oocx^jied in the vicinity of tids canp was from July 20 

 to July 25. The plaints collected were numbered 670 to 740. 

 The region explored wcis the vicinity of Rathdrum, lake 

 Tesemini, and Mud Lake." 



Habitat information on the Sandberg label states "floating 

 in subedpine lakes." After reviewing topographic maps for 

 the Spirit Lake area, it was determned that no subcilpine 

 lakes exist in the Spirit Lake watershed. Subcilpine 

 elevaticxTs are reached an the eastern slopes of Mt. Spokane, 

 Washington, at the head of Brickel Creek, but no lakes occur 

 there. Sandberg, it appears, had a bad reputation among his 

 contenporciries cind wais ceureless in his note-taking. Leiberg 

 reported in a letter to C.V. Piper (cited in Mack 1988) that 

 Sandberg 's r^xjrt of 1892 (Holzinger 1895) erred by as much 

 as 240 km in the location of sane specimens. 



A search was conducted in the vicinity of Spirit LaJ<e during 

 June 1988, eind while suitable haJaitat exists in the area, 

 no H. aquatilis populations were found (Appendix A, p. 152) . 



6. liscatlcns known or suspected to be erroneous reports: 



a. Oolunfcia River Gorge (two sightings, considered to be 

 misidentifications by the Oregon Natural Heritage Data 

 Base (S. Vrilakas, pers. ocm.). 



1. U.S.A., Oregon, Vasco County. 



2. Latitude, Icxigitude, altitude: unknown. 



3. Leged description: unknown. 



4. USGS quad: unknown. 



5. Year of observatic»i: unknown. 



6. Lcx^ation: unknown. 



C. Biogeographical and phylogenetic history: Details unknown, and 

 not yet investigated. It has been speculated that the widely 

 scattered distribution of H. aquatilis may be due to the 

 wanderings of migratory waterfowl (Meinke 1982) . The 

 distributicMTal pattern of H. aquatilis in Montana is undoubtedly 

 related in part to the glacial history of the Swan Valley. The 

 valley floor was glaciated approximately 10,000 years ago, and 

 memy of the pothole ponds and wetlcinds were formed v^xjn retreat 

 of the glacier. Thus, it is possible that the present 

 distribution pattern of the species in Montana was recently 

 established. In Washington, all but one of the known extant 

 sites occur in the channeled scablands, which were formed by the 

 Bretz floods (J. Gamcai, pers. ocmm.). 



General envirorment and habitat description. 



A. Concise statement of general envirorment eind habitat: Howell ia 

 aquatilis is an aquatic plant occurring in small pothole ponds 

 or the quiet water of retired river oxbows. These wetleinds 



