MONTANA STATE This -cover" page added by the Internet Archive for formatting purposes SURVEY FOR OUERCUS MACROCARPA IN THE POWDER RIVER RESOURCE AREA MILES CITY DISTRICT BUREAU OF LAND MANAGEMENT MONTANA Prepared for: Bureau of Land Management Miles City District Office P.O. Box 940 Miles City, MT 59301-4331 Prepared by: Bonnie L. Heidel Montana Natural Heritage Program 1515 E. Sixth Avenue Helena, MT 59620 Assistance Agreement E950-A1-0006 Task Order #13 STATE DOCUMENTS COLLECTION JUL 01993 RETURN F&l^aii!"1\^'-^ ;^* F•--^ Z" \\«M I ^^ ' *• • "HMEOLNETN1A5AN1.5AM1SO.TNA6TtTAhENAALVIE5B.R9A6R2Y0 © 1993 Montana Natural Heritage Program This document should be cited as follows: Heidel, B. 1993. Survey for Ouercus macrocarpa in the Powder River Resource Area, Miles City District, Bureau of Land Management, Montana. Montana Natural Heritage Program, Helena, MT. 12 pp. TABLE OP CONTENTS EXECUTIVE SUMMARY INTRODUCTION 1 STUDY AREA AND METHODS 1 GENERAL SPECIES AND SITE INFORMATION CLASSIFICATION 3 PRESENT LEGAL OR OTHER FORMAL STATUS 3 DESCRIPTION 3 GEOGRAPHIC DISTRIBUTION 5 HABITAT 7 POPULATION BIOLOGY 9 POPULATION ECOLOGY 10 RESULTS AND DISCUSSION 11 LITERATURE CITED 12 APPENDIX 1. BLM field evaluation tract summaries APPENDIX 2 Preliminary Alzada Oak vascular plant checklist APPENDIX EOR printout and map of Alzada Oak stand 3 APPENDIX 4 Aerial photographs of Alzada Oaks area showing BLM tracts FIGURES Figure 1. BLM tracts with woody cover in Alzada Oak area Figure 2. Ouercus macrocarpa close up Figure 3. Ouercus macrocarpa habitat in Alzada Oak area Figure 4 Rangewide distribution of Ouercus macrocarpa . EXECUTIVE SUMMARY Ouercus macrocarpa (bur oak) a sensitive plant species on the , draft Bureau of Land Management sensitive plant list for Montana, was systematically surveyed in the Powder River Resource Area of the Miles City District. Scattered BLM tracts in the Alzada area south of Thompson Creek were screened. Four of the BLM tracts in the area contain Ouercus macrocarpa together making up . ca. 1% of the local oak stand. The stand was mapped as extending over 10 miles in length, as a series of groves with major discontinuities. Conservation status information for Ouercus macrocarpa was compiled in the course of the study and the BLM tracts evaluated relative to conservation concerns and needs. ACKNOWLEDGEMENTS Funding for this project was provided by the Bureau of Land Management. The help and interest of Don Heinze, Dan Bricco, Louise de Montigny, Kent Bowen and Dan Hinckley is gratefully acknowledged. This study builds on the Alzada Oaks stand evaluations originally conducted by Peter Lesica for The Nature Conservancy and the Tenmile Creek Draw stand evaluation conducted by Rob Develice and Lisa Roe through the Montana Natural Heritage Program. . I. INTRODUCTION This study was initiated to update conservation status information on Quercus macrocarpa with particular reference to its occurrence on lands administered by the USDI Bureau of Land Management (BLM) The species is ranked as sensitive on the . draft list of sensitive plant species by the Bureau of Land Management in Montana (USDI Bureau of Land Management 1992). Two primary areas were in the original study design, the Alzada area in Carter County and a woody draw on the south side of the Tenmile Creek valley in Prairie County, both in the Powder River District. The latter was omitted when it was determined that the presence of Quercus macrocarpa was the result of planting. A site evaluation memo is provided on the latter separate from this report. This final report details Alzada area survey procedures and results, statewide species conservation status (modified from Henifin et al. 1981) and significance of results to state , species conservation. II. STUDY AREA AND METHODS The study area is located southwest of Alzada and south of Thompson Creek in Carter County, in the far southeastern corner of the state. All BLM tracts south and west of Alzada were considered, but only tracts with trees were evaluated in the field (Figure 1) Most of the study area is made up of a series of ridges extending into Wyoming. Physical and biological characteristics of the area are described under background species information. BLM color aerial photographs (2 inches to the mile; flown 7-3-79) were used in conjunction with USGS 7.5' topographic maps to determine the location of forested areas, and tentatively distinguish between deciduous and evergreen canopy. The maps and aerial photograph frame numbers used are listed as follow: USGS map BLM aerial photo (Flight line 24 MT 79) Alzada 1-1-16, 1-1-17 Comer Draw gap, 1-1-22, 1-1-24 Cochran Reservior 1-1-24 In addition, a Nature Conservancy site evaluation of the Alzada Oaks area (Lesica 1986) was consulted for preliminary boundaries, floristic inventory, and conservation observations. BLM tracts without trees present were deleted from consideration. This included the majority of BLM administered lands in the area. <0 Q) U ta X o(0 (0 TJ (0 N iH c V4 Q) > O O >i o o (0 o (0 u •p S 1-. ; CQ 0) 3 •H . . . Almost all wooded BLM tracts are within two miles of the Montana- Wyoming state line, but not all within this zone have trees. Six tracts with woodland cover were visited on 27 August 1992 to characterize the extent of Ouercus macrocarpa and note condition (Figure 1) . In the course of this work, stand boundaries were also refined, and consideration was given to the impact of recent mining activity, to update species' and site conservation status information. III. GENERAL SPECIES AND SITE INFORMATION A. CLASSIFICATION 1. SCIENTIFIC NAME: Ouercus macrocarpa Michx. 2. COMMON NAME: Bur oak, mossy-cup oak 3. FAMILY: Fagaceae (Beech) 4. GENUS: The genus Ouercus is a circumboreal genus of temperate and montane-tropical latitudes, spanning the Northern Hemisphere, characterized by a single fruit (acorn) subtended by the cuplike involucre. 5. SPECIES: Ouercus macrocarpa is in the Lepidobalanus subgenera commonly referred to as the white oak group, characterized by rounded leaf lobes. Its species name refers the exceptionally large (macro) acorn (carpa; Figure 4) B. PRESENT LEGAL OR OTHER FORMAL STATUS 1. FEDERAL STATUS A. U.S. FISH & WILDLIFE SERVICE: None. B. BUREAU OF LAND MANAGEMENT: Sensitive on draft list of Bureau of Land Management in Montana (USDI Bureau of Land Management 1992) 2. STATE: Ouercus macrocarpa is currently listed by Montana Natural Heritage Program (1993) as endangered in the state (state rank = SI) This is based on the fact that only one native stand is known in the state, and that there are threats to the stand. This recognition does not afford any form of legal protection.