The Vascular Plant Floristics of Denali National Park and Preserve A Summary, Including the Results of Plant Inventory Fieldwork 1998-2001 National Park Service Inventory and Monitoring Program Central Alaska Network The Vascular Plant Floristics of Denali National Park and Preserve A Summary, Including the Results of Plant Inventory Fieldwork 1998-2001 Carl A. Roland Denali National Park and Preserve P.O. Box 9, Denali Park, AK 99709 March, 2004 National Park Service Central Alaska Network Inventory and Monitoring Program N.P.S. Final Technical Report CAKN-04-01 Funded by the National Park Service Inventory and Monitoring Program Abstract ABSTRACT Carl A. Roland 2004. The Vascular Plant Floristics of Denali National Park and Preserve: A Summary, Including the Results of Inventory Fieldwork 1998 - 2001. Denali National Park and Preserve, P.O. Box 9, Denali Park, Alaska, 99755. A reconnaissance inventory of the vascular plant flora of Denali National Park and Preserve was conducted during the period 1998-2001. The primary goal of this project was to synthesize existing floristic information with the results of targeted original inventory field work in order to produce a voucher-based list of the vascular plant species that occur within the Park. In order to accomplish this fundamental goal of documenting the flora of Denali National Park and Preserve there were five major objectives that needed to be met: 1) to assemble all available pre-existing floristic data into a highly functional database; 2) to assess the strengths and weaknesses of this existing data set and identify geographic and taxonomic gaps in our knowledge of Denali National Park and Preserve’s flora; 3) to perform targeted vascular plant inventory fieldwork in order to effectively fill the existing data gaps and to assemble a complete, voucher-based vascular plant flora for Denali National Park and Preserve; 4) to create a GIS data layer delineating the floristic regions of Denali National Park and Preserve, and to summarize and present all existing floristic information available for the Park in this context; 5) to synthesize the results of both existing and new floristic investigations from original field work into a report describing the state of our knowledge concerning the vascular plant floristics of Denali National Park and Preserve. Vascular plant inventories were performed documenting the flora of 197 sites across the landscape of Denali National Park and Preserve. This set of sites included a broad cross-section of habitats from aquatic communities in large boreal lakes to high alpine scree slopes. I estimate that approximately 1,358 hours of actual survey time were spent in the field recording plant species occurrences and making voucher collections. Over 4,000 plant specimens were collected as a part of this study, and a total of 3,793 permanent voucher specimens were prepared from these collections. The set of specimens collected during this inventory documents the occurrence of about 622 separate vascular plant species within the Park (which represents approximately 83 percent of all of the species presently known to occur there). This collection represents an addition of 224 plant species and 246 separate taxa (including subspecies and varieties) to the vouchered vascular flora of the Park, as compared to the list of taxa known to occur in the Park that was prepared in 1996-7. In addition, this set of new taxa represents 52 genera and 14 families of plants that were not known to occur in the Park prior to 1998. Two hundred and thirty-five specimens of forty-six different taxa considered rare in Alaska by the Alaska Natural Heritage Program (AKNHP) were collected during this inventory. Eight of these taxa had an AKNHP State-level rarity rank of S2 or lower. The Vascular Plant Floristics of Denali National Park and Preserve i Abstract The Vascular Plant Floristics of Denali National Park and Preserve ii Executive Summary EXECUTIVE SUMMARY Chapter One: Introduction • The subject of this report is the results of a vascular plant inventory project that occurred in Denali National Park and Preserve, Alaska, from 1998 to 2001. • This document summarizes the current state of knowledge of the distribution and composition of the vascular flora of Denali National Park and Preserve. • The principal goal of this project was to compile a complete, voucher-based list of the vascular plant taxa that occur in the Park through examination of existing data and targeted field inventory work. • The total project-specific cost of this work (excluding the Principal Investigator’s salary) was approximately $130,000 over a four year period, including all aspects of the work. • The steps that were completed in preparation for conducting the new field inventories that would complete the Floristic Inventory Project were to: o create a relational database for storing, analyzing and presenting floristic data; o review the existing literature and collection data to develop an “expected” species list for the Park, and integrate this list into the floristic database; o identify geographic, taxonomic and habitat gaps in existing floristic data for the Park; o develop a strategy for efficient allocation of fieldwork and accomplishing the goals of this project. • Fieldwork for the project was performed each summer during the period 1998-2001. Chapter Two: Overview and Description of the Study Area • Denali National Park and Preserve is located within the south central section of mainland Alaska. It occupies the area spanning roughly 62° 18’ and 64° 04’ North latitude and between 148° 48’ and 152° 52’ West longitude. • The Park preserves 2.4 million ha of intact subarctic ecosystems; the maximum latitudinal extent of the Park spans about 200 km north to south, and similarly the longitudinal extent of the Park spans about 200 km from east to west. • Physiography varies dramatically across the Park landscape from ice-covered alpine peaks, to several ancient, weathered low ranges of hills, to lowland boreal basins. The Vascular Plant Floristics of Denali National Park and Preserve iii Executive Summary • The Alaska Range mountains are the central element of the Park landscape, both aesthetically (they dominate the horizon, even from the deep lowlands of the Minchumina Basin), and through their crucial role in dominant landscape processes. • The Alaska Range alpine landscape is characterized by steep, barren rock escarpments and thick sheets of glacial ice. Permanent ice occupies most surfaces above 2,300 meters elevation throughout the range. • There are three primary lowland regions of the Park, two are north of the Alaska Range – the Toklat Basin and the Yukon-Kuskokwim lowlands, and one is south of the Range – the Cook Inlet lowlands. • Whereas the core of the Alaska Range was formed by igneous intrusions of granitic rock, much of the accessible terrain in the alpine region, and that hospitable to plant life, is composed of rock that is sedimentary, or meta-sedimentary in origin. Significantly for plant life, small areas of calcareous sedimentary rock, including limestone and marbleized limestone, crop up on both the southern and northern parts of the range. • The primary macroclimatic gradient in the Park is the interface between the relatively warm and moist maritime air masses that are generated in the Gulf of Alaska and the dry, highly continental air masses that occur north of the Alaska Range. Moist maritime air masses move onshore with atmospheric currents and collide with southern flanks of the Alaska Range, where they cool and cause high precipitation and considerable cloudiness south of the Alaska Range crest. Climate conditions north of the crest, conversely, are highly continental. • Vegetation patterns in the subarctic are strongly controlled by environmental factors that vary with topographic variables such as slope, aspect and elevation. • The ecological history of the Denali National Park and Preserve region during the past two million years is characterized by repeated advances and subsequent retreats of massive sheets of glacial ice throughout the Pleistocene Epoch. These repeated and enormous ecological upheavals have had profound influences on the nature of the biota resident in the Park and the very nature and shape of the Park landscape itself. • Twenty three different ecological units at the level of the ecoregion subsection were defined for Denali National Park and Preserve. Chapter Three: History of Plant Collecting in Denali National Park and Preserve • The flora of the Park road corridor area of Denali National Park and Preserve has been collected more intensively than most regions of Alaska. • The history of plant collecting in the Park includes work by many of the leading botanists in the history of the botanical exploration of Alaska, such as Lawrence J. Palmer, A. Erling The Vascular Plant Floristics of Denali National Park and Preserve iv Executive Summary Porsild, Jacob P. Anderson, Eric Hultén, Olav Gjaerevoll, Stanley L. Welsh, Leslie A. Viereck, and David F. Murray. • The focus of this summary is on broad-spectrum vascular plant collections that contributed substantial information about the composition of the vascular plant flora of this area. Chapter Four: Methods • This inventory was a targeted reconnaissance survey of the vascular plant flora. The size of the study area, in combination with strict budget constraints, meant that a premium was put on efficient site selection for this project (relative to acquiring new records of plant species