VASCULAR PLANTS of MINNESOTA This page intentionally left blank VASCULAR PLANTS of MINNESOTA A Checklist and Atlas Gerald B. Ownbey and Thomas Morley UNIVERSITY OF MINNESOTA MINNEAPOLIS • LONDON The University of Minnesota Press gratefully acknowledges the generous assistance provided for the publication of this book by the Margaret W. Harmon Fund Minnesota Department of Transportation Minnesota Landscape Arboretum Minnesota State Horticultural Society Olga Lakela Herbarium Fund—University of Minnesota—Duluth Natural Heritage Program of the Minnesota Department of Natural Resources Copyright © 1991 by the Regents of the University of Minnesota. First paperback printing 1992 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Published by the University of Minnesota Press 2037 University Avenue Southeast, Minneapolis, MN 55455 Printed in the United States of America on acid-free paper Library of Congress Cataloging-in-Publication Data Ownbey, Gerald B., 1916- Vascular plants of Minnesota : a checklist and atlas / Gerald B. Ownbey and Thomas Morley. p. cm. Includes bibliographical references and index. ISBN 0-8166-1915-8 1. Botany-Minnesota. 2. Phytogeography—Minnesota— Maps. I. Morley, Thomas. 1917- . II. Title. QK168.096 1991 91-2064 582.09776-dc20 CIP The University of Minnesota is an equal-opportunity educator and employer. Contents Introduction vii Part I. Checklist of the Vascular Plants of Minnesota 1 Pteridophytes 3 Gymnosperms 6 Angiosperms 7 Appendix 1. Excluded names 81 Appendix 2. Tables 82 Part II. Atlas of the Vascular Plants of Minnesota 83 Index of Generic and Common Names 295 This page intentionally left blank Introduction The importance of understanding the vegetation of al distributional comments. Morley's Spring Flora an area opening to Europeans was appreciated even (1974) contains written distribution descriptions, and as settlement was occurring. Thus publications con- maps are provided in Lakela's Flora and Coffin and cerning plants found in various parts of Minnesota Pfannmuller's book on endangered plants and animals appear as early as 1822. Upham (1884) and Mac- (1988). The maps in the Great Plains Atlas (1977) in- Millan (1892) give an accounting of these articles. clude only the western two-fifths of Minnesota. The The first comprehensive list of the vascular plants of present atlas is the first complete one for the state. Minnesota is that by Lapham (1875). Lapham Documentation for each kind of plant in the checklist enumerates 896 plants for the state, based chiefly on and each dot on the maps rests on one or more speci- his own observations and collections. In 1884, Up- mens in the University of Minnesota herbarium on the ham published his annotated catalogue of the state's St. Paul campus, and in a few instances on specimens at flora, largely a compilation according to the author, other institutions. The University of Minnesota herbari- in which 1,540 species were listed. Upham's book um was established in 1888 with the acquisition of the contains a very useful introduction with good histor- first set of the large Minnesota plant collection of John ical notes and observations on the state's vegetation. H. Sandberg. The earliest of his specimens dates from The next major listing, MacMillan (1892), includes 1879 according to a survey recently made in the herbari- only the vascular plants of the Minnesota River Val- um of 60 widespread and abundant species. Subsequent- ley. The area involved is slightly over a fifth of that ly, the herbarium grew with the acquisition of other pri- of the state, but 1,165 species are given, well over vate collections. The earliest specimen found in the half the number for the state. survey is dated 1849. The most active early collectors, The next comprehensive work is by Moore and in addition to Sandberg, were C. L. Herrick, J. C. Kas- Tryon (1946), who cited 1,874 species of vascular sube, T. S. Roberts, G. B. Aiton, S. M. Manning, plants. In 1965, an important regional flora was L. R. Moyer and J. M. Holzinger. In 1890 Conway published by Lakela. This book describes the plants MacMillan, head of the Botany Department at the of St. Louis and Lake counties and includes 1,179 University of Minnesota, undertook also to serve as the species. More recently, numerous additions to the state botanist for the Geological and Natural History flora have been made and many changes in nomen- Survey and in that capacity employed C. A. Ballard, E. clature have accumulated in the literature. To pro- P. Sheldon, and B. C. Taylor to make extensive plant vide an up-to-date list of plants, Vascular Plants of collections in the state. The Survey collections (begun Minnesota: A Checklist and Atlas has been pre- by others in 1875) were later transferred to the Botany pared; an entirely new listing, it includes 1,618 na- Department's herbarium. Many persons since that time tive and 392 introduced species, a total of 2,010. have contributed Minnesota material to the herbarium, Knowledge of plant distributions is valuable in including W. D. Frost, W. A. Wheeler, F. K. Butters, plant systematics, plant ecology, and other dis- C. O. Rosendahl, J. B. Moyle, M. F. Buell, O. Lakela, ciplines. Data of this type for Minnesota are only E. C. Abbe, J. W. Moore, G. B. Ownbey, T. Morley, partial in previous publications. Lists of plants for G. A. Wheeler, and W. R. Smith. At present, there are certain sites in the state and for certain counties pro- approximately 97,000 Minnesota specimens in the her- vide distribution information, as do a few mono- barium. graphs of genera at the state level. MacMillan's Part I of this volume was prepared by G. B. Ownbey. work and that by Rosendahl (1955) have very gener- The work entailed an extensive review of the recent INTRODUCTION viii literature in order to determine the correct name for These papers are cited at appropriate places in the each of the taxa, including subspecies, varieties, and checklist. Voss's Michigan Flora (1972, 1985), particu- hybrids of vascular plants found within the state. In the larly Part I, has been drawn upon extensively. The vol- checklist the families appear alphabetically under one of ume by Dore and McNeill (1980) was consulted with the three major groups of vascular plants: the Pterido- great profit on numerous occasions. Several extremely phytes, Gymnosperms, and Angiosperms. Families of useful books on Minnesota Plants should be mentioned the Monocotyledoneae and Dicotyledoneae appear in a here. Among them the most important are Morley single alphabetical sequence under the Angiosperms. (1974), Lakela (1965), Tryon (1980), and Rosendahl The justification for this arrangement is one of utility. (1955). The authors of the present work wish to ac- Recent critical literature, mostly that published since knowledge their deepest obligations to these investiga- 1950, is cited under each genus and sometimes also un- tors and to others too numerous to list individually. At der the family. This practice should assist the user when the same time we assume full responsibility for any er- the reasons for the acceptance or rejection of a particular rors of interpretation, or otherwise, committed in the name in the checklist are at issue. course of the work. An attempt is made to account for all of the plant The mapping project was undertaken by T. Morley in names credited to Minnesota in Fernald (1950) and in 1962 and remained in his charge through the mid-1970s. Gleason and Cronquist (1963). Subspecies and varieties Mapping of all Minnesota specimens then in the Univer- are given when such subdivisions are thought to be val- sity of Minnesota herbarium, at that time about 60,000 id. Interspecific hybrids known to be present in Min- specimens, was completed in 1973. In the later 1970s nesota are also listed under the putative parental combi- the responsibility of mapping the new accessions and nation or under the binomial of the hybrid, if one exists, overseeing the project gradually shifted to G. B. Own- followed by the names of the putative parents. Familiar bey, who brought it to publication. Intensified collecting synonyms from other sources are listed when it is during this period, largely under the auspices of The Na- thought that listing will clarify their standing with re- ture Conservancy and the Minnesota Department of spect to the state flora. For the most part, names of Natural Resources, rapidly increased the number of plants introduced from Europe follow those of the Flora Minnesota specimens and brought on accelerated map- Europea (Tutin et al., 1964-80). A list of excluded ping during those years. names is given at the end of the checklist. Citation of The maps illustrate general repeated patterns of dis- author's names after the binomials mostly follows Fer- tribution as well as patterns peculiar to individual spe- nald in form. Common or vernacular names for both cies. Minnesota's flora represents the western limits of genera and species are listed if they appear well estab- the vast eastern forest flora, and simultaneously lished by usage. Coined or contrived common names represents the northern and eastern limits of the flora of are avoided throughout. the prairies and plains in the continental United States. The listing of species in genera that are notoriously More than anywhere else these two contrasting con- difficult taxonomically must be considered provisional tinental floras meet sharply in the state, and the individu- at best, as must be the distribution maps of these plants. al distributions reflect these broad patterns. The parallel In the Rosaceae, Amelanchier, Crataegus, and Rubus fit arcs of the conifer zone, hardwood forest strip, and this category.