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Aquatic and Wetland Vascular Plants of the Northern Great Plains

Using the Manual


This treatment is composed of taxonomic keys and plant descriptions to facilitate identification of about 500 vascular plants encountered in wetland habitats of the northern prairie region. Many taxa are also illustrated with a line drawing or photograph to help the user conceptualize what is being described. Most taxa are not illustrated; but for those which have illustrations, the figures are often not detailed enough to be diagnostic. Consequently, illustrations alone should not be relied upon to make species determinations. Rather, the keys and descriptions must be used carefully in conjunction with illustrations to ensure proper identifications. The terminology used in keys and descriptions is necessarily botanical, because to distinguish between the various kinds of plants requires observing traits that are technical by nature. Those unfamiliar with descriptive terminology of plants will find it helpful to consult the Glossary of Botanical Terms, relevant illustrations, and the lead-in descriptions of genera and families. A hand lens or binocular microscope, a 15-cm ruler with mm scale, and dissecting implements will also help because discerning between closely related plant taxa almost always entails close inspection and careful measurement of plant structures.

Included with the species descriptions in the manual are (1) common name(s), if available; (2) flowering/fruiting periods (or periods when spore-producing structures are present in ferns and fern allies); (3) habitat descriptions; (4) accounts of regional and range-wide distributions; and (5) nomenclatural synonyms for those species treated under other names in recent works. Official U. S. Post Office abbreviations for states are used to describe distributions in the United States; standard abbreviations are used for Canadian provinces, foreign countries, and geographical regions. The nomenclature and taxonomic concepts are largely those of the Flora of the Great Plains (Great Plains Flora Association 1986) except where otherwise noted. The ordering of plant families also follows the Flora; genera and species are alphabetically ordered within family treatments. Notes on related taxa rarely encountered in regional wetlands, or other items of interest, are sometimes included in a paragraph following the appropriate species description.

The regional range distribution map for each species shows the plant's occurrence on a county by county basis as documented by voucher specimens in regional herbaria. Each dot on a map represents at least one herbarium specimen of the plant from the dotted county in the region. Besides the many specimens collected for this study, a major resource for development of distribution maps was the Atlas of the Flora of the Great Plains (Great Plains Flora Association 1977). Another source of distributional information was Vascular Plants of Minnesota: A Checklist and Atlas (Ownbey and Morley 1991). For a few species, maps in the Great Plains Atlas are incorrect because they are at least partly based on misidentified specimens. The distribution maps shown herein are thus updated. The diagnostic keys to taxa in the manual are strictly dichotomous, meaning that the user must choose between two leads at each step in the key. The two leads (called a couplet) always share the same number and describe contrasting characteristics or conditions. The user must determine which one of the two leads applies to the plant being identified. Once this determination is made, the next couplet directly below the chosen lead is considered in the same manner, and a choice is made between the two leads of that couplet. The process continues until the taxon (the particular family, genus, and ultimately, the species) to which the plant belongs is determined.

The traits used as key characters are those considered most readily observable, yet least likely to cause errors in identification. The use of technical terms and reference to minute traits are unavoidable in many instances, especially in the treatments of the more complex and specialized taxa like the grasses (Poaceae), sedges (Cyperaceae), and composites (Asteraceae). Specialized structures are described and often illustrated in the treatments of families and genera where they are found.

The key in the following section is a key to the plant families represented in the regional wetland flora. This key will direct the user to the appropriate family treatment, and often (in parentheses) to a particular genus or species within the manual. Keys to genera and species are provided within each family treatment wherever there are two or more different possibilities. With practice and a gained familiarity with plant characters, the keying process becomes easier and faster. The family and genus keys can even be bypassed once one is able to recognize families and genera on sight.


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