NAZ Flora: A Photographic, Annotated Catalog of Northern Arizona Vascular Plants, published by Mindbird Maps & Books


While the arrangement of this catalog, giving priority to scientific names, renders it more difficult to use by all but intermediate to advanced botanists, there is much of interest to the beginner.  This glossary of basic terms is provided to encourage general readers to gain a better understanding and appreciation of wild plants.
A flowering plant, one of the two major groups of seed plants, the other being the gymnosperms.  As you can see by comparing the numbers of angiosperms in the catalog with other groups, most plants we see are in this group.  Angiosperms differ from gymnosperms in that the seeds are enclosed within the ripened ovary and bear true flowers.
A plant which sprouts, flowers, fruits and dies within a 12 month period.  Most annuals in this region pass through their life cycle in just 5 to 8 months.  A few plants which are usually annual may survive to live several years in favorable conditions, i.e. they may become perennial.
A plant which blooms during the second year of its life cycle.  Some plants which are usually biennial survive to bloom again in their third or fourth year and are termed "short-lived perennials."
Flowers (as a verb), referring specifically to the state of shedding pollen or having a stigma receptive to pollen, or both.  Some plants may retain showy flower parts or associated leaves after pollination (Castilleja, the Indian paintbrushes are an example), but they are no longer blooming if they are not shedding pollen or receptive to pollen.  Other plants have no showy flower parts at all (Quercus, the oaks, are a good example) but still have a blooming period.
botanical illustration
A detailed and scientifically accurate drawing, engraving, or painting of a plant, which gives particular attention to the features which distinguish it from other plants.  (A detailed illustration of a butterfly, though it be in the same style as some botanical illustrations, is most emphatically not one—though I've seen butterfly paintings labeled as such!)
The scientific study of plants, usually including groups traditionally considered plants, such as fungi, which are no longer classified as plants.
An immature flower, leaf, or set of leaves, often enclosed in a cone-shaped structure.
One of the two groups of angiosperms, the other being the monocotyledons.  Dicots (as they are affectionately known for short) are characterized by the presence of only two seed leaves when they first sprout (di = two, cotyledon = seed leaf).  Dicots usually have flower parts in fours and fives, and leaves are usually net-veined rather than having parallel veins.
A broad grouping of life forms believed to have a distant common ancestry, and sharing many general traits.  Families are further subdivided into genera, and genera into species.  The botanical name of a family ends in "-aceae," a suffix which means "family."  Therefore, you would never say "Asteraceae Family" since that would be redundant.
A vascular plant bearing spores (rather than seeds), with flattened leaflike "fronds" further divided.  Some flowering plants (Achillea, yarrow; Chamaebatiaria millefolium, fernbush; and the common house plant "asparagus fern," for example) have leaves which superficially resemble ferns, but they are, in fact, flowering plants and not ferns.
fern allies
A catch-all term for all spore-bearing vascular plants which do not otherwise meet the definition of a fern.  Equisetum, the horsetails or scouring rushes, are an example, as is Selaginella, spike-moss.  The various groups of fern allies are not any closer related to each other than they are to ferns, but it is a convenient term.
The species of plants found in a particular area (in contrast to "fauna", the animals of a particular area; note that even colorful flower-like butterflies are fauna, and not flora!).  Also, a book listing and usually describing the species of plants found in a particular area.
The reproductive structure of a flowering plant, consisting of the pollen-shedding anthers and/or the pollen-receiving stigmas, and usually (but not necessarily) showy petals or sepals which function to attract pollinating insects or birds.
The product of a ripened ovary.  The fruit of a flowering plant is not necessarily fleshy or edible, as we expect the term to mean from every day usage.  Botanically, a pea pod, pumpkin, and even an unshelled sunflower seed are as much fruits as an apple or rose hip.
A group of organisms traditionally included among the plants, but now considered so distinct as to constitute a separate kingdom of their own.  Mushrooms are the best known fungi.  They are not included in the catalog.
A general grouping of organisms sharing more common traits than those of a family, and which is the first part of the scientific name.  The first letter of the name of the genus is always capitalized.  Plural: genera
One of the two groups of seed plants, characterized by seed borne unenclosed or naked (gymno = naked, sperm = seed), and usually having scale-like or thin needle-like leaves, as in the pines.
The general structure of the plant, how it grows: whether creeping, single-stemmed, bushy, leaning, etc.  Also (as in the photo pages) refers to an illustration which shows the habit of the whole plant, rather than just a stem or flower detail.  Not to be confused with "habitat" (see below).
The type of environment in which an organism lives.  Examples are woodlands, cliff faces, streamsides, in ponds, grasslands, etc.
To the botanist, an herb is a plant without woody stems, i.e. not a tree or shrub.  This differs from the use of the word by the cook or herbalist, which designates only those plants with culinary or medicinal properties no matter whether or not the stems are stiffened with wood.
A general term for a cluster of flowers on one plant.  An inflorescence can be very loosely arranged, tightly bunched, or anything in between.
An organism consisting of an outer fungal body enclosing photosynthetic algae.  Since they are not vascular plants, they are not included on the list.
Monocots are the second of the two subgroups of flowering plants, characterized by solitary seed leaves (mono = one, cotyledon = seed leaf) rather than two, and recognized at maturity by usually having flower parts in groups of three and leaves with parallel veins.  (Trillium, a monocot with net-veined leaves, is an exception).  Compare dicotyledons above.  Monocots were once thought to be more primitive that dicots, but now the monocots are believed to have arisen from the dicots. Their often apparent simplicity in structure is the result of evolutionary reduction (loss of a part which is no longer of any advantage to retain).
In this context, a species which has lived in a particular region for thousands of years, such that it has co-evolved with its associates (animals, other plants, fungi, and bacteria).  It is not enough for the plant to have reproduced in the area for a few generations unaided by human beings;  these latter are called naturalized, but not native.  See our essay "The Meaning of Native" on this website.
A species which has not lived in a particular region for thousands of years, but has immigrated from another region, usually within the past 250 years.  The words "alien" and "exotic" are synonyms.

In the catalog, non-native species will be specially marked, but this particular feature has not been added yet.

(Since we associate people, other animals, or plants from far away with a colorful, unusual, and often exciting strangeness, we have come to associate the word "exotic" with that strangeness.  In common usage, the word has lost the specific meaning of "from other lands" so that people will speak of the Arizona desert's "exotic cacti" because they look strange—even though they are native to the desert and by strict definition not exotic at all!)
A plant living for more than a few years.  Some perennials die back each year to a storage organ such as a bulb or corm (e.g. Calochortus, the sego lilies) while others retain green leaves year round.  Trees and shrubs are technically woody perennials, but in general usage (and in the catalog pages), the term perennial is restricted to non-woody perennials.
A plant with many woody stems, generally lower than or not extraordinarily higher than an adult human being or other large mammals.  Compare with tree, below.
species (sp.)
A species is a group of organisms sharing a closely related common gene pool because of frequent interbreeding.

This is not always (or even usually) easy to decide, for individual plants from different regions, which have clearly distinct traits, may have common relatives with traits intermediate between them.  Are such plants distinct species which occasionally hybridize, or do they belong in one all-encompassing "polymorphic" (many-formed) species?  Because of such ambiguities, some botanists would go so far as to say that the species concept is a human construct only approximately reflecting the reality of nature.

The word "species" is used both as a singular and a plural.  The abbreviation "sp." indicates the singular form, while "spp." is plural.  If I write Quercus sp., I'm writing about one species of oak which I don't happen to know the name of (or don't care to tell you!).  But when I write Quercus spp., I mean two or more species of oaks.

The species name of an organism includes both parts of the scientific name, the genus and the second, specific name.  For example, the genus of Gambel oak is Quercus, but the species of Gambel oak is Quercus gambelii.  The second name (gambelii) is called the specific name or epithet.  It is always printed in lower-case letters (though older manuals may use the system of capitalizing the specific name if it was named in honor of someone).
A perennial with a woody base only. Its bushy structure consists of non-woody stems, unlike a true shrub. Some species of perennials develop a woody base under favorable conditions only and can then be classified as subshrubs.
subspecies (ssp.)
When a species is made up of distinct, geographically separate groups which are yet not distinct enough to constitute separate species, the term subspecies is employed.  In the past, botanists would either not use the term or use it interchangeably with "variety."  More recently, a variety is usually considered to be less distinct than a subspecies.  Thus, just as a species can have several subspecies, a subspecies can have several varieties.  This practice is sometimes used in the USDA PLANTS online database, and here in NAZ Flora.

Be careful not to confuse the abbreviation "ssp." (subspecies) for "spp." (species, plural).  You can also find subspecies abbreviated as "subsp." in many recent works, an innovation which makes the ssp./spp. distinction less problematic.
A plant with one or only a few relatively thick woody stems (trunks) usually growing high above the reach of large mammals such as deer or human beings.  Compare with shrub, above.
variety (var.)
See above for the discussion.  The word in common parlance is loosely equivalent to "species," but this is not how the botanist uses the word.
vascular plant
Ah, so you are wondering what the heck a vascular plant is, as in Northern Ariozna Flora: A Photographic Annotated Catalog of Northern Arizona Vascular Plants?  This term refers to plants with a vascular conducting system, i.e. one with veins with which to transport fluids throughout the plant.  It includes just about all large land plants, including all trees and shrubs, all flowering plants, and all ferns.  Not included are plants such as mosses, which have no roots and absorb water through the membranes, nor does it include algae.
A plant with long stems (woody or not) which depends on other plants or surfaces for support.  Vines may get that support by means of tendrils, by twining around another object, by attaching themselves with aerial rootlets, or merely by sprawling over a more rigid plant, boulders, or the ground.
To a gardener, any plant which grows where it is not wanted.  To a rancher, any plant which is especially prolific and which usually has no evident use to cattle or other livestock (or is even poisonous for livestock to eat).  To the botanist, a plant which is especially adept at quickly colonizing areas disturbed by human beings or our livestock.  Most weeds, by this latter more objective definition, happen to be non-native.
Made up of, or having wood, such as a branch or trunk.

Glossary prepared by Lee Dittmann

This page last revised 9 April 2009.

Northern Arizona Flora
Ferns and Fern Allies Gymnosperms Angiosperms: Dicots Angiosperms: Monocots
Introduction Contributors Glossary References
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