A special thanks to Ted Jordan Meredith for the use of this expansive glossary, taken from his book, Bamboo for Gardens, Timber Press, 2001. Available from Amazon.com

adventitious
Occurring from an unusual or unexpected location. In the context of bamboos, the root system is adventitious, in that the roots do not primarily arise from a primordial root, but rather at the nodes of rhizomes and culms. In Chusquea, branch buds are adventitious, in that they arise in multiples independent of the "normal" location.

aerial root
A root growing above ground level. Some bamboos have a tendency to produce aerial roots at their culm and branch nodes.

albino
All white, lacking chlorophyll. An albino seedling will grow for a time, nourished by the nutrients stored in the seed, but without any food producing mechanism, its demise is a certainty.

amphimorph
A rhizome system that includes both pachymorph and leptomorph rhizomes. Bamboos with amphimorph rhizome systems are rare. So far, amphimorph rhizome systems have been confirmed in only 3 species, the New World bamboos Aulonemia fulgor, Chusquea fendleri, and C. scandens. Cf. leptomorph and pachymorph.

amphipodial
At a time when the terms monopodial and sympodial were employed to describe two types of rhizomes distinguished by branching habit, the term amphipodial was promulgated to describe bamboos that had "monopodial rhizomes" but were also capable of generating new culms by tillering from the base of existing culms, in the manner of a sympodial system. The term itself, as originally conceived, suggested, incorrectly, that species, such as Shibataea kumasaca, with its "monopodial rhizomes" and tillering culms possessed both rhizome types. In the context of current and more precise terminology, S. kumasaca has a strictly leptomorph rhizome system. However, if the terms amphipodial, sympodial, and monopodial are applied more narrowly and authentically, referring only to branching habit, rather than to rhizome type, then the term amphipodial is both useful and valid. Some bamboos, such as S. kumasaca, have rhizome systems with monopodial branching, and tillering culms that exhibit sympodial branching. Since both branching patterns are present, the species can be said to have amphipodial branching. Cf. sympodial, monopodial, pachymorph, leptomorph, and amphimorph.

apical meristem
A group of actively dividing, undifferentiated cells, at the growing tip of a stem or root. In bamboos, the sheath is critical to the growth of the culm shoot and the rhizome. The sheath cells are the first to become differentiated at the growing tip.

arborescent
Having the form and characteristics of a tree. Treelike. The large, timber bamboos are arborescent.

auricle
The "ears" that extend from the upper part of a sheath on both sides of the blade. Depending on the species, they may be prominent or entirely lacking. Regardless of species, auricles are entirely absent from rhizome sheaths.

axis
A central stem along which, plant parts are arrayed.

bamboos
Grasses of the subfamily Bambusoideae. The woody species of the subfamily belong to the tribe Bambuseae. The herbaceous species belong to the tribe Olyreae.

blade
The part of the leaf that is typically flat and green, and is dedicated to photosynthetic activity. The blade may be prominent, reduced, modified, or absent. The blade is dominant on the foliage leaves of the bamboo plant, where the sheath is much smaller, and barely distinguishable from the stem. The foliage leaf blades are what we commonly think of as the "leaves" when we look at a bamboo plant. The blade is far less prominent on culm leaves, where the protective sheath dominates, and the blade is essentially absent, or no more than the hard-pointed tip, on the sheaths that protect the rhizome.

bract
A modified, protective leaf, such as those found within or just below the flowering parts of plants. In bamboo, the modified, sometimes scale-like leaves that protect the rhizomes, or those that protect new buds, may be called bracts.

branch complement
The branch or bud grouping at a node is called a complement. The number of branches in the complement and the nature of their array are identifying characteristics for bamboo. The branch complement most typical of a species is found at the middle of the culm. Lower branches are not always fully developed. Upper branches do not always maintain the branching pattern that distinguishes the species.

bud
A small, dormant protuberance on a stem or branch, from which a shoot, leaf, or flower may arise. In bamboo, the buds on rhizomes can produce a culm or other rhizomes. Buds on culms and branches can produce branches or leaves. Except for Chusquea and Apoclada, all branches emerge from a single primary bud, but may bear lateral buds so close to the primary bud that it appears many branches are emerging independently from the culm. In these instances, the internode of the primary bud is so compressed it is barely distinguishable from its base.

bud complement
See branch complement.

bulliform cells
Large cells in the epidermis of the leaf that collapse during water stress, causing the leaves to curl, or roll tightly into the shape of needles, thus reducing the leaf surface area to a minimum.

caespitose
Tightly grouped or clumped. Bamboos with short-necked, pachymorph rhizome systems have a caespitose habit. Cf. diffuse and pluricaespitose.

caryopsis
The characteristic "seed" of grasses, it is typically a hard, dry, one-seeded fruit that does not open. A cereal grain is a familiar example.

cilia
Small, fine hairs along the margin of a structure, usually forming a fringe.

clade
An evolutionary group or lineage descended from a common ancestor.

cladistics
An analytical methodology that focuses on the branching of lineages to determine evolutionary history, and on taxonomic groupings reflecting evolutionary lineage.

cladogram
A branching diagram depicting evolutionary lineages.

clumping
See caespitose.

coriaceous
Leathery and tough.

cotyledon
The seed leaf. It may remain within the seed coat, or emerge during germination and turn green. Monocots have a single seed leaf. Dicots have a pair of seed leaves.

culm
The aboveground stem of a grass plant. The term is commonly associated with bamboo. Relative to other grass plants, the culms of many bamboos are very large and woody.
culm leaf
The large, overlapping leaves that encase the emerging new culm, protecting it, and providing temporary support while it lignifies. The sheath portion of the culm leaf is far larger than the blade. In common terminology, and in some technical literature, the culm leaf is sometimes called the "culm sheath." Cf. foliage leaf.

culm sheath
See culm leaf.

deciduous
Shedding or falling away at a specific season or period of growth. Culm leaves, for example, may be deciduous or may be persistent. Cf. persistent.

dicot
Dicotyledon. A plant with a pair of cotyledons (seed leaves) in the seed. Dicots include trees and shrubs. Bamboos, like other grasses, are monocots. Cf. monocot.

diffuse
Widely spaced, culms arising singly rather than in groups. This habit is associated with "running bamboos." It is also commonly, and erroneously, associated solely with bamboos that have leptomorph rhizome systems. Bamboos with long-necked, pachymorph rhizome systems may also have a diffuse habit. Cf. caespitose and pluricaespitose.

extravaginal branching
New branches burst through the culm leaf, near its base. This type of branching is characteristic of some Chusquea bamboos. Cf. infravaginal branching, and intravaginal branching.

fimbriae
Also called oral setae, fimbriae are the bristly, fringe-like hairs that extend from the margins of the auricles. They may be either prominent or lacking depending on the species. Although usually associated with the auricles, fimbriae may be present even when the auricles are absent.

foliage leaf
The foliage leaves are responsible for nearly all of the bamboo plant's photosynthetic activity. To this end, the blade is the predominant part of the foliage leaf. The sheath is typically much smaller, and scarcely apparent on casual observation. Cf. culm leaf.

gregarious flowering
The simultaneous flowering of a given generation of bamboo. Many bamboos have lengthy periods between flowering, lasting decades, or sometimes, more than a century. Flowering is termed gregarious when most or all of the same bamboo generation begin flowering. The bamboo plants are severely weakened, and often die. Many bamboos with leptomorph rhizome systems live and regain vigor after several years of weakness and struggle. Most bamboos with pachymorph rhizome systems die, relying on their seed to continue the species.

herbaceous
Not woody. Having no persistent aerial parts. Virtually all of our familiar bamboos are woody, but many, less well-known, bamboo species are herbaceous. Cf. woody.

infravaginal branching
Similar to extravaginal branching, except that the branches emerge horizontally or downward, breaking through at the base of the culm leaf sheath where it attaches to the culm. This type of branching is known only in the New World in some Chusquea species, and in the Old World in Dinochloa and Nastus. Cf. extravaginal branching, and intravaginal branching.

inflorescence
A flower cluster. Inflorescences have distinctive characteristics, and in spite of other taxonomic tools that are now available, continue to play an important role in bamboo taxonomy.

internode
The part of the culm that is between two nodes.

intravaginal branching
New branches emerge through the mouth of the culm leaf, rather than bursting through it. The emerging branches push the culm leaf away from the culm, if the culm leaf has not already shed. This type of branching is characteristic of many bamboos, including Phyllostachys. Cf. extravaginal branching, and infravaginal branching.

in vitro
Literally, in glass. A culture vessel or plate is used to reproduce various biological processes. In the context of bamboo, in vitro techniques are used to induce and study flowering, and for experimental and commercial propagation of bamboos.

lanceolate
Shaped like the head of a lance. Much longer than wide, tapering at both ends.

leaf
The primary photosynthetic organ. Most, but not all, leaves have a photosynthetic function. In the context of bamboos and other grasses, the sheath and blade are the primary parts of the leaf. All bamboos and other grasses have foliage leaves. Woody bamboos have culm leaves as well---their primary function being protection of the culm with large, overlapping sheaths, rather than photosynthesis. In common terminology, and in some technical literature, the culm leaf is sometimes called the "culm sheath." See culm leaf and foliage leaf.

leptomorph
A type of rhizome. Although a leptomorph rhizome can turn upward and become a culm, it most typically runs laterally without becoming a culm. A leptomorph rhizome is usually hollow and smaller in diameter than the culms that originate from it. The rhizome neck is always short. Internodes are longer than wide. Nodes are sometimes prominent. Buds are arranged horizontally. Most buds remain dormant, but those that germinate may produce either culms or new rhizomes. Bamboo species with leptomorph rhizome systems are associated with "running bamboos." Cf. pachymorph and amphimorph.

ligule
The "little tongue" behind sheath blade extends upward from the tip of the sheath proper. Depending on the species, the ligule ranges from prominent to inconspicuous. The ligule helps keep moisture away from the newly forming culms and branches, and prevents moisture from running down the culm or branch and collecting at the node. The woody bamboos, unlike herbaceous bamboos, also have an outer ligule, but it is always much smaller, and is usually nearly invisible.

lodicules
Small, scale-like flaps at the base of grass flowers, thought to be vestiges of petals or sepals.

micropropagation
Cells from various parts of a plant can be cultured in a specialized medium. Nutrients and hormones are manipulated so that the test tube grown cultures differentiate into roots and shoots, and ultimately a complete plant that can be grown in soil.

monocarpic
Flowering once, and then dying. Monocarpy is widespread among woody bamboos. Most pachymorph bamboos that are subject to gregarious flowering are monocarpic. As a group, leptomorph bamboos are more likely to survive gregarious flowering, but are typically severely weakened, and monocarpy occurs with some frequency as well.

monocot
Monocotyledon. A plant with only a single cotyledon (seed leaf) in the seed. Bamboos, like other grasses, are monocots, as are lilies, orchids, palms, and so forth. Cf. dicot.

monophyletic
A group of taxa that all descend from a common ancestor. Cf. polyphyletic.

monopodial
A term originally derived to describe a rhizome branching habit. In monopodial branching, a single, dominant stem, or axis, gives rise to secondary branches, or axes. In the context of rhizomes, each rhizome runs laterally, usually without turning upward to become a culm. This rhizome gives rise to secondary axes which either turn upward to become culms, or which constitute new, laterally running rhizomes that will, in turn, give rise to secondary axes of their own. Although describing only the branching habit, exclusive of other structural characteristics, the term is loosely synonymous with leptomorph when applied to rhizomes---at least, one frequently encounters it as such in the literature. Cf. sympodial and amphipodial.

montane
Of, or growing in, mountainous areas.

morphology
Study of the form and structure of organisms, as opposed to the study of their functions.

multicaespitose
See pluricaespitose.

neck
Usually associated with the rhizome, the neck is a structural element of every segmented axis of the bamboo plant, including the culm and branches, as well as the rhizome. On the neck, the nodes have no buds, and the sheaths are small and scalelike. Structurally, the neck permits creation of a new and larger axis. The highly compressed stacking of progressively larger internodes can create a new axis much larger than the axis from which it originated. This is well illustrated by the rhizomes and culms of leptomorph timber bamboos. The rhizomes are proportionally much smaller in diameter than the culms (new axes) they generate. The highly compressed internodes of the neck progressively increase in diameter to form the base of the culm.

nectary
A gland associated with flowers. Nectaries secrete nectar to attract insects. Most bamboos are wind pollinated, and the flowers have no nectaries.

nodal diaphragm
In most bamboos, the internodes are hollow. Only the nodes are solid, forming the nodal diaphragm. All the cells along the internodes are axially oriented, that is, they run along the length of the internode, and are devoid of radial cell elements. Only at the nodes do the cells turn inward across the nodal diaphragm.

node
The place on a culm, branch, or other axis where leaves, shoots, branches, roots, or flowers are attached. In the context of bamboo, the nodes delimit the segments of the segmented structure.

oral setae
See fimbriae

pachymorph
A type of rhizome. A pachymorph rhizome always turns upward and becomes a culm. It is nearly always curved, and, at its maximum width, is slightly thicker than the above ground culm it becomes. Rhizome nodes are not prominent. The internodes are wider than long, and usually solid. New rhizomes emerge from lateral buds on an existing rhizome. As with the original rhizome, these new rhizomes always turn upward and become culms. The neck of the rhizome can be either long or short. This structure is associated with "clumping bamboos," although many species with pachymorph rhizome systems do not exhibit a clumping habit. Cf. leptomorph and amphimorph.

palmate
Three or more leaves or leaflets originating from an apparent common point, in the manner of a palm.

persistent
Not deciduous. Not shedding or falling away. Culm leaves, for example, may be persistent or may be deciduous. Cf. deciduous.

phylogeny
The evolutionary history of a species or other, higher, taxonomic grouping.

pluricaespitose
Arising in dispersed clumps. Some species with pachymorph rhizome systems that have a combination of short and long rhizome necks display this culm and clump habit. Some species with leptomorph rhizome systems and tillering culms also display this habit. For the leptomorph bamboos, this habit is sometimes termed amphipodial, or (incorrectly) amphimorph. Cf. caespitose and diffuse.

polyphyletic
A group of taxa that do not all descend from a common ancestor. Cf. monophyletic.

primordium
The earliest stage of development, or the most rudimentary form of an organism or plant part.

pruinose
A white, waxy, powdery coating. In the context of bamboos, for example, the young culms of some species are pruinose.

pseudopetiole
Similar to the petiole in dicots, it is the elongated constriction at the base of the foliage leaf blade in bamboos and a few other grasses. Although the pseudopetiole is attached to the sheath, rather than directly to a branch, the sheath is so tightly wrapped around the branch that it is barely distinguishable from it. As a result, the foliage leaves give the conventional appearance of "leaves on stems, connected to branches," resembling familiar trees and shrubs in that regard.

pubescent
Covered with short, fine hairs.

rhizome
The underground stem, or underground portion of a stem. The rhizome has the same or similar structure as the culm, the aboveground stem. It has nodes, internodes, leaves (here generally consisting of the sheath with no blade), and roots. Although roots are a prominent feature of the rhizome, in some species, roots or root primordia appear on nodes of aboveground stems as well.

root
The (usually) underground part of a plant that absorbs water and nutrients. It also serves to anchor the plant in the soil. It is the only bamboo axis that does not have a segmented structure---that is, unlike culms, branches, and rhizomes, roots have no nodes, internodes, or sheaths.

running
See diffuse and pluricaespitose.

scandent
Climbing.

sheath
The lower part of the leaf that tightly encircles the stem or branch. It is a very large and prominent part of the culm leaf, but a much smaller, and sometimes barely noticeable, part of the foliage leaf.

sheath scar
Circling the lowermost part of the node, it is the scar or mark left where the sheath was attached to the node.

sport
A plant that is markedly different from the parent plant, generally as the result of a mutation.

spikelet
The basic unit of a grass flower cluster.

sulcus
A pronounced groove running the length of the internode, presumably caused by the presence of a developing branch bud at the internode's base, grooving the culm as the internode elongates. A prominent sulcus is a distinguishing characteristic of Phyllostachys.

supranodal ridge
The uppermost part of the node. Varying among species, the supranodal ridge ranges from nearly indistinguishable to very prominent.

sympodial
A term originally derived to describe a rhizome branching habit. In sympodial branching, each succeeding branch, or axis, becomes dominant. In the context of rhizomes, each new rhizome turns upward and becomes a culm. Although describing only the branching habit, exclusive of other structural characteristics, the term is loosely synonymous with pachymorph when applied to rhizomes---at least, one frequently encounters it as such in the literature. Cf. monopodial and amphipodial.

taxon
A taxonomic category or group (pl. taxa).

tessellation
In the context of bamboos, it is the fine cross veining in the leaves that creates a grid-like or checkered appearance that is visible on close examination. Not all bamboo leaves are tessellated. Tessellation is associated with a greater degree of cold hardiness. Most or all tropical bamboos have no leaf tessellation.

thorn
A stiff, woody, modified branch that ends in a sharp point. Some tropical and semitropical bamboo species have thorns.

tillering
Sending forth new shoots from the base of a stem. In the context of bamboos, new culms arise from the basal buds of existing culms without an intervening rhizome. It is characteristic of some bamboo species with leptomorph rhizome systems. Although sometimes superficially similar, bamboos with pachymorph rhizome systems have an intervening (though unified) rhizome between the existing stem and a new culm, and thus do not tiller, per se.

unicaespitose
See caespitose.

vascular bundle
Strands of conducting tissue. They are the means by which water, nutrients, and other substances are transported throughout the plant.

whip
In the context of bamboo, a culm generated from a whipshoot. See whipshoot.

whipshoot
For bamboos with leptomorph rhizome systems, the tip of a leptomorph rhizome may turn upward and grow into an aboveground culm. This occurs infrequently, but more often with recently established plants. Whips, the culms generated from whipshoots, tend to be smaller, more curved, less erect, and have shorter internodes than culms emerging from buds on a rhizome.

woody
Bamboo does not have true wood, which is derived from secondary growth. In this context, woody means lignified, and not herbaceous. Having persistent aerial parts. Virtually all of our familiar bamboos are woody, but many, less well-known bamboo species are herbaceous. Cf. herbaceous.