Living Landscapes

GRASSES OF THE COLUMBIA BASIN OF BRITISH COLUMBIA
Heather Stewart, Richard Hebda
Table of Contents
Glossary

GLOSSARY

Alpine:
Those parts of mountains that rise above the elevational cold tolerance of trees.

Annual:
Complete the life-cycle (seed to seed) in one growing season.

Anther: The pollen-bearing part of the stamen.

Apical: Pertaining to the apex or tip of a plant organ.

Appressed: Pressed flat against or close to another organ, as flowerhead branches against the axis or hairs against a stem or leaf.

Arctic: Pertaining to the unforested regions that occur north of the tree line.

Ascending: Rising upward, as stems that curve upward from the base; or branches of an flowerhead that extend upward at an angle of about 40º-70º.

Auricles: Projecting lobes or appendages of leaf tissue, usually paired, and arising from the junction of the leaf sheath and the blade. Projecting on either side of the collar.

Awn: A bristle -- usually at the end of a glume, lemma or palea.

Axis: General term for a central, supporting grass organ e.g. a rachilla or in particular, the main or central stem of a compound flowerhead.

Basal: That part near to, or forming part of, the base. In grasses, leaves can be basal or along the stem.

Bearded: Long, often stiff, hairs at the base of the lemma. In some genera their presence is a key feature to identification.

Biennial: Growing for two years -- usually producing flowers and fruit in the second year

Bifid: Two-lobed or split at the apex.

Blade: Broad part of the leaf that extends from the stem.

Blue Listed: Vulnerable, rare taxa that could become candidates for the Red List in the forseeable future. A vulnerable species is of special concern because of characteristics that make it particularly sensitive to human activities or natural events.

Bract: Any of the reduced or modified leaves of the flowerhead and upper part of a shoot; in grasses, the glumes and lemmas are bracts.

Bunchgrass: A grass habit that produces a large number of side shoots. The current years leaf growth is usually basal and previous years sheaths can persist.

Caespitose: Growing in tufts i.e. with several or many stems growing closely together. Referred to as tufted in this treatment.

Callus: A hard projection that appears to be an extension of the lemma.

Callus-scar: Scar left on the thickened base of the lemma.

Caryopsis: The fruit of grasses; the grain.

Ciliate: With a fringe of hairs on the margin.

Clasping: Surrounding or holding tightly, as a type of auricle.

Collar: Junction area of the leaf sheath and blade.

Compressed: Unusually flattened in one plane as the spikelets of some grasses. The spikelet can be compressed across the back so that the glumes and lemma appear flattened (dorsal) or from the sides so that the spikelet or the glumes appears keeled (lateral).

Contracted: Closely bunched together as the flowerhead branches with the axis in some grasses.

Culm: The above-ground stem of a grass.

Deciduous: Part of the plant that falls away at the end of its normal function. Awns are sometimes deciduous.

Decumbent: With a horizontal or inclined base that curves upward into an erect or ascending tip; as in some grass stems.

Depauperate: Small or poorly developed; the condition of impoverished or dwarfed plants that are below average size.

Drooping: Bending or arching downward, especially as the tips of flowerhead branches weighted down by spikelets.

Endemic: Confined to a particular, often relatively small, geographic area.

Erect: Standing upright.

Fertile lemma: A lemma with a functional flower inside it, either male or female. If you find any parts inside the lemma at all you can consider it a fertile lemma. See also sterile lemma.

First glume: The lower glume (toward ground) usually smaller.

Flexuous: Having relatively firm bends.

Flower: The basic unit of a grass spikelet, having one flower subtended and usually enclosed by the lemma and the palea.

Geniculate: Abruptly and clearly bent or twisted.

Glume: One of a pair of bracts, found at the base of a grass spikelet.

Grass bald: An open area in an otherwise forested zone, and often in a mountainous region, in which grasses are a significant or dominant part of the vegetation; grass balds often occur in regions having summers with deficient precipitation, and are usually confined to areas of shallow soil (as on mountain summits occurring below the subalpine zone) and/or steep south-facing or west-facing slopes

Hairy: Bearing hairs (trichomes) of any sort.

Herbaceous: Herblike.

Hyaline: Thin and translucent or transparent.

Indurate: Hardened; firm; retaining its shape.

Internode: The part of a stem or culm between two successive nodes.

Introduced: Plant origins from outside North America and introduction is either accidental or intentional.

Involute/ Inrolled Rolled inwards, as the margins of a grass leaf blade, exposing the lower surface and concealing or partially concealing the upper surface.

Keeled: Having a conspicuous, central, longitudinal ridge (resembling the keel of a ship), as the lemma of some grasses.

Lanceolate: Lance-shaped, long and tapered to a point.

Lemma: The outer, usually larger (away from the axis) bract of the pair of bracts that enclose a grass flower. The inner bract is called the palea.

Ligule: In grasses, applied to the tongue-shaped appendage arising from the collar at the junction of the leaf sheath and blade, and partially surrounding the stem.

Montane: Pertaining to mountain slopes, and often, in particular, to the mostly forested zone extending downslope from the subalpine forest zone.

Native: The place of origin is North America. In the case of circumpolar or circumboreal species these are considered to be native in this treatment.

Nerve: A longitudinal vein of a leaf, lemma or other organ.

Nodding: Bent to the side, as is the tip of a grass flowerhead that is not erect.

Node: The part of a stem to which a leaf is attached; in grasses this is often a thickened part of the stem. This is the base of the sheath for the leaf above and where the measurement should be taken from for the amount of opening in the sheath.

Ovary: The structure that encloses the young, undeveloped seeds.

Palea: The inner (toward the axis) of the pair of bracts that enclose a grass flower.

Panicle: A compoundly branched flowerhead, as in many grasses.

Pedicel: The stalk of a single flower; in grasses, the stalk of a single spikelet.

Perennial: Growing for more than two growing seasons usually flowering each year.

Prow-shaped: Shaped as the forward part of a ship; said of some grass leaf blade tips that have their margins turned upward -- and sometimes inwards as well - resembling a ship's prow.

Pubescent: Having short, soft hairs; sometimes loosely used for bearing hairs (trichomes) of any sort i.e. hairy.

Rachilla: The axis of a spikelet.

Rachis: In grasses, the main or central stem of a simple (non-compound) flowerhead such as that of a spike (compare axis).

Red Listed: candidate for legal designation as an endangered or a threatened species. An endangered species is an indigenous species facing extinction in B.C. A threatened species is one that is likely to become extinct if limiting factors are not reversed.

Reflexed: Bent backward.

Rhizomatous: Having rhizomes.

Rhizomes: The underground stems of a plant or root stems; has roots and shoots at the nodes.

Second glume: The upper glume usually larger (towards the tip of the spikelet).

Sheath: The part of a grass leaf that wraps around the stem. It is important to distinguish the sheath from the stem: a hairy sheath, mistaken for a stem may mislead you in The key.

Spikelet: In grasses, the compact unit of the flowerhead consisting of one or two glumes at the base and one to several flowers borne on the spikelet axis.

Spreading: Directed outward; in grasses, often used to refer to hairs on an organ e.g. a leaf sheath, or to flowerhead branches that form an angle with the axis between that of upright and perpendicular i.e. between about 70º-90º.

Sterile lemma: A lemma with no functional flower or flower parts inside.

Stolon: Above-ground stems of a plant that produces roots and shoots at the nodes.

Subalpine: Pertaining to the forest zone immediately below the alpine zone.

Submontane: Pertaining to the steppe zone in mountainous areas occurring below the montane zone.

Throat: Variously the area between or the angle formed by the upper margins of the leaf sheath.

Truncate: As if cut off, having the apex or base of an organ transversely straight or nearly straight.

Alpine:	Those parts of mountains that rise above the elevational cold tolerance of trees.
Annual:	Complete the life-cycle (seed to seed) in one growing season.
Anther:	The pollen-bearing part of the stamen.
Apical:	Pertaining to the apex or tip of a plant organ.
Appressed:	Pressed flat against or close to another organ, as flowerhead branches against the axis or hairs against a stem or leaf.
Arctic:	Pertaining to the unforested regions that occur north of the tree line.
Ascending:	Rising upward, as stems that curve upward from the base; or branches of an flowerhead that extend upward at an angle of about 40º-70º.
Auricles:	Projecting lobes or appendages of leaf tissue, usually paired, and arising from the junction of the leaf sheath and the blade. Projecting on either side of the collar.
Awn:	A bristle -- usually at the end of a glume, lemma or palea.
Axis:	General term for a central, supporting grass organ e.g. a rachilla or in particular, the main or central stem of a compound flowerhead.
Basal:	That part near to, or forming part of, the base. In grasses, leaves can be basal or along the stem.
Bearded:	Long, often stiff, hairs at the base of the lemma. In some genera their presence is a key feature to identification.
Biennial:	Growing for two years -- usually producing flowers and fruit in the second year
Bifid:	Two-lobed or split at the apex.
Blade:	Broad part of the leaf that extends from the stem.
Blue Listed:	Vulnerable, rare taxa that could become candidates for the Red List in the forseeable future. A vulnerable species is of special concern because of characteristics that make it particularly sensitive to human activities or natural events.
Bract:	Any of the reduced or modified leaves of the flowerhead and upper part of a shoot; in grasses, the glumes and lemmas are bracts.
Bunchgrass:	A grass habit that produces a large number of side shoots. The current years leaf growth is usually basal and previous years sheaths can persist.
Caespitose:	Growing in tufts i.e. with several or many stems growing closely together. Referred to as tufted in this treatment.
Callus:	A hard projection that appears to be an extension of the lemma.
Callus-scar:	Scar left on the thickened base of the lemma.
Caryopsis:	The fruit of grasses; the grain.
Ciliate:	With a fringe of hairs on the margin.
Clasping:	Surrounding or holding tightly, as a type of auricle.
Collar:	Junction area of the leaf sheath and blade.
Compressed:	Unusually flattened in one plane as the spikelets of some grasses. The spikelet can be compressed across the back so that the glumes and lemma appear flattened (dorsal) or from the sides so that the spikelet or the glumes appears keeled (lateral).
Contracted:	Closely bunched together as the flowerhead branches with the axis in some grasses.
Culm:	The above-ground stem of a grass.
Deciduous:	Part of the plant that falls away at the end of its normal function. Awns are sometimes deciduous.
Decumbent:	With a horizontal or inclined base that curves upward into an erect or ascending tip; as in some grass stems.
Depauperate:	Small or poorly developed; the condition of impoverished or dwarfed plants that are below average size.
Drooping:	Bending or arching downward, especially as the tips of flowerhead branches weighted down by spikelets.
Endemic:	Confined to a particular, often relatively small, geographic area.
Erect:	Standing upright.
Fertile lemma:	A lemma with a functional flower inside it, either male or female. If you find any parts inside the lemma at all you can consider it a fertile lemma. See also sterile lemma.
First glume:	The lower glume (toward ground) usually smaller.
Flexuous:	Having relatively firm bends.
Flower:	The basic unit of a grass spikelet, having one flower subtended and usually enclosed by the lemma and the palea.
Geniculate:	Abruptly and clearly bent or twisted.
Glume:	One of a pair of bracts, found at the base of a grass spikelet.
Grass bald:	An open area in an otherwise forested zone, and often in a mountainous region, in which grasses are a significant or dominant part of the vegetation; grass balds often occur in regions having summers with deficient precipitation, and are usually confined to areas of shallow soil (as on mountain summits occurring below the subalpine zone) and/or steep south-facing or west-facing slopes
Hairy:	Bearing hairs (trichomes) of any sort.
Herbaceous:	Herblike.
Hyaline:	Thin and translucent or transparent.
Indurate:	Hardened; firm; retaining its shape.
Internode:	The part of a stem or culm between two successive nodes.
Introduced:	Plant origins from outside North America and introduction is either accidental or intentional.
Involute/ Inrolled	Rolled inwards, as the margins of a grass leaf blade, exposing the lower surface and concealing or partially concealing the upper surface.
Keeled:	Having a conspicuous, central, longitudinal ridge (resembling the keel of a ship), as the lemma of some grasses.
Lanceolate:	Lance-shaped, long and tapered to a point.
Lemma:	The outer, usually larger (away from the axis) bract of the pair of bracts that enclose a grass flower. The inner bract is called the palea.
Ligule:	In grasses, applied to the tongue-shaped appendage arising from the collar at the junction of the leaf sheath and blade, and partially surrounding the stem.
Montane:	Pertaining to mountain slopes, and often, in particular, to the mostly forested zone extending downslope from the subalpine forest zone.
Native:	The place of origin is North America. In the case of circumpolar or circumboreal species these are considered to be native in this treatment.
Nerve:	A longitudinal vein of a leaf, lemma or other organ.
Nodding:	Bent to the side, as is the tip of a grass flowerhead that is not erect.
Node:	The part of a stem to which a leaf is attached; in grasses this is often a thickened part of the stem. This is the base of the sheath for the leaf above and where the measurement should be taken from for the amount of opening in the sheath.
Ovary:	The structure that encloses the young, undeveloped seeds.
Palea:	The inner (toward the axis) of the pair of bracts that enclose a grass flower.
Panicle:	A compoundly branched flowerhead, as in many grasses.
Pedicel:	The stalk of a single flower; in grasses, the stalk of a single spikelet.
Perennial:	Growing for more than two growing seasons usually flowering each year.
Prow-shaped:	Shaped as the forward part of a ship; said of some grass leaf blade tips that have their margins turned upward -- and sometimes inwards as well - resembling a ship's prow.
Pubescent:	Having short, soft hairs; sometimes loosely used for bearing hairs (trichomes) of any sort i.e. hairy.
Rachilla:	The axis of a spikelet.
Rachis:	In grasses, the main or central stem of a simple (non-compound) flowerhead such as that of a spike (compare axis).
Red Listed:	candidate for legal designation as an endangered or a threatened species. An endangered species is an indigenous species facing extinction in B.C. A threatened species is one that is likely to become extinct if limiting factors are not reversed.
Reflexed:	Bent backward.
Rhizomatous:	Having rhizomes.
Rhizomes:	The underground stems of a plant or root stems; has roots and shoots at the nodes.
Second glume:	The upper glume usually larger (towards the tip of the spikelet).
Sheath:	The part of a grass leaf that wraps around the stem. It is important to distinguish the sheath from the stem: a hairy sheath, mistaken for a stem may mislead you in The key.
Spikelet:	In grasses, the compact unit of the flowerhead consisting of one or two glumes at the base and one to several flowers borne on the spikelet axis.
Spreading:	Directed outward; in grasses, often used to refer to hairs on an organ e.g. a leaf sheath, or to flowerhead branches that form an angle with the axis between that of upright and perpendicular i.e. between about 70º-90º.
Sterile lemma:	A lemma with no functional flower or flower parts inside.
Stolon:	Above-ground stems of a plant that produces roots and shoots at the nodes.
Subalpine:	Pertaining to the forest zone immediately below the alpine zone.
Submontane:	Pertaining to the steppe zone in mountainous areas occurring below the montane zone.
Throat:	Variously the area between or the angle formed by the upper margins of the leaf sheath.
Truncate:	As if cut off, having the apex or base of an organ transversely straight or nearly straight.


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