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GRASSES
OF THE COLUMBIA BASIN OF BRITISH COLUMBIA
Bromes all have small teeth at the tip of the lemma (apical teeth), and Douglas et al. (1994) use the size of these apical teeth as a critical character to make the distinction between annuals and perennials. Annuals have long, obvious teeth at the end of the lemma, but in perennials you have to search for these carefully. Often, especially in mature specimens, the teeth are located on the inside face of the robust awn. If you are following an identification key and you miss these, you will mistakenly follow the key into the genus Festuca. The teeth in some species of Bromus, such as Bromus pacificus may be so small that a dissecting microscope is required to see them clearly. Do not depend on the presence of the teeth as a sole character in determining whether a grass is a brome -- observe the other characters as well. There is one Festuca found in the Columbia Basin region, Festuca subuliflora, that has a forked tip on the lemma. Bromus spikelets have two very noticeable and distinct forms: one form has a very compressed or flattened appearance with a prominent keel along the ridge (back) of the lemma; and the other form does not have this keel and appears to have a rounded shape across the back of the lemma. To check these, take a lemma and cut across it. Keeled lemmas appear folded along the back, rounded lemmas are not. The spread of the flowerhead also divides the bromes into two types. Some flowerheads appear to be open, spreading away from the stem with long branches that droop. The other group has a flowerhead that appears close to the stem and appressed, with very short, upright branches. Finally, Bromus seems to have three groupings according to height. Tall bromes are 50-180 cm, medium bromes are 40-120 cm and short bromes are 5-90 cm. Height really depends on site characteristics, so if the site is poor, size will be shorter. For example, a Bromus sitchensis on a marginal site may be less than 50 cm tall. Pavlick's (1995) treatment of Bromus is the most recent and comprehensive in North America.
Leaves and Stem: The leaf sheaths are hairless to moderately hairy with short hairs that are slanted backwards toward the base of the sheath. The lower portions of the nodes are hairy. There are rarely any auricles, and if they are visible they are very small. The ligule is 3.5-5 mm high. Flowerhead and Flowers: The flowerhead is 10-28 cm long and erect, but can have spreading, not drooping, branches. The spikelets are 2-4 cm long and appear flattened. The lemma is keeled with a prominent nerve up the centre. Usually there are four to eight flowers per spikelets. One glume is two or more times longer than the other, and both glumes are much shorter than the first flower. The lemma is softly hairy with a wide, almost transparent or translucent (hyaline) margin. The awn is 3-10 mm long and straight. Similar Species: This species is very similar to Alaska Brome (Bromus sitchensis). In Douglas et al. (1994), Aleut Brome is considered to be the same as Alaska Brome. Pavlick (1995) describes Alaska Brome as having longer branches at the base of the flowerhead (>10 cm) and with an angle of branching greater that 90°.
Leaves and Stem: The leaf sheaths are hairless to hairy with long soft hairs. The nodes are hairy to hairless. There may or may not be auricles. The ligules are 1 mm long and blunt (squared). The 3-5-mm-wide leaf blades have various amounts of hairiness. Flowerhead and Flowers: The panicle is 10-20 cm long and open. The glumes are hairy, and the lemmas are hairy across the back and along the margins. This 7-11 flowered spikelet is not compressed and the lemma is rounded across the back. The first glume is much longer than the second glume, which is scarcely 1-3 mm long. Both are shorter than the first flower. The teeth at the tip of the lemma are tiny, so they are easy to miss on this species. The awn is 1-3 mm long. Similar Species: Nodding Brome can initially be confused with Fringed Brome (Bromus ciliatus), especially because of the hairs along the margin of the lemma and the open flowerhead in both species -- but Fringed Brome has no hairiness on the back of the lemma.
Leaves and Stem: The leaf sheaths are softly hairy and closed nearly to the top. The leaf blades are 2-5 mm wide and hairy on both sides. The ligules are .5-2 mm long, and have a rough edge or hairs along the edge. There are no auricles. Flowerhead and Flowers: The flowerhead has long branches with one spikelet at the end of each branch. The spikelets are approximately 15-27 mm long. One glume is almost half the size of the other and both are shorter than the first flower. The lemma is smooth or has a slightly bumpy feeling. The margin of the lemma forms a wide angle from the lemma tip to midway along the lemma and has a wide transparent (hyaline) margin. If there are awns, they are <.8 mm. Similar Species: The flowerhead of Rattlesnake Chess has a unique look and does not resemble any of our native species. It looks like an ornamental grass, and the stylized shape is perfect for flower arrangements.
Leaves and Stem: The soft hairy, to smooth sheaths are closed nearly to the top. The thick, tough, flat leaf blades are generally 3-6 mm wide (range 2-15 mm) and 10-30 cm long. The ligule is 2-3 mm long with a tattered edge. Small auricles may be present, but are difficult to see without a hand lens. Flowerhead and Flowers: The loose, open flowerhead ranges from 15-40 cm long. The ascending to drooping branches of the flowerhead usually end with several spikelets. The large very flattened spikelets are 2-4 cm long and have 7+ flowers. The two glumes are slightly unequal in length and much shorter than the spikelet. The lemmas are 12-20 mm long, keeled on the back and have two tiny teeth at the tip. A 6-15-mm-long awn projects between the two teeth of the lemma. Similar Species: California Brome closely resembles Alaska Brome (Bromus sitchensis). Alaska Brome has a more spreading and drooping appearance than California Brome. Alaska Brome has no auricles whereas California Brome does, though they may be minute. Spikelets of California Brome occur nearly to the base of the flowerhead, whereas in Alaska Brome they spread out toward the tips. The leaf blades of Alaska Brome are mostly greater than 10 mm wide, whereas they are mostly less than 10 mm in California Brome. California Brome intergrades with Mountain Brome (Bromus marginatus), and many authors consider them to be the same species. Mountain Brome has wider leaf blades (6-12 mm), and the flowerhead has erect and ascending lower branches compared to California Brome, which has drooping branches.
Leaves and Stem: The sheaths are hairless, but sometimes may have short backward-facing hairs. The nodes are hairy, but sometimes the lower nodes may be smooth. Leaf blades are 4-10 mm wide with scattered hairs on both surfaces or just on the upper surface. There are no auricles. Flowerhead and Flowers: The flowerhead is 15-25 cm long with long ascending-to-drooping open branches. The first glume is slightly shorter than the second, and both are much shorter than the first flower. The lemma of this species has obvious hairs along the margin of the lower half but is smooth across the back. This character can be observed with a good hand lens and is visible without dissection. Similar Species: Richardson Brome (Bromus richardsonii) is similar to Fringed Brome in that it has hairs on the margin of the lemma, but in the lower flower of the panicle, the back of the lemma is glabrous, whereas the lemma of Fringed Brome is scabrous across the back.
Leaves and Stem: The leaf sheaths are closed nearly to the top and are densely hairy, with backward-facing hairs. There is dense hairiness at and just below the nodes. The ligule is 1-2.5 cm long. The flat leaf blades are 2-5 mm wide and have long straight hairs on both sides. There are no auricles. Flowerhead and Flowers: The flowerhead is 7-16 cm long, open and spreading. The unequal glumes are shorter than the first flowers. The spikelets are flattened. The hardened or leathery lemmas have veins but not raised ridges, and they feel rough to the touch along the margins. The awn is 3-10 mm long and appears hairlike. Similar Species: Meadow Brome resembles European Smooth Brome (Bromus racemosus), which has not been collected in the Columbia Basin region. Pavlick (1995) mentions that European Smooth Brome may be a poorly developed form of Meadow Brome.
Leaves and Stem: Lower leaf sheaths appear densely to softly hairy, whereas the upper ones are less hairy. The short ligule is 1-1.5 mm high and hairy. Leaf blades are hairy on the upper side or both sides. There are no auricles. Flowerhead and flowers: The flowerhead is erect and the pedicels are pressed against the main stem. The pedicels are sometimes shorter than the spikelets, and therefore it appears as if there are no branches. The glumes are short-hairy to hairless. One glume is slightly shorter than the other and both are shorter than the first flower. The papery lemma has raised ridges on the back with short hairs or without hairs. These prominent ridges are an important feature in distinguishing Lopgrass from Meadow Brome. The edge of the lemma is bluntly angled from the tip to midway along the spikelet and has a wide hyaline (transparent) margin. The 6-8-mm-long awns are flattened at the base. These awns can be slightly curved outward but are not, strictly speaking, reflexed or bent. Similar Species: Lopgrass is also called Bromus mollis. Lopgrass has been said to intergrade with Meadow Brome, but the short, spikelike flowerhead differentiates it from Meadow Brome.
Leaves and Stem: The mostly smooth stems have erect or somewhat spreading branches at the base. The sheaths are mostly smooth and closed nearly to the top. Leaf blades are flat, 5 mm wide, usually drooping. The ligule is 3 mm high. If auricles are present, they are <0.5 mm, so a hand lens is required to see them. Flowerhead and Flowers: The narrowed to somewhat open-branched flowerhead is 10-20 cm long. Branches are ascending to spreading. The two unequal glumes are much smaller than the spikelet. The lemma has either no awn or a very short one (< 3 mm). The back of the lemma is rounded and not keeled. Similar Species: Many authors consider Smooth Brome and Pumpelly Brome (Bromus pumpellianus) to be similar species. Pavlick (1995) considers them two separate species, distinguished by a hairy lemma in Pumpelly Brome. Both species intergrade and are fully interfertile, but we will treat them separately in this paper. Smooth Brome resembles Alaska Brome (Bromus sitchensis) and California Brome. The spikelets of Smooth Brome are not flattened like those of California Brome, because the backs of the lemmas are rounded, not keeled.
Leaves and Stem: Leaf sheaths are soft hairy to densely hairy. The ligules are 1-2.2 mm long and are hairy or lacerate along the edges. Auricles are lacking. The softly hairy leaf blades are 1.5-3 mm wide. Flowerhead and Flowers: The flowerhead is 10-22 cm long and the branches are spreading, sometimes nodding or drooping, and somewhat slender. The glumes are hairless to slightly rough. Glumes are shorter than the first flower and one glume is about 2/3 the size of the other. The lemmas are almost leathery in texture and have seven to nine nerves. The awn is very noticeable, 8-13 mm long, often twisted, flattened at the base and angled away from the back of the lemma. This awn arises a short distance from the tip of the lemma, and almost appears reflexed. Similar Species: Japanese Chess can look different, depending on the stage of maturity. When immature, the awns do not diverge but appear to be straight. The very hairy leaves and the sheaths are a good way to distinguish Japanese Chess in the field.
Leaves and Stem: The leaf sheaths are sparsely to densely hairly with dense hairs around the throat. The ligule is 2-3.5 mm long, and appears to be gnawed or sparsely hairy along the edge. The leaf blades are flat and 6-12 mm wide. The leaves can be hairy to hairless. There are no auricles. Flowerhead and Flowers: The flowerhead is mostly narrow and 10-30 cm long, with erect branches. The spikelets appear compressed and large with six to nine flowers. The lemmas are leathery with seven to nine distinct nerves. The keeled lemmas are hairy along the margins and back, or only hairy on the margins and smooth on the back. The awns are 4-7 mm long. Similar Species: Mountain Brome resembles California Brome, and is considered by Douglas et al. (1994) to be synonymous. Pavlick (1995) distinguishes California Brome from Mountain Brome by the amount of spreading on the lower branches of the flowerhead. California Brome appears more spreading on the lower branches. See description for California Brome (Bromus carinatus).
Leaves and Stem: The nodes are densely hairy to lightly hairy and even sometimes hairless. There are short auricles on the lower leaves but these may be missing on the upper leaves. The leaves are flat and leaf sheaths have soft long hairs and the ligules are 3 mm long. Flowerhead and Flowers: The flowerhead is 10-20 cm long and stands erect or nods slightly. The erect branches are longer than the spikelets. The lemmas are hairy along the margins and are silky-hairy across the back; but the glumes are hairless, so the overall appearance is one of having no hairs because the glumes almost cover the lower lemma. Glumes are shorter than the first flower. The awn is less than 6 mm long and in many cases is not visible. In this species it is difficult to see the two tiny teeth at the tip of the lemma. Similar Species: Pumpelly Brome is considered by some authors to be the same as Smooth Brome. Pumpelly Brome ranges from the Arctic southward along the Cordillera to Colorado. Specimens of Pumpelly Brome may superficially appear to be a smooth brome such as Smooth Brome, except that its lemmas are hairy.
Leaves and Stem: Leaf sheaths are variously finely hairy to hairless, but often tufted hairy at the ligule. The ligules are 0.4-2 mm long and appear to be hairy or gnawed. The flat leaf blades are 3-12 mm wide and hairless. There are no auricles. Flowerhead and Flowers: The open, slightly nodding flowerhead is 10-25 cm long, with slender branches that spread or droop. One glume is about 2/3 the length of the other, and both are shorter than the first flower. The glumes are hairless and often have a small toothlike point at the tip. The lemmas are more or less covered in long straight hairs on the lower half of the margins. The lower spikelets may also be hairless on the back. The uppermost spikelets have short, appressed hairs. The awn is 2-5 mm long. Similar Species: Hitchcock et al. (1969) considered Richardson Brome to be similar toFringed Brome, but Pavlick (1995) distinguishes the two species by the fact that the culm nodes of Richardson brome are mostly hairless and the leaf sheaths often have tufts of long straight hairs. Fringed Brome has hairy nodes (although sometimes the lower nodes are smooth), and the leaf sheaths are mostly hairless, but sometimes with short backward-facing hairs.
Leaves and Stem: The leaf sheaths are hairless or covered by long scattered hairs. The sheaths are closed nearly to the top. There are no auricles. The ligules are 3-4 mm long with a ragged to hairy margin. The flat leaves are 8-15 mm broad and sparsely hairy with long hairs on the upper or both sides. Flowerhead and Flowers: The flowerhead in Sitka Brome is very open and 10-35 cm long. The pedicles or stalklets spread and droop somewhat. Strongly flattened spikelets often hang from the ends of the branches. The first glume is about 1/2 to 2/3 the length of the other, and both are much shorter than the first flower. Keeled lemmas bear 5-12-mm-long awns, have seven to nine nerves and scattered hairs cover the back. Similar Species: Sitka Brome closely resembles Aleut Brome and is considered to be the same species. Douglas (1994) separates Sitka Brome from California Brome based on the degree of panicle spreading and whether auricles are present. Sitka Brome has spreading panicle branches and no auricles. California Brome has tiny auricles and a spreading to drooping flowerhead.
Leaves and Stem: The sheaths are softly hairy, though those of the upper leaves sometimes are hairless. The leaves are flat, 2-4 mm wide and softly hairy on both leaf surfaces. Ligules are 2-3 mm long with a lacerate margin. There are no auricles. Flowerhead and Flowers: The flowerhead is 5-20 cm long and more or less lax. The branches are flexuous and the spikelets are often purplish. The first glume is 1/2 to 2/3 the length of the second glume, and both are much shorter than the first flower. The lemmas are hairy to long-hairy over the back and often with a few longer hairs on the margins. The spikelet appears to be brushlike, and the various awns tend to terminate at the same level. The 10-18-mm-long awns appear longer than the spikelet. Similar Species: Cheatgrass is distinct from most of the other species in the Columbia Basin region.
Leaves and Stem: The long, slender stems have few leaves along the culm and often droop. The leaf sheaths are hairy to smooth, and the culm nodes are hairy. The flat, lax leaf blades are hairy on at least one surface, and are up to 14 mm wide. The ligules are 2-6 mm long, blunt and gnawed looking. There are no auricles. Flowerhead and Flowers: The open, narrow, drooping flowerhead has slender branches with few-flowered spikelets and is 10-15 cm long. The first glume is about 1/2 the length of the second, both being much shorter than the first flower. The lemmas are 8-15 mm long and coarsely-hairy on the the margins. The awn is 6-12 mm long and arises at the tip. Similar Species: The relatively small, few-flowered, drooping flowerheads with rounded spikelets are distinct features of Columbia Brome. Smooth Brome is like Columbia Brome, but it has fat spikelets and the awns are much shorter. Smooth Brome is also like Columbia Brome, but it has rhizomes rather than tufted roots.
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