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GRASSES
OF THE COLUMBIA BASIN OF BRITISH COLUMBIA
The word Agrostis is Greek for grass, and the prefix calamos means reed. This genus, though reedy in appearance, is used as native forage grass in the west, especially in the montane and more northerly areas. In low wetland areas Calamagrostis canadensis provides wild, palatable hay for cattle, but the abundance is sporadic at best. All Calamagrostis species are perennial and relatively tall, with creeping rhizomes and a callus with a long, straight tuft of hairs, sometimes as long as the lemma. The spikelets are one-flowered and both glumes are equal and sharp-pointed. All species have awns on the lemma. The important feature in determining species differences is whether the lemma awns project beyond the glume tips or just reach the glume tips. It is also important to note whether the awns are twisted and bent or straight. Whether the flowerhead is open or is pressed close to the stem is also a useful distinguishing feature. The length of the callus hairs relative to the length of the lemma helps distinguish the species as well.
Leaves and Stem: The smooth to rough sheaths are open to the node and there are usually three to eight nodes along the stem. There are no auricles and the membranelike ligules are 3-8 mm long. The flat leaf blades are lax, rough on both surfaces and 3-8 mm wide. Flowerhead and Flowers: The open flowerhead can appear drooping when fully mature and is 5-30 cm long. The spikelets are numerous on the upper half of the branches. The glumes are slightly unequal, 3.0-4.5 mm long and can be slightly purple-tinged. The edges of the glumes feel rough, and the tips are sharp-pointed, the glumes are longer than the lemma. The lemma is almost transparent along the edges, and has a delicate awn extending just to the length of the lemma or slightly beyond. The callus has hairs from 1/2 to the length to the same length as the lemma, which is in contrast to the long cobwebby hairs of species in Poa. Similar Species: Bluejoint in British Columbia is divided into two intergrading varieties: canadensis and langsdorfii. Variety canadensis is a smaller plant, has shorter glumes than var. langsdorfii, and the keels of the glumes are not hairy. In addition, the margins of the lemmas are transparent and the awns of the lemma are thin and narrow and not obvious, whereas the lemma awns of var. langsdorfii are thicker and obvious.
Leaves and Stem: The smooth sheath is open and there is no auricle. The stem is rough just below the flowerhead but gets smooth toward the base. The pointed ligule is 3-5 mm high and has a ragged to hairy edge. The leaves are mostly basal, stiff, inrolled, 3 mm wide and blue-green. Flowerhead and Flowers: The branches of the 3-10-cm-long flowerhead are pressed close to the stem even when mature. This character may be misleading in dried specimens because the branches tend to spread when they are pressed. There are two transparent glumes with a raised keel that has a rough feel. The glumes are about equal in length and longer than the first flower. The lemma is slightly shorter than the glumes and has blunt teeth at the tip. The coarse, bent awn equals the glume and begins about 1 mm from the base of the lemma. Scattered hairs, half as long as the lemma, cover the callus. Similar Species: Plains Reedgrass could be confused with Pinegrass (Calamagrostis rubescens), but Plains Reedgrass is shorter (30 cm compared to 50-110 cm), does not have awns that protrude beyond the glume tips and the leaf collars do not have the tufted hairs of Pinegrass. This species is Blue Listed in Douglas et al. (1998), and is rare in British Columbia.
Leaves and Stem: Open sheaths are smooth to rough to the touch. The ligule stands 2-4 mm high, and is blunt with ragged edges. The sides of the ligule are often higher than the back. The leaves are 2-5 mm wide, shiny and flat when young, but become inrolled with age. The leaf edges are rough. Flowerhead and Flowers: The flowerhead is purple-to-bronze-tinged and grows to 4-10 cm long. Its branches are arranged close to the axis but not spreading. The glumes are slightly unequal and rough along the raised keel. The glumes exceed the first flower. The thin lemma is two thirds as long as the glume. A coarse, bent awn is attached near the base of the lemma and protudes beyond the lemma and the glume. The callus hairs are much shorter than the lemma. Similar Species: Purple Reedgrass belongs to the group of reedgrass that have twisted or bent awns protruding beyond the glume tips. Pinegrass (Calamagrostis rubescens) has this character too, but the flowerhead of Purple Reedgrass is denser than that of Pinegrass.
Leaves and Stem: Open and smooth sheaths have stiff hairs around the collars where the leaf blades meet the sheaths and the collars are covered in dense, short hairs. There are no auricles. Blunt ligules are 1-5 mm long and have a ragged edge. The flat leaves are 2-4 mm wide and rough at least along the edges. Flowerhead and Flowers: The flowerhead varies from slightly open to tightly closed. The nearly equal glumes are sharply pointed and nearly smooth, except along the raised keel where there are scattered, short, stiff hairs. The papery lemma is shorter than the glumes and thin. A bent and twisted awn arises just above the base of the lemma and equals the glumes. The callus has short hairs barely over 1 mm long. Similar Species: Pinegrass resembles Purple Reedgrass in that both have long lemma awns that protrude beyond the glumes and both have hairy collars. Purple Reedgrass has longer glumes (4-5 mm compared to 4.5-8 mm) than Pinegrass and the awns protrude further.
Leaves and Stem: The open sheath is smooth and has no auricles. Ligules that are 1-3 mm long and smooth edged. The 2-5 mm wide leaves are rolled inwards and feel smooth to rough. Flowerhead and Flowers: The flowerhead of stricta is a narrow spike. The flowerhead of ssp. inexpansa is a narrow pyramid. The flowerhead ranges from 5-12 cm long for both ssp. Glumes are purplish, bronze or greenish, and smooth to rough along the raised keel. Glumes are equal and about the same length as the first flower. The lemma has a long, straight awn attached below the middle and extending to equal the glumes. The callus hairs are unequal and 1/2 to 3/4 as long as the lemma. Similar Species: Subspecies inexpansa differs from ssp. stricta by its taller and more robust growth. The leaf blades of ssp. stricta are stiffer. The awn of the lemma usually extends slightly beyond the tip of the glume in ssp. inexpansa.
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