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blue bunchgrass, blue fescue, bluebunch fescue, Idaho fescue

Frederksen's fescue, fétuque de frederiksen

Habit Plants densely cespitose, without rhizomes. Plants densely cespitose, without rhizomes.
Culms

25-85 (100) cm, usually smooth, glabrous, occasionally scabrous below the inflorescences.

(5)10-35 (45) cm, pubescent near the inflorescence.

Sheaths

closed for less than 1/2 their length, smooth or scabrous, rarely pilose, persistent;

collars glabrous;

ligules 0.2-0.6 mm;

blades (0.3)0.5-0.9(1.5) mm in diameter, conduplicate, abaxial surfaces smooth or scabrous, adaxial surfaces scabrous or pubescent, rarely pilose, often glaucous or bluish, veins (3)5(7), ribs (1)3-5, well defined;

abaxial sclerenchyma in 5-7 wide, irregular strands;

adaxial sclerenchyma absent.

closed for about 1/2 their length, glabrous or puberulent, persistent;

collars glabrous;

ligules 0.2-0.5 mm;

blades 0.5-0.8 mm in diameter, conduplicate, abaxial surfaces glabrous, smooth or scabrous, adaxial surfaces scabrous or hirsute, veins (3)5-7, ribs 3-5, 1 distinct and 2-4 indistinct;

abaxial sclerenchyma in 3-7 broad, sometimes confluent strands, covering 1/2 or more of the surface.

Inflorescences

(5)7-15(20) cm, loosely contracted or open, with 1-2 branches per node;

branches usually somewhat spreading at maturity, sometimes erect, rarely reflexed, lower branches with 2+ spikelets.

(1.5)2-10 cm, contracted, with 1(2) branches per node;

branches erect, stiff, lower branches with 2+ spikelets.

Spikelets

(5.8) 7.5-13.5(19) mm, with (2)4-7(9) florets.

pseudoviviparous, varying in length with the stage of vegetative proliferation, the glumes and often 1 or 2 adjacent florets more or less normally developed or only slightly elongated, the distal florets replaced by leafy bracts.

Glumes

exceeded by the upper florets, ovate-lanceolate to lanceolate, mostly smooth, sometimes scabrous distally;

lower glumes 2.4-5(6) mm;

upper glumes 3-6(8) mm;

lemmas 5-8.5(10) mm, scabrous at the apices, awns (1.5)3-6(7) mm, usually more than 1/2 as long as the lemma bodies;

paleas shorter than to about as long as the lemmas, intercostal region scabrous or puberulent distally;

anthers 2.4-4.5 mm;

ovary apices glabrous.

ovate-lanceolate, densely puberulent to pubescent throughout;

lower glumes 2-4.5 mm;

upper glumes (2.7)3.8-5.2 mm;

normal lemmas 3.5-5 mm, densely hairy to pubescent, sometimes awned, awns to 0.2 mm;

vegetative bracts unawned, leaflike, sometimes with ligules;

paleas usually reduced or absent, well-formed paleas about as long as the lemmas;

anthers usually poorly developed and the pollen sterile, well-formed anthers to about 2.5 mm;

ovary apices glabrous.

2n

= 28.

= 28.

Festuca idahoensis

Festuca frederikseniae

Distribution
from FNA
AZ; CA; CO; ID; MT; NM; NV; OR; SD; UT; WA; WY; AB; BC; SK
[WildflowerSearch map]
[BONAP county map]
[BONAP county map]
Discussion

Festuca idahoensis grows in grasslands, open forests, and sagebrush meadow communities, mostly east of the Cascade Mountains, from southern British Columbia eastward to southwestern Saskatchewan and southward to central California and New Mexico. It extends up to 3000 m in the southern part of its range. It is often a dominant plant, and provides good forage. The young foliage is particularly palatable.

Festuca idahoensis differs from F. arizonica (see previous), with which it is sometimes confused, in its less prominently ribbed blades and glabrous ovary apices. It has frequently been included in F. ovina (p. 422).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Festuca frederikseniae grows on cliffs, rocky or sandy barrens, and alpine regions in southern Quebec (Mingan and Anticosti islands), Newfoundland, southern Labrador, and southern Greenland. It differs from F. vivipara (L.) Sm. of northern Europe and Asia in having densely pubescent spikelet bracts and fascicles, and an interrupted rather than continuous band of blade sclerenchyma. Frederiksen (1981) reported that F. vivipara occurs in southeastern Greenland, overlapping the range of F. frederikseniae and extending as far north as the southerly occurrences of F. viviparoidea subsp. viviparoidea; her paper should be consulted when trying to distinguish the complex pseudoviviparous fescues of Greenland.

In Iceland and southern Greenland, putative hybrids between Festuca frederikseniae or F. vivipara and F. rubra (p. 412) have been reported, and named F. villosa-vivipara (Rosenv.) E.B. Alexeev. These plants are highly variable but, unlike F. frederikseniae, produce extravaginal shoots, have closed sheaths, and have blades about 1 mm wide, with 7-9 small strands of abaxial sclerenchyma. Such hybrids can be expected within the range of F. frederikseniae in North America.

Festuca frederikseniae has frequently been included in F. ovina (p. 422).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 24, p. 438. FNA vol. 24, p. 436.
Parent taxa Poaceae > subfam. Pooideae > tribe Poeae > Festuca > subg. Festuca > sect. Festuca Poaceae > subfam. Pooideae > tribe Poeae > Festuca > subg. Festuca > sect. Festuca
Sibling taxa
F. altaica, F. amethystina, F. arizonica, F. auriculata, F. baffinensis, F. brachyphylla, F. brevissima, F. californica, F. calligera, F. campestris, F. dasyclada, F. earlei, F. edlundiae, F. elmeri, F. filiformis, F. frederikseniae, F. glauca, F. groenlandica, F. hallii, F. heterophylla, F. hyperborea, F. lenensis, F. ligulata, F. minutiflora, F. occidentalis, F. ovina, F. paradoxa, F. prolifera, F. pseudovivipara, F. roemeri, F. rubra, F. saximontana, F. sororia, F. subulata, F. subuliflora, F. subverticillata, F. thurberi, F. trachyphylla, F. valesiaca, F. versuta, F. viridula, F. viviparoidea, F. washingtonica
F. altaica, F. amethystina, F. arizonica, F. auriculata, F. baffinensis, F. brachyphylla, F. brevissima, F. californica, F. calligera, F. campestris, F. dasyclada, F. earlei, F. edlundiae, F. elmeri, F. filiformis, F. glauca, F. groenlandica, F. hallii, F. heterophylla, F. hyperborea, F. idahoensis, F. lenensis, F. ligulata, F. minutiflora, F. occidentalis, F. ovina, F. paradoxa, F. prolifera, F. pseudovivipara, F. roemeri, F. rubra, F. saximontana, F. sororia, F. subulata, F. subuliflora, F. subverticillata, F. thurberi, F. trachyphylla, F. valesiaca, F. versuta, F. viridula, F. viviparoidea, F. washingtonica
Synonyms F. idahoensis var. oregona F. vivipara subsp. hirsuta
Name authority Elmer E.B. Alexeev
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