• GENERAL BOTANICAL CHARACTERISTICS
• RAUNKIAER LIFE FORM
• REGENERATION PROCESSES
• SITE CHARACTERISTICS
• SUCCESSIONAL STATUS
• SEASONAL DEVELOPMENT

GENERAL BOTANICAL CHARACTERISTICS:

Individual rough fescue plants often form large-diameter bunches. Moss and Campbell [85] reported crown diameters of 10 to 20 inches (25-50 cm) on undisturbed sites in Alberta. In quaking aspen parklands of Saskatchewan, plant diameters rarely exceed 5 to 6 inches (13-15 cm). Plants have an extensive fibrous root system that can reach more than 4 feet (120 cm) in depth on sites in the black soil zone in Saskatchewan. Approximately 73% of the root system is concentrated in the top 6 inches (15 cm) of soil. On these sites, average yield of underground fescue parts to a depth of 4 feet (1.2 m) is estimated at approximately 11.11 tons/acre [24].

Culm height, color, and other characteristics differ by subspecies [87]. Subspecies of rough fescue are distinguished primarily by growth habit and other morphological characteristics, and there is overlap among the subspecies. Botanical characteristics of the subspecies follow.

Northern rough fescue tends to have yellowish- to dark-green foliage. Plants are densely caespitose with short, inconspicuous to infrequently present rhizomes [1,87]. Plants produce 5 to 10 culms that are 16 to 24 inches (40-60 cm) in height, and have 3 to 5 florets per spikelet [48,87]. 

Mountain rough fescue is bluish gray-green, densely caespitose, and rarely has rhizomes [48,87]. It is relatively tall and forms large clumps consisting of up to 25 culms [87]. Culms generally range from 16 to 36 inches (40-90 cm) in height, with 4 to 6 florets per spikelet [1]. Mountain rough fescue has double the chromosome number of the other 2 subspecies [87].

Plains rough fescue is somewhat rhizomatous and mat forming in habit. Plants are bluish or gray-green bunchgrasses with short rhizomes. Plants produce 3 to 5 culms that range from 8 to 26 inches (20-65 cm) in height. There are 2 to 3 florets per spikelet. Plants are relatively short, less strongly tufted than the other subspecies and produce short, creeping rhizomes [1,67]. Dead sheaths persist at the base of plants [1].

RAUNKIAER [91] LIFE FORM:

REGENERATION PROCESSES:

As is the case with the majority of cool season grasses, the seed crop of any year is initiated and partially develops during the fall. Final seedhead maturation occurs the next summer. Vegetative buds are maintained throughout the year at approximately 0.09 inch (2.3 mm) above the root-stem transition. Floral initiation occurs primarily during late August and early September. Reproductive apices are gradually elevated to 0.6 inch (15.2 mm) during the winter months. Rapid culm elongation occurs during May and early June [104].

Variation in year-to-year germination and seed production has been reported. Seed production is not related to basal area or the number of tillers per plant. Although factors responsible for erratic seed production in rough fescue are unknown, Stout and others [104] suggest that environmental factors can have a significant impact when seed development occurs over a prolonged period. Their studies indicate that low temperatures enhance seed development.

Griltz and others [46] report that "persistence of viable rough fescue seed in the soil is low." In Alberta, the number of viable seed per m² of rough fescue decreased with grazing [61]. According to Griltz and others [46] germination in rough fescue is primarily controlled by water stress and not temperature. For example, plains rough fescue is known to germinate over a wide range of temperature. Germination was found to be highest at constant temperatures of 59 and 68 ^oF (15 and 20 ^oC) [94]. Germination of rough fescue is reduced by exposure to moist conditions at low temperatures [46]. Johnston and MacDonald [60] reported germination rates of 86 to 96.5% during field trials in southern Alberta. Details on germination characteristics of rough fescue by temperature, light, and osmotic potential are available [46,94,99,100].

Stands typically take from 3 to 4 years to fully develop. Initial establishment is enhanced on sites that receive protection from grazing. The establishment of plains rough fescue is likely to be highest where plants have died or where competition is reduced at some distance from established plants [46].

Plains rough fescue, which grows along the foothills and in mountain grasslands of the Rocky Mountains, is rhizomatous. In Alberta, bunches are connected by short rhizomes to form a large, loosely consolidated crown. Rhizomes emerge either laterally or from underneath the crown and radiate in all directions. Sprouts are then produced within approximately 0.8 inch (2 cm) of the parent plant. Maximum root depth is 6 inches (15 cm). Maximum rhizome lengths are approximately 23 inches (60 cm). Vegetative regeneration in plains rough fescue may be reduced by heavy grazing. Plains rough fescue produces seed only infrequently [94].

Northern rough fescue has short inconspicuous rhizomes [1]. 

Mountain rough fescue is a bunchgrass and rarely produces rhizomes [48,87]. Mountain rough fescue tillers appear to survive "several" years and become larger with age [40]. Most tillers are vegetative and lack culms [118]. Seed production is erratic. Several years may elapse without any appreciable seed set. Important seed years in southern Alberta were 1902, 1952, 1964, and 1966 [60].

SITE CHARACTERISTICS:

Rough fescue grows on a number of soil types including loam and silty loams [69]. In eastern North America, northern rough fescue populations are often localized. Populations are found on sand plains, serpentine barrens, limestone plains and basaltic slopes. In western North American, northern rough fescue grows in subalpine, alpine, taiga, and tundra zones in open forests, meadows, and grasslands, or in timber, rocky slopes, and plateaus [1].

Site preferences of rough fescue vary by subspecies. Mountain rough fescue is a dominant component of foothill grasslands. This subspecies occurs on more mesic and cooler sites than the other subspecies [1]. 

Topography supporting plains rough fescue ranges from level to gently rolling. Plains and mountain rough fescue are separated by elevation in southern Alberta. Plains rough fescue occupies prairie sites in central Alberta and Saskatchewan at elevations from 1,200 to 2,000 feet (366-610 m) [1].

Elevational ranges of rough fescue vary as follows [24,29,31,52,73,77,110,125]:

SUCCESSIONAL STATUS:

Northern rough fescue is common soon after fire in quaking aspen woodlands of Alaska [74]. It is also prevalent on some black spruce (Picea mariana) sites 40 to 100 years after fire in British Columbia [89]. It occurs in early stages of succession in tundra communities of the Alaska Range [113]. It is present into the early shrub stage, but does not reproduce sexually. By the late shrub stage, rough fescue is no longer present. Generalized succession in these tundra communities is as follows [113]:

Plains rough fescue is considered a climax species in grassland communities of Manitoba [6]. 

SEASONAL DEVELOPMENT:

In British Columbia, flowering typically occurs from mid-May to mid-June, with seed dispersal from mid- to late July. Maximum plant weights were not attained until late June, after culm and blade elongation had ceased [104]. Summer growth cessation is controlled primarily by available water [105]. Fall regrowth occasionally occurs in plains rough fescue in Manitoba [109]. In British Columbia, fall regrowth occurred in 2 out of 3 years in September or October. Lack of regrowth was attributed to effects of defoliation [104].

Phenological development of rough fescue over a 3-year period on 2 sites in British Columbia is presented below [104].