Graminae

Synonyms

Avena elatior L.

There are two subspecies. The subsp. bulbosum (Willd.) Schubler et Martens (Syn.: var. bulbosum (Willd.) Spenner) is rare in grassland, it is a weed in arable land. It has a more southern and western distribution than the subsp. elatius.

Common names

Tall oatgrass (English), Fromental (French), Glatthafer (German).

Description

Perennial plant, robust, hairless to more or less hairy, cespitous. Stems erect, 60 - 150 (- 180) cm high. Blade rolled when young, large, often slightly narrowed on the upper third, hairless or hairy. Ligule average, almost 1.5 mm long, truncated. No auricles. Panicle like inflorescence, 10 - 30 cm long, more or less spreading. Spikelets (2 -) 3 - flowered. The lower flower usually male with a long bent awn on the lemma, the second hermaphrodit with usually a shorter awn on the lemma, the upper sterile. The weight of 1000 seeds is 2.50 to 3.53 g (big seeds). Chromosome number: 2n = 28.

Temperature

Although well adapted to continental climates, dislikes late frosts. Does not tolerate shade. In oceanic climate, likes particularly south facing slopes where the microclimate is warmer.

Water

Very resistant to summer drought.

Soil

Optimum on well drained and dry soils.Very sensitive to soil humidity; it vanishes with winter floodings. Never on peat soils. Likes average to nutrient rich soils. Does not tolerate acidity, widespread on neutral to alcaline soils. Not very demanding for soil texture but optimum on mid-heavy (loam, sandy-clay) and light (sandy-loam, sand) soils.

Distribution

Native to Europe, West Asia and North Africa. Has become subcosmopolitan, in temperate regions. Disappears in altitude where it is taken over as dominant grass in hay meadows by Trisetum flavescens.

References