Vegetative proliferation in inflorescences of red fescue (Festuca rubra s.l, Poaceae)

Abstract

A continuous range of variation in vegetative proliferation among members of the red fescue complex is documented in (ii) the number of spikelets proliferating in the inflorescence, (ii) the position where initiation of proliferation occurs, (iii) the rachilla, where abnormal elongation may result in internodes 3–10 mm long, and (iv) the position of proliferation, which may be either lateral or terminal on the rachilla. Both facultative and obligatory vegetative proliferation occur. Recorded chromosome counts of 2n = 49, 50, 63, and 70; low pollen stainability; absence of seed; and occurrence of proliferation in spikelets of known hybrids suggest that at least some specimens are the products of hybridization. In North America, the name Festuca prolifera has been applied to vegetatively proliferating specimens of F. richardsonii, F. rubra s.l,, and some specimens that may be hybrids. Although proliferating spikelets are conspicuous, they do not justify taxonomic rank.