A tree at present about 70 ft high at Kew; young shoots with a close covering of very short erect hairs (velutinous). Leaves with mostly eleven leaflets, but here and there with five to nine or thirteen leaflets; petiole and rachis spreading pubescent; leaflets elliptic or oblong-elliptic to lanceolate or sometimes broad elliptic, acuminate at the apex and long cuneate at the base, mostly distinctly stalked (petiolulate), with the stalks up to 1⁄3 in. long, but sometimes almost sessile; the leaflets are mostly 13⁄8 to 23⁄4 in. long and 1⁄2 to 3⁄4 in. wide and widely serrulate to serrate, but sometimes up to 3 by 11⁄4 in. and coarsely serrate, sparsely pubescent above, more closely so on the lower surface, mostly on the veins and markedly so on the midrib, which is more or less densely spreading pubescent. According to Koehne the flowers have hairy ovaries, a most unusual feature among the ashes. Fruits not seen.
F. holotricha was described in 1906 from a plant first noticed in Späth’s. arboretum though others were afterwards found in the Berlin and Dresden Botanic Gardens, all under the name F. potamophila (a synonym of F. sogdiana, q.v.). The above description was made from a tree at Kew which was received from Späth in April 1909 and now measures 72 × 41⁄2 ft (1969). The native home of this species was not well known when Koehne described it, but specimens in the Kew Herbarium from Ilfov, Rumania, agree with it.
F. pallisiae Wilmott F. holotricha sensu Borza, not Koehne – This species, much resembles F. holotricha in the hairiness of all its parts, including the ovary. It differs in being even more hairy and in the leaflets being sessile or almost so. The stems are notably spreading pubescent in addition to having a covering of fine short hairs; the leaves have usually nine to thirteen leaflets, sometimes five to seven, the petiole and rachis are densely spreading-pubescent; leaflets rounded or obtuse to wide cuneate at the base and sessile or almost so, though the cuneate base may sometimes be extended into a short petiolule, upper and lower surfaces, hairy as in F. holotricha but more densely so with rather longer hairs, so that the lower surface especially can be described as pubescent-villous.
F. pallisiae was described in 1916 from material collected in the Danube Delta by Marietta Pallis, and is found in Great Thrace, Rumania, Bulgaria, and parts of eastern Yugoslavia. It is frequently associated in the wild with F. oxycarpa. In the Botanical Magazine, n.s., in the article accompanying t. 370, the late Dr Turrill suggested that the variability of F. pallisiae was due to the introgression of genes from F. oxycarpa. For a further discussion see Kew Bulletin (1935), pp. 132-141 and New Phytologist, Vol. 37 (1938), pp. 160-172.
F. pallisiae is represented in the Ash collection at Kew by several trees raised from seeds collected by B. Stefanoff in the Strandja Planina region of E. Bulgaria in 1932. The most notable of these is No. 364 near the end of the Lake, which now measures 42 × 31⁄4 ft (1969). The material for the figure in the Botanical Magazine was, however, taken from a tree in the Experimental Ground at Kew, raised from seeds collected in western Thrace, in 1935.