Salix aurita × S. repens (S. × ambigua Ehrh.), a hybrid willow
Account Summary
Native, very rare.
1946-54; MCM & D; on the shore of Lough Melvin, near Garrison.
Growth form, appearance and preferred habitats
The conspicuously ear-shaped stipules and the entire or sub-entire (ie scarcely toothed) leaf margins, the sometimes obliquely twisted leaf tip, the leaves at first coated on the upper surface with silky, white, adpressed hairs and the small size of the sprawling plant are all important recognition features. The habitat is acidic or slightly base-enriched heaths and moors, or in limestone grassland, occurring where the parent species overlap, although as with other willow hybrids, more often where one parent is more common than the other, rather than where they are equally represented (Willows and Poplars Handbook).
Fermanagh occurrence
There is only one record for this low, sprawling hybrid in our Fermanagh Flora Database made by Meikle and his co-workers on Lough Melvin near Garrison. It is undated but must fall sometime in the immediate post-war period of this group's regular summer visits. In his BSBI Willows and Poplars Handbook, Meikle (1984) regarded this hybrid as being frequent in B & I, so perhaps it is being regularly overlooked.
Irish occurrence
The FNEI 3, published eight years after the Willows and Poplars Handbook, lists ten records of this hybrid from Co Antrim (H39), all of which were made by one recorder, John Harron, during the 1970-88 period. The FNEI 3 account describes S. × ambigua as being, "frequent and widespread on the Antrim Hills". However, the Flora of Co Dublin makes no such claims regarding this subshrub, merely mentioning that a previous record (no details) was not refound on Mountpelier in District 7 of the Flora. The Irish representation of this hybrid is very poor, with just six hectads in Co Antrim (the Harron records mentioned above), and solitary hectads in four other Irish VCs, Co Kildare (H19), E Mayo (H26), Co Fermanagh (H33) and W Donegal (H35).
British occurrence
Despite Meikle's assertion that this hybrid is of frequent occurrence, the New Atlas hectad map demonstrates only a thinly scattered record of S. × ambigua exists across northern parts of B & I, with a quite marked Scottish predominance, especially on the N & W Isles. The hectad map in the Hybrid Flora of the British Isles shows a considerable increase in records right across both B & I, but the pattern of scattered sites is similar, although with more hybrid presence in the S of England. It is described by these authors as, "one of the commoner willow hybrids in northern Britain, particularly near the west coast where the parents often grow in close proximity in exposed coastal heathland and moorland" (Stace et al. 2015).
Clearly, a greater and much more focussed recording effort is required to ascertain the true extent of this hybrid, but Howitt & Howitt (1990) point out the significant and relevant fact that S. repens (Creeping Willow) flowers later than S. aurita (Eared Willow) (ie usually about the end of April), which obviously time-limits the opportunity for cross-fertilisation. The northern distribution of the records in B & I may reflect a modification of the timing of flowering of these willow species, perhaps significantly increasing the period of overlap and enabling a greater frequency of crossing.