Not to be semantically confused with :
Bird's-foot Clover (aka
Fenugreek) (Trifolium ornithopodioids) [a Clover belonging to the same Pea Family] nor to Bird's-Foot (Ornithopus perpusillus) nor
Orange Bird's-foot (Ornithopus pinnatus) [Bird's-foot's belonging to the same Pea Family]. Nor to Hare's-Foot Clover (aka
'Hare's-foot Trefoil')(Trifolium arvense) nor with the true Trefoils (Trifoilium such as Hop Trefoil (Trifolium campestre), Lesser Trefoil (Trifolium dubium) or
Slender Trefoil (Trifolium micranthum) - [all plants with similar names and belonging to the same Pea Family (Fabaceae) but in differing genera]
Easily mistaken for other Bird's-foot-Trefoils such as :
- Common Bird's-foot-Trefoil (Lotus corniculatus) but that has slightly shorter pods 15-30mm (rather than up to 35mm of Greater B-f-T), has fewer flowers (1-2 to 7 (rather than 5-7 of Greater B-f-T) and is also ubiquitous.
Narrow-leaved Bird's-foot-Trefoil (Lotus tenuis) usually only 2-4 flowers (but can have 1 to 6) with linear to linear-lanceolate leaves (rather than ovate to obovate of Greater B-f-T) and found mainly in the SW of England.
Hairy Bird's-foot-Trefoil (Lotus subbiflorus) is always hairy, is an annual (rather than perennial) and is quite rare (RR).
Slender Bird's-foot-Trefoil (Lotus angustissimus) is always hairy, is an annual, but is very rare (RRR) found only in the far South of England.
Distinctive features of Greater Bird's-foot-Trefoil over all others is that: It has hollow stems (only rarely hollow in Common B-f-T and Narrow-leaved B-f-T), it has 5-12 flowers (all others less than 7), it has three sepal teeth that are re-curved in bud, the other two with an acute-angled notch between them, fruit pods 15-35mm long (a max of 30mm in all others).
No relation to :
Bird's-foot Sedge (Carex ornithopoda) [a sedge with similar name].
Slightly larger than the next largest, being Common Bird's-foot-Trefoil
Greater Bird's-foot-Trefoil is an erect native perennial growing to 1m in damp places such as marshes, side of ponds, and damp grassland and woodland rides. It is ubiquitous found almost throughout the British Isles except the highest ground in Scotland.
The 'trefoil' part of the name derives from the terminal triplet of leaves. The 'bird's-foot' from the shape and form of the seed-pods (although your Author wonders about those birds with up to 12 toes [aka pods]).
Bird's-foot Trefoils, like many other plants belonging to the Pea Family, contain poisonous Cyanogenic Glycosides.