Notes on how to distinguish frequently confused groups of “broad-leaved” woodland species. Refer to the Interactive key for more species.
In Cow Parsley, leaves are pinnately divided and in Herb Robert, leaves are palmately divided. In both species, leaflets are further divided, making it a bit difficult to notice whether the first division is pinnate or palmate. Look at the overall shape of the whole leaf – more or less triangular means Cow Parsley while rounded (or angular) means Herb Robert.
In all three species, leaves are pinnately divided with irregularly shaped leaflets. A well-developed Hogweed is easy to tell apart as its leaflets are often further divided, but a young plant might not show this. Look for the small leaflets between large leaflets in Wood Avens and Agrimony. It is better to avoid very young plants because these small leaflets might not be visible yet. Young Wood Avens might have only three leaflets, but at any stage, the terminal one is noticeably larger than the other leaflets. If the terminal leaflet is not larger than the ones below – it is likely to be Agrimony. Agrimony is not a woodland plant, but it might encroach into the woodland from a grassy ride or meadow margin.
Most people would recognise Wild Strawberry with their trifoliate leaves. Barren Strawberry has superficially similar leaves. Literature suggests that the end tooth of each leaflet is longer than its neighbours in Wild Strawberry and no longer (or shorter) in Barren Strawberry (Rose 2006, Poland & Clement 2009). I find this feature a bit confusing and rely more on hairs on the lower side – pressed to the surface in Wild Strawberry (making it silky and smooth if you stroke it) and spreading-hairy (sticking out) in Barren Strawberry. Poland & Clements (2009) mention this feature to distinguish Barren Strawberry from Garden Strawberry Fragaria x ananassa.
All these species belong to the Mint family and have square stems and leaves in pairs. In theory, White Dead-nettle and Black Horehound are plants of margins and hedges, but they do creep into the woodland along the rides. To complicate things, the leaves of Yellow Archangel vary a lot during the season – rounded early on and becoming more nettle-like later. A good feature for Yellow Archangel in winter and early spring is the trailing stem (stem lying on the ground). When plants start growing, they become upright, and the trailing stem becomes less obvious. At this stage, they can be confused with White Dead-nettle. The Latin name of Yellow Archangel Lamiastrum means “resembling Lamium”, which is the Latin name for Dead-nettle. Poland & Clement (2009) suggest that leaves are heart-shaped (cordate) in White Dead-nettle and have a straight base (truncate) in Yellow Archangel, but this is not very obvious in young Yellow Archangel. Hedge Woundwort can be easily distinguished by relatively long leaf stalks and a strong pungent smell. In the above three species, the tip of the leaf can be described as having an acute angle (less than 90 degrees). This happens because the terminal tooth is longer than wide. In Black Horehound, the end tooth is wider than long, making the leaf tip obtuse (more than 90 degrees). This seems to work in general, but do not rely on a single leaf which might not follow the pattern! All four species can be identified by smell.
A typical feature used in the keys is whether the stem is hairy all around (Wood Speedwell) or has hairs in two lines (Germander Speedwell). It is an easy feature to use when it is present. Unfortunately, Germander Speedwell might have hairs all around the stem. This is common in winter (when plants are not growing much) and in shady environments. Sometimes, the two lines can be noticed between the top 2-3 nodes on careful examination, but this is not always the case. Rose (2006) suggests that leaf stalks in Germander Speedwell are short (up to 5 mm) or none, while in Wood Speedwell they are 5-15 mm. I also use a few more subtle features, like leaves of Germander Speedwell are darker, more wrinkly and with more rounded teeth.
References
Poland J. & Clement E. J. (2009) The Vegetative Key to the British Flora: A New Approach to Naming British Vascular Plants Based on Vegetative Characters. Botanical Society of the British Isles, London, UK.
Rose F. (2006) The Wild Flower Key: How to identify wild flowers trees and shrubs in Britain and Ireland. Second Edition (Revised and expanded by C. O’Reilly). Frederick Warne.
This page is based on
Mashanova A. (2023) A few notes on identification of woodland species in the vegetative state. Transactions of the Hertfordshire Natural History Society v. 55, pp. 47-50.