Today I went out on my lunch break to an excellent grassy scrubby bank next to the railway near my office, looking for two more leaf characteristics, pinnate and pinnatifid. They make a similar pair as yesterday's palmate and palmately lobed leaves did. Pinnate means a compound leaf that is subdivided into leaflets, as a palmate leaf is, but instead of the leaves all spreading out from one point at the top of the stalk, they are arranged along the stalk on either side of it. A pinnatifid leaf has its veins arranged in the same way, spreading out from a central line instead of a central point as in a palmately lobed leaf, but instead of being subdivided into leaflets it is only deeply cut into pinnately-arranged lobes.
|Pinnate leaves on Common Vetch (Vicia sativa).|
|Pinnatifid leaves on Pedunculate Oak (Quercus robur).|
|Comparing pinnate and pinnatifid leaves (the vetch is face-down as it wouldn't stay flat the right way up!).|