Monday, 16 May 2011

Pre-nuptial botany

Don’t get too excited folks, I just mean before the flowers come out! Incidentally, the word gamete (sex-cell) actually comes from the Ancient Greek for husband and wife.

Identifying plants without flowers is known as vegetative identification and is extremely useful if you want to identify all the plants (above-ground!) at a site in one visit. The wonderful thing about learning vegetative identification is that it makes one look very closely at a plant. One may start botany by identifying the showier herbs and most obvious trees, but, for an intimate knowledge of plants and how to identify them using keys, training your hand-lens on cilia or hydathodes is where it’s at. Luckily a Vegetative Key to the British Flora  (J. Poland & E. Clement; known as ’Poland’) has recently been published, and is available on Amazon.

As an example of the benefits of such knowledge, a recent walk in the Rivelin Valley (Sheffield) to see that “loveliest of trees”, the cherry, yielded the flouncy white flowering spikes of the Bird Cherry (Prunus padus). Even without flowers this can be quickly separated from almost every other Prunus except Rum Cherry (Prunus serotina) by the strongly smelling pith of the twigs (a useful winter ID trick). The heart-shaped (cordate) leaf bases allow us to decide between these two on Bird Cherry: few other books besides the Vegetative Key give you this information. 

However, vegetative characters may not solve all of our problems, elsewhere in the valley I encountered a sapling of a Whitebeam (Sorbus spp.) and a large Cotoneaster shrub. Whitebeams and Cotoneasters are both members of that prudish coterie of plants that often go without sex; one of the upshots of this is that clonal reproduction may result in numerous ‘micro’-species with few obvious differences to help the field botanist. This is where we will want to confirm our identifications by taking so-called ‘voucher’ specimens. Understandably, an identification in a database of a difficult plant species that is not backed up by a voucher will likely be discarded by future botanists as unreliable. 

The Botanical Society of the British Isles ( is there to help botanists in this respect: their network of referees (including a ‘Beginner’s referee’) will check member’s specimens, confirming or questioning their identity. The wonderful thing about botany today is the amount of excellent material and support that is available to the enthusiastic. So, to paraphrase (or butcher!) Housman: since fifty springs are little room, to learn about the things in bloom, I’ll go with Poland and a press, so next year I won’t have to guess.