tomentose

Before undertaking to pursue the subject further, it should be understood words do not always express an exact meaning. For example, “Pubescent” is described as, “covered with hairs, particularly if short and soft.” “Tomentose” means, “with dense wooly pubesence.” Now, this is all very well, but the exact difference is not clear, and what one man may believe is pubescent, another may call tomentose. And here’s the rub: a key based on the assumption that words alone can express an exact meaning, and therefore can be interpreted precisely as intended, may be misleading, unless the reader knows enough of the author’s work to be able to decide how a particular word should be interpreted. This may seem farfetched, but is probably the main stumbling block in following a botanical key. Therefore take heed of this, and much disappointment will be avoided.
George W.D. Symonds