Volume 1
Trees : a handbook of forest-botany for the woodlands and the laboratory / by H. Marshall Ward.
- Wellcome Trust
- Date:
- 1904-09
Licence: In copyright
Credit: Trees : a handbook of forest-botany for the woodlands and the laboratory / by H. Marshall Ward. Source: Wellcome Collection.
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![CH. IV] OPPOSITE AND ALTERNATE BUDS It is the rule where buds, leaves, &c., are opposite, that each alternate pair is directed at right angles to the pairs immediately above and below on the twig, and this decussate arrangement, as it is termed, prevails in all the genera in the above list. Cases occur, however, where buds which are not truly opposite, or not consist- ently so, but so nearly so as to be termed sub-opposite, are not always at the same time decussate. Examples are afforded by Picea excelsa Rliamnus catharticus Abies pectinata Salix purpurea. In some of these cases, indeed, the buds, though strictly speaking not inserted at the same level, appear to be so arranged in whorls, or groups clustered round the stems in a radiating manner, that the shoots to which they give rise present the appearance of being in verticels, or regular tiers, at definite intervals. It is to this that the pseudo-whorls or false verticels of the following ai’e due:— Pines Spruces Silver Firs, and, in a less pronounced degree, a similar arrangement occurs in Larch Ash Oak Cherry Bird Cherry Holly. In the following, the buds are alternate, that is to say each bud stands isolated at its own node, the insertions being either alternately right and left of the twig bear- ing them, so that they are two-ranked (distichous) if regarded as to the vertical series formed by joining all the buds up the twig standing one over the other; or there are three or five such vertical series or ranks. In this latter case, a line joining each and every bud-inser- tion in succession would pass more or less spirally round](https://iiif.wellcomecollection.org/image/b2805717x_0001_0051.jp2/full/800%2C/0/default.jpg)
