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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![Ill] BUD-SCALES We have seen that the bud-coverings are essentially leaf-structures. Sometimes these bud-coverings are merely unaltered leaves, just like any other leaves of the plant, and this is probably always the case wheu the bud is merely the end of the still growing shoot, as in most herbaceous plants; but even in buds which are adapted for resting through the winter this is sometimes so. Such naked buds occur in Viburnum nudum, V. Lantana, Rhamnus Frangula, Juniper, and many herbs. As a l'ule, however, the winter buds of our colder climates are covered with bud-scales of quite different texture from the foliage leaves : these scales are thrown off in the spring when the buds expand. The bud-scales may be simply dry, papery or leathery in texture, and brown (Beech, Prunus Avium), or greenish (Lilac, Acer pseudoplatanus); or more or less hairy (Juglans, Betula pubescens, Carpinus, Ulmus, &c.), velvety (Ash), glandular (Hippophae, Elceagnus, Betula verrucosa), or viscid, owing to resinous or gummy excretions (Alnus glutinosa, Popidus canadensis and P. nigra, and Horse-chestnut). In all these cases the texture, hairy covering, and resinous or balsamic excretions are protective, in that they prevent rapid changes of temperature and especially loss of moisture, and this protection is sometimes supplemented by cottony hairs covering the young organs inside the scaly covering, e.g. the Horse-chestnut. The bud-scales (apart from those cases where they are obviously ordinary leaves) may be seen to be more or less modified leaves by tracing them from without inwards as the bud opens in spring. In the Lilac, Lonicera and Daphne the scales pass gradually into ordinary leaves and are modified forms of their blades: in Magnolia, Liriodendron, Alder, Beech, Oak, Ficus elastica and many others the bud-scales are stipules, the leaves to which](https://iiif.wellcomecollection.org/image/b2805717x_0001_0047.jp2/full/800%2C/0/default.jpg)
