As we have seen, conifers are Gymnosperms and bear naked seeds. All those I llustrated on the following pages are included in the order Coniferales with the exception of Taxus (Taxales} and the unique Ginkgo (Ginkgoales). The order Coniferales is usually divided into six or seven "families, but the allocation of genera to these is rather a matter of opinion. This need not concern us here except to note that the largest family. Pmaceae, includes the important genera Pinus, Picea, Abies, Cedrus, Larix, Tsuga and Pseudotsuga.

Conifers are generally sombre evergreen trees of pyramidal habit but a few, e.g. Larix and Taxodium, are deciduous. They range in height from small bushes (Juniperus) to the tallest known trees (Sequoia). Tbere are only three native Gymnosperms in Britain, the Scots Pine, Common Juniper and Yew, and these are easily recognized. The conifers are predominantly temperate plants and many introduced species grow well in this country and are often planted for both forestry and ornament. Cones are useful aids to identification but are not always produced readily in Britain or, if they are, may be borne so high that they are difficult to reach. However, the characters of the foliage are also important and the simple key on the next two pages plus the illustrations and descriptions following should enable the reader to identify our commoner coniferous trees. Important features to look for are the form of the leaf, whether scale-like, needle-like or linear, and its mode of attachment to the stem. The Pines can be recognized by their two to five needle leaves borne on dwarf shoots. The needle leaves of both Firs and Spruces are inserted singly on the stem but their leaf scars differ.

Was this article helpful?

0 0

Post a comment