Tree Species Families
BROADLEAF TREES are classed as Angiosperms. Angio comes from the Greek for “vessel”. So an Angiosperm has its seeds in a vessel, in this case an ovary. Broadleaf trees generally have wide leaves with veins. Broadleaf trees bear flowers and fruits, not cones. Wood from Broadleaf trees is called Hardwood. Oak, Beech, Walnut, Lime, Poplar, Sycamore and Ash are all European hardwoods used in furniture manufacture. To learn more about Broadleaf Tree families click HERE.
CONIFERS are classed as Gymnosperms because they have “naked seeds” which are not surrounded by an ovary. Gymno comes from the Greek for “naked”. Conifers have leaves that are needle-like or scale-like. They bear pollen and seed cones, not flowers and fruit. The word “Conifer” means cone-bearing. Wood from Conifers is called Softwood. Pine, Spruce, Cedar and Cypress are softwoods used in furniture manufacture. Only three conifers grow naturally in Britain – Scots Pine, Common Juniper and Yew. All the others have been introduced. To learn more about conifer families click HERE.
The GINKGO, also known as the Maidenhair Tree, is a Gymnosperm but is strictly not a Conifer. It has catkin-like pollen cones like a Conifer but does not produce seed cones. Its seeds develop into round green fruits on the end of stalks. The fertilisation process involves motile sperm, a feature of Mosses, Liverworts and Ferns. Hence it is in a botanical class of its own and is often referred to as a “living fossil”. To learn more about the Ginkgo family click HERE
In the Field Guide to Trees of Britain and Europe the families and genera are arranged according to the linear sequences published by Christenhusz et al. (2011) for Gymnosperms and by Haston et al. (2009) for Angiosperms. Botanical institutions organize their collections in linear sequences that reflect evolutionary relationships, rather than arranging them alphabetically. Various linear sequences have been proposed over the years but these sequences, based increasingly on DNA analysis, are now considered to be the most reliable. Note that since the sequence is generated from an evolutionary tree, the closer in the sequence the families are, the more they should have similarities.
Some families include a number of common trees. These families are shown below in their correct linear sequence. Note that in the latest publications, Maples and Horse Chestnuts are now part of an expanded Soapberry family (Sapindaceae). In the conifer table the term Cypress includes the genera Cupressus and ChamaecyparIs and Sequoia includes the Coast Redwood, Dawn Redwood and Giant Sequoia.
In this table the Rose family includes the genera Sorbus and Prunus. The Sorbus genus includes the Common and Swedish Whitebeam, the Rowan and the Service Tree. The Prunus genus includes the Wild Cherry (and all its Flowering Cherries), the Plum Cherry, the two Laurels (Cherry and Portugal), and the Bird Cherry,