This section is from the book "Wayside And Woodland Blossoms", by Edward Step. Also available from Amazon: Wayside And Woodland Blossoms: A Guide To British Wild-Flowers.
First and foremost in any list of British trees should come the Oak, in utter disregard of all botanical classification, for not only was our supremacy of the sea and our existence as a nation gained by aid of our oaken walls, but a grand old Oak is finely typical of British solidity, strength and endurance. Fifteen years may be regarded as the average age at which the oak first produces its fruit, the acorn, and it continues to ripen its annual crop for centuries. Dryden has certainly not exaggerated in his lines that tell how "The monarch oak, the patriarch of trees, Shoots rising up, and spreads by slow degrees ; Three centuries he grows, and three he stays, Supreme in state, and in three more decays."
According to the records and traditions relating to many hollow ruins of enormous girth still living at their circumference though long since dead at heart, Dryden's nine-century tree is only middle-aged. Well-nigh every district in this country, not too high above sea-level, can show its monster Oak; but it is where the soil is close and heavy that it is seen at its best. There is no doubt about the Oak being a true native. Some of our Oak-forests are older than history: such was the forest of the Weald - Anderides-leag - in which the aboriginal Britons so long withstood the attempts of Romans and English to conquer them, and which at a much later date supplied alike much iron from its quarries and the oak charcoal wherewith to smelt it; and of which to-day the pedestrian-tourist from London to the South Coast will cross many considerable fragments. How widely it was grown is evident from the vast number of place-names of which it forms part, such as Okham, Ockshott, Ockley, Acton, Acworth, Acrington, Okehampton, Oxted, etc.
Our British Oak is Quercus robur, of which there are several varieties to which some authorities give specific rank, but their characters are too inconstant to be so regarded-However, as they are frequently called by their distinctive names, it were well to mention them and their chief differences.
White Oak (Q. robur, var. pedunculata) has the leaves slightly stalked or stalk-less, and the acorns with long, slender stalks.
Red Oak (Q. robur, var. scssiliflora) has the leaves borne on long yellow stalks, and the acorns supported on very short stalks, or quite stalkless (sessile).
Durmast (Q. robur, var. intermedia), with acorns and leaves on short stalks, and the underside of the leaves downy. Spiders are said to object to the wood of this tree, and will not spin their webs where it has been used for building purposes.
The flowers of the Oak are of two distinct sexes. Those bearing stamens are grouped on a long, slender and pendulous catkin; each consisting of a four- to seven-lobed calyx, within which are ten stamens. The females are solitary and erect, consisting of a cupule, within which is a three- to eight-lobed calyx, a three-celled ovary with three styles. The cupule becomes the familiar "cup" of the acorn, which again is the enlarged ovary, two cells of which have aborted. Flowers April and May.
Quercus robur, var. pedunculata. - Cupuliferae. The Oak forms the world of a great number of insects, many of which are either parasites (gall-flies which produce Oak-apples, bullet-galls, spangles, and other forms of gall) or their lodgers. Several fungi, too, specially select old Oaks upon which to live freely. Chief among these is the remarkable Beef-steak fungus (Fistulina hepatica), of which in October a hundred-weight might be quickly gathered in an oakwood.