½ inch in length. Above these on the stem follow the true leaves, the first and second orbicular in outline; the third and fourth showing lobes; all have long slender petioles. The first year's growth terminates in a bud just above the insertion of the fourth leaf. The primary root gives off a good many lateral fibres, which are delicate and brittle. Seedlings which germinated at Colesborne early in June were 3-4½ inches high in August, with roots of about the same length or slightly shorter. According to Elwes there was no marked tendency to form a tap-root in any of the specimens which he examined.
Varieties
Several forms are in cultivation, which differ from the wild tree in habit, in form and colour of the leaves, and in colour of the flowers.
1. Var. pyramidalis, Lavallée.—Tree with erect branches, forming a narrow pyramid, like the fastigiate oak.
2. Var. integrifolia, Kirch.—Leaves rounded at the base and without lobes. In this form, the shape of the leaves of seedling trees is preserved.
3. Var. obtusiloba, Pursh.—Leaves with only one rounded lobe on each side of the base.
4. Var. heterophylla.—Foliage variable; some leaves being entire, others with lobes, which are acute or obtuse.
5. Var. crispa.—Leaves with undulate margins.
6. Var. variegata.[1]—Forms, with variegated leaves, of which several sub-varieties have received names, as argenteo-variegata, aureo-variegata, medio-picta. That known as aureo-marginata[2] in which the edges of the leaves are yellow is the best.
7. Var. aurea.—Flowers yellow.
Identification
In summer, the shape of the leaves is unmistakable, resembling those of no other hardy tree: the variety integrifolia, though without lobes, preserves the truncate, slightly emarginate apex, in the centre of which may be seen the midrib prolonged as a short bristle.
In winter, the twigs and buds are very characteristic. Buds: terminal, larger than the lateral, which are alternate on the twigs, and arise from them at an angle of 45°. They are stalked, glaucous, glabrous, composed of 2 stipules joined together by their edges, forming a closed sac, in which is contained the young shoot;[3] and on opening it a leaf will be seen embracing an interior bud. It is folded on its mid-rib with the stalk bent like a hook, bringing the apex of the leaf to the base of the bud. The twigs are glabrous, shining brown or slightly hoary, and marked by stipular rings just above the leaf-scars, which are circular, placed obliquely on prominent cushions, and dotted like a sieve with cicatrices of the fibrous bundles. The lenticels are few
- ↑ The variegated form in which the yellow marking occurs as irregular blotches in the central part of the leaves is well depicted in Lemaire, Illust. Horticole, xv. t. 571 (1868).
- ↑ A good figure of the variety is given in Flore des Serres, xix. 2025 (1873).
- ↑ Within the outer bud or sac are contained several younger buds, one within the other, each with a folded leaf.
