According to Koch,[1] this is a good species, growing as a shrub on the southeastern slope of the Caucasus, and having a very short stem from which spring many upright branches. Koch, however, did not find it in flower or fruit; and as no plane has been observed growing wild in the Caucasus, it is probable that what he saw were stunted trees of ordinary Pl. orientalis, occurring as escapes from cultivation.
At Grayswood, Haslemere, there are two plants, 4 feet high, with a fastigiate habit, which Mr. Chambers raised eight years ago, from seed sent from Kashmir.
4. Var. digitata, Jankó, in Engler, Bot. Jahrb. xi. 412 (1890).
- Platanus digitata, Gordon, Garden, 1872, p. 572.
This is a form of var. typica, in which the leaves are smaller than usual, with wider and deeper sinuses, the lobes extending three-fourths the depth of the blade and having large triangular toothed lobules.
Gordon supposed this form to be a native of the Caucasus, and says that it was introduced by Messrs. Loddiges in 1842. He describes the fruiting heads as only half the size of those of the type; but in the number and structure of the component achenes there is no difference.
5. Var. acerifolia, Aiton, Hort. Kew, iii. 304 (1799).
- Platanus acerifolia, Willdenow, Sp. Pl. iv. 474 (1805). London Plane. Maple-leaved Plane.
A tree, with a tall upright stem, giving off shorter branches than the typical form. Leaves (Plate 204, Fig. 1) large, at least 8 inches wide by 7 inches long, with five short, broad, triangular lobes, separated by wide rounded or acute shallow sinuses, which only extend one-third the length of the blade; base truncate or widely cordate, the lamina often descending on the midrib a short distance below the insertion of the two main lateral nerves. Fruiting heads very variable in size and in number on the peduncle, often badly developed in English trees; achenes similar in structure to those of the typical form, and never resembling those of P. occidentalis.
Several forms of the London plane have been distinguished:—
Var. pyramidalis. Pyramidal in habit.
Var. kelseyana. Leaves variegated with yellow.
Var. Suttneri. Leaves creamy-white, more or less splashed or streaked with green, often very large, as much as 12 inches wide by 10 inches long. This is identical with var. argenteo-variegata, which was exhibited at the Royal Horticultural Society in July 1897, by Messrs. Russell of Richmond. It is one of the handsomest of variegated trees, the variegation usually lasting the whole season.[2]
A form with large leaves has been sent out under the misleading name of var. californica.
Though var. acerifolia exhibits a wide range of variation in the cutting of the leaf, it always shows very distinct lobes, and cannot be confused with P. occidentalis, in which the lobes are indistinctly marked.
