An evergreen tree of large size, attaining in favourable places a height of 70 to 90 ft, and developing in open situations a huge head of densely leafy branches as much across, the terminal portions of the branches, usually pendulous in old trees; trunk sometimes over 20 ft in girth; young shoots clothed with a close grey felt. Leaves very variable in shape, most frequently narrowly oval or ovate-lanceolate, 11⁄2 to 3 in. long, 1⁄2 to 1 in. broad, rounded or broadly tapered at the base, pointed, sometimes entire, sometimes (especially on young trees) more or less remotely toothed. When quite young both surfaces are clothed with whitish down, which soon falls away entirely from the upper surface leaving it a dark glossy green; on the lower surface it turns grey or tawny, and persists until the fall of the leaf; stalk 1⁄8 to 5⁄8 in. long. Fruits produced one to three together on a short downy stalk, ripening the first season; acorns usually 1⁄2 to 3⁄4 in. long in this country; cups with appressed, downy scales.
Native of the Mediterranean region; cultivated in England since the 16th century. The holm oak is in many respects the finest of all evergreen trees, apart from conifers, cultivated in the British Isles. Its foliage is most abundant, and the branches form heavy dark masses on the tree. The habit of young trees is curiously diverse, some being of distinctly pendulous habit, others rigidly pyramidal. The leaves, too, vary very much in size, shape, and toothing. On strong sucker shoots I have gathered them 5 in. long and 21⁄4 in. wide, but that is very unusual. This oak likes a warm, rather light soil, and is perfectly hardy in the south and west of England, and near the coast. In very severe winters it is occasionally denuded of foliage. It thrives well near the sea, and is much planted on the sea-front of some of the southern watering-places, where it is seen as a dense, flat-headed bush, stunted, but otherwise quite healthy. It has one defect as a tree in trim gardens, due to shedding the leaves of the previous year during May and June, and making an unsightly litter day after day. One way of avoiding this nuisance is to plant the ground underneath the branches with ivy, amongst which the leaves fall and automatically disappear. Grown in wood under semi-forest conditions, the holm oak makes a tall slender trunk of rather picturesque appearance, due to the corrugation of the bark. It may also, if so desired, be clipped into rounded or pyramidal shapes and kept permanently dwarf. It should only be propagated by acorns, which it produces in quantity in dry hot seasons. The seedlings should be grown on in pots and planted out when small in spring or summer, after the first or second flush of growth is completed.
Although there are no notable specimens of Q. ilex at Kew, the species thrives well there. The plantings on either side of the Syon Vista are largely composed of this species, intermixed with forms of Q. × hispanica and Q. × turneri. The largest in the collection, by the North Gallery, measures 70 × 13 ft (1952). Other old specimens in or near London are: Chiswick House, London, 70 × 21 ft (1952); Frogmore, Berks, 55 × 191⁄4 ft (1967). Farther to the south-west the following have been recorded: Melbury, Dorset, 70 × 131⁄4 ft (1971); Knights-hayes, Devon, 82 × 203⁄4 ft at 3 ft (1959); Dartington Hall, Devon, 75 × 131⁄4 ft, with a 15-ft bole (1968); Killerton, Devon, 79 × 171⁄4 ft at 4 ft, and 92 × 14 ft, with a 10-ft bole (1970). But the most remarkable specimen in the British Isles grows at Westbury Court, Glos.; although only 45 ft high it is 241⁄2 ft in girth at 31⁄2 ft and has a spread of 96 ft from west to east and 77 ft from north to south (1973).
var. ballota (Desf.) A.DC. Q. ballota Desf.; Q. rotundifolia Lam. – A variety from the southern part of the Iberian peninsula and N. Africa, sometimes treated as a distinct species. It has large, sweet acorns which are roasted as sweet chestnuts are. It is, or was, even grown in orchards in S. Spain and propagated by grafting. It is to its acorns that it owes such distinctness as it possesses. The leaves are mostly oblong, rounded at both ends, with a mucronate tip, 1⁄2 to 2 in. long, grey beneath as in the holm oak. Sometimes they are roundish. It is neither so hardy nor so handsome as the common holm oak, and does not fruit freely in this country. It has been confused with round-leaved forms of Q. ilex. See also Q. gramuntia below.
cv. ‘Crispa’. – A curious form with small orbicular leaves, averaging about 1⁄2 in. in length, the margins decurved. Very slow-growing, and a curiosity merely; known in gardens since the early 19th century.
cv. ‘Fordii’. – Leaves of a peculiarly dark glossy green, narrow, 1 to 21⁄2 in. long, 3⁄8 to 5⁄8 in. wide, the margins wavy and more or less toothed. Of narrow habit. Raised in Lucombe and Pince’s Nursery at Exeter. Described in 1843.
cv. ‘Genabii’. – Leaves very large and leathery, as much as 5 in. long by 21⁄2 in. wide, coarsely toothed towards the apex. Distributed by Smith’s Nursery, Worcester, before1870.
var. gramuntia. – See note on Q. gramuntia below.
cv. ‘Latifolia’. – A large-leaved form like ‘Genabii’, the leaves of about the same size, but not so thick and rigid, toothed towards the apex.
cv. ‘Rotundifolia’. – Leaves broad-elliptic to almost orbicular. There is an example at Kew at the eastern end of the Syon Vista. Not to be confused with Q. ilex var. ballota, which is treated in some works under the name Q. ilex var. rotundifolia.
Q. gramuntia L., emend. Sm. Q. ilex var. gramuntia (L.) Loud. – The name Q. gramuntia, published by Linnaeus in the first edition of his Species Plantarum (1753) is taken from Magnol’s diagnosis of an oak discovered in the woods of the Gramont estate near Montpelier, in the 17th century: ‘Ilex fol. rotundioribus et spinosis e luco gramuntio’ (Magnol, Botanicum Monspeliense (1676), p. 140). Sir James Smith, who purchased the Linnaean herbarium, in which Magnol’s specimen is still preserved, noted that Linnaeus’ own description was evidently drawn from another Magnol specimen which does not differ from Q. ilex. To remedy the confusion he provided an amended description made from a tree, apparently a cultivated one, which in his view agreed with the specimen from the Gramont woods (Rees’ Cyclopaedia, Vol. 29 (1819), Qu. 30). As described by Smith, Q. gramuntia is a small, straggly tree with very short-stalked, almost orbicular, leaves barely 1 in. wide, edged with strong, divaricating spinous teeth, dark green above, densely woolly beneath. Fruits not described.
At one time a tree was in cultivation at Kew which resembled Q. gramuntia sensu Sir James Smith, and was certainly very distinct from normal Q. ilex. But that species is a polymorphic one, of which countless minor fluctuations have been described and named, and there can be little doubt that the Gramont tree was one of these. Later botanists searched for it in the woods there and found nothing but common Q. ilex. Of the many variants enumerated by Mme Camus the one that comes nearest to the Gramont tree was found in the département of Var in S.E. France, and was named var. spinifolia Albert. Some oaks that have been grown as Q. gramuntia or Q. ilex var. gramuntia are Q. ilex var. ballota.