A tree ordinarily 40 to 50 ft, sometimes 80 ft high, often branching low and acquiring a spreading round-topped shape when old; old bark rough, with a distinct reddish tinge. Young shoots glabrous, rather glaucous at first, becoming scaly and reddish brown. Winter-buds not resinous, 1⁄2 to 3⁄4 in. long, cylindrical, covered with awl-shaped, pointed, fringed, brown scales which are free except at the base and slightly spreading. Leaves pendulous, normally in threes (occasionally in four or fives), 6 to 9 in. long, very slender, and very minutely toothed on the margins, persisting two to four years; basal sheath persistent, about 1 in. long. Cones shortly stalked, often in clusters of two to five, 21⁄2 to 4 in. long, 11⁄4 to 11⁄2 in. wide at the base; tapering upwards, curved, unequally sided at the base, pale shining brown.
Native of Mexico; discovered in 1828 and introduced then or soon after, as a plant 6 ft high is recorded by Loudon to have been growing in the garden of A. B. Lambert in 1837. It must be accounted one of the rather tender pines, and it is found at its best in Cornwall and similar places. This pine is unmistakable in its very slender, drooping leaves in bundles of threes with a persistent leaf-sheath. Very attractive and distinct for mild districts, it may also be tried in cooler places.
P. patula is uncommon in southern England, but there is a specimen in the Pinetum at Wakehurst Place, Sussex, planted around 1918, which measures 46 × 31⁄2 + 3 ft (1971). A small tree, about twenty years planted, is growing well in the nursery of Messrs Hillier at Jermyns House, Romsey. But most of the recorded trees are in the south-west and in Ireland. The most notable of these are: Tregothnan, Cornwall, 57 × 71⁄2 ft (1971); Tregrehan, Cornwall, 52 × 51⁄2 ft (1971); Fota, Co. Cork, Eire, 54 × 61⁄2 ft (1966); Powerscourt, Co. Wicklow, Eire, 54 × 51⁄4 ft (1966); Shelton Abbey, in the same county, 52 × 51⁄4 ft (1966).
P. greggii Engelm. P. patula var. macrocarpa Mast. – This pine from N.E. Mexico is closely akin to P. patula but less ornamental. Leaves in threes, bright green, shorter and not so pendulous. Cones like those of P. patula, but tawny yellow. The bark is very different, smooth and grey on young trees, grey and fissured on older trees. The tree at Leonardslee in Sussex mentioned in previous editions still exists and measures 47 × 6 ft (1962). In the National Pinetum at Bedgebury in Kent was a tree measuring 53 × 51⁄2 ft (1970) which grew originally in the Temperate House at Kew and was moved to Bedgebury in 1926. It died in 1973.