Family: Pinaceae
Common Name: Pine

This well-known conifer group comprises over 100 species. Except for one species, which can be found as far south as Indonesia, they are native to the northern hemisphere. The pines are renowned for their commercial uses, in particular the production of timber and paper, while the resin of some species yields turpentine. The needles are used as mulch and the cones and bark for fuel. Although regarded as trees of far northern regions, such as Canada or Scandinavia, the greatest number of species is found in warm temperate and subtropical parts of North America.

The bristlecone pine (P. aristata, from the Rocky Mountains, has some of the oldest known specimens in the world. Over 6000 annual rings have been counted on contorted specimens of this species, growing on windswept mountain tops. Also in the United States is the tallest known species, P. lambertiana, which has been known to reach over 80 m (260 ft). Pine leaves or 'needles' are borne on short shoots in a fixed number, this being one of the most distinctive, identifying characteristics of Pinus. The number relevant to each species is noted below.

Most pines are two- to five-needled and rarely one. In some species, there can be a variation in number. Full maturity of cones and seeds is achieved over many months, so that at any time of year, three successive stages of seed-cone development can be seen along the branches. Pines are often grown for special purposes, such as screens, wind-breaks, timber production and Christmas trees. There are some highly ornamental species, although most are reasonably attractive. There is a species of pine to suit almost every climate, from the tropics to very cold zones.

Species

P. bungeana, lacebark pine, zone 5, from central China, is a slow grower but capable of reaching over 15 m (50 ft) in ideal conditions. It is prized for its flaky bark which sheds in patches to reveal a pure white trunk. It has short, stiff, shiny, green needles in groups of three, and shiny, gray twigs. The small, rounded cones are pale brown in colour.

P. canariensis, Canary Island pine, zone 9, grows up to 30 m (100 ft) tall. It has a very straight trunk, with dull reddish brown bark, broken into large plates. The very fine, straight, dull green needles, 25 cm (10 in) long, are borne in threes, and the brown cones are oval shaped.

P. contorta, shore pine or lodgepole pine, zone 7, from western United States, Canada and Alaska, is best suited to cool climates. It is a pyramidal 'Christmas tree' type, with a long central leader and densely packed, short, twisted needles, in twos.

P. coulteri, big-cone pine, zone 7, from the mountains of California and Mexico, is known for its huge cones, which grow to 35 cm (14 in) long and 15 cm (6 in) wide. It is a broad-crowned, heavy-branched tree, with stiff, blueish green needles in threes.

P. densiflora, Japanese red pine, zone 5, is often used in bonsai in Japan. Generally it is a medium-sized pine with soft, twisted needles like those of P. radiata, normally borne in twos. This lovely tree has attractive, orange-red, flaking bark and egg-shaped, yellow-purplish cones. It is suitable for cool areas with high rainfall.

P. elliottii, slash pine, zone 8, from the south-east of the United States, is useful for warmer, summer-rainfall areas. It makes a fine tree, with deeply furrowed, red-brown bark on its straight trunk and densely packed, straight needles, to 25 cm (10 in) long, in bundles of two or three. This species is used for screens and windbreaks, as well as for avenues, in warm climates. It is also grown for its timber.

P. halepensis, Aleppo pine, zone 8, from the eastern Mediterranean, tolerates most conditions and is a good choice for dry areas. Generally, it grows to less than 10 m (33 ft) high, sometimes forming a large shrub. Young trees are a broad, pyramidal shape, becoming more rounded with maturity. It has fine, straight, dull green needles, to 10 cm (4 in) long, in pairs. This species has attractive, red-dish brown, scaly bark, while the young shoots are gray-green in colour. The egg-shaped cones are reddish brown.

P. lambertiana, sugar pine, zone 7, from Oregon and California, is a very handsome pine with a very tall, straight, slender, smooth, gray trunk. The needles are borne in bundles of five and are around 10 cm (4 in) long. The slightly curved cones are unusual, growing up to 45 cm (18 in) long, with thin, rounded, overlapping scales. This is one of the 'white pine' group, all of which make fine ornamentals but require good soil and prefer cool climates with high rainfall.

P. montezumae, zone 6, from Mexico, is a variable species which has been divided into a number of varieties. The fine needles, 15-25 cm (6-10 in) long, are generally in bundles of five, but occasionally they may be in bundles of four to six. They are blue-green or gray-green, and variable in habit. This species is suitable for a wide range of temperate and subtropical climates.

P. monticola, western white pine, zone 6, from south-west Canada and western United States, is related to and rather like P. lambertiana, differing mainly in the size of its cones, which are much smaller. As a young tree it is quite lovely, its needles, borne in bundles of five, being shiny, dark green on the outer face with bands of bright blueish white on the two inner faces. In its habitat, this tree can reach heights of 65 m (215 ft).

P. mugo, dwarf mountain pine, zone 3, from central and southern Europe, one of the few naturally dwarf pines, may be a spreading shrub or a small tree, preferring a cool temperate climate. The branch tips point upward and the stiff, curved, olive green needles are borne in pairs, in dense rosettes. Its windswept appearance makes it an appealing bonsai subject. This species and some of the more compact cultivars and wild forms also make good rockery plants. The Pumilio Group is often a semi-prostrate mound of closely packed needles, though it can grow to 2 m (6 ft). Cultivar 'Gnom' has a rounded, compact habit, rarely exceeding 1 m (3 ft) in height.

P. nigra, black pine, zone 5, from central and southern Europe, has an open, conical habit, rarely exceeding 15 m (50 ft) in cultivation. It has a straight trunk, dark, furrowed bark and stiff, twisted, dark gray-green needles, in pairs, 10-15 cm (4-6 in) long.

P. palustris, long-leaf or pitch pine, zone 7, from the south-east of the United States, is regarded as a most useful timber tree. Adult trees are similar to P. elliottii but they have heavier, more twisted limbs. The young plants are distinctive as they pass through a stemless, tufted stage for the first five to ten years, with the growing point at or below ground-level, and densely crowded, floppy needles, up to 40 cm (16 in) long. The stem then elongates, but stays unbranched for a height of up to 4 m (13 ft) or more, the seedling tree appearing as a straight pole, clothed in long, soft, bright green needles. This species does well in swampy areas, though it requires a long, hot, humid summer to make good growth. It is not widely cultivated, due to slow early development.

P. patula, Mexican weeping pine, zone 8, is known mainly as an ornamental in the US. Probably the most elegant pine, it is a vigorous, broadly pyramidal tree, usually 10-15 m (33-50 ft) tall, with fine, soft, mid-green needles drooping from the branches. Needles grow in threes to about 20 cm (8 in) long. This species does well in warm temperate areas, though it tolerates cold conditions.

P. pinaster, maritime pine, zone 8, from south-west Europe and the Mediterranean, can grow up to 25 m (80 ft) tall in cultivation. It is an important source of turpentine. The maritime pine has a short, often slightly crooked trunk and a rounded crown. Its attractive, reddish brown, fissured bark, with its jigsaw pattern, is very distinctive. The curved, twisted, shiny, gray-green needles, 10-20 cm (4-8 in) long, are borne in pairs. Suitable for exposed sites, this species does well in sandy, gravelly or hard clay soils of relatively low fertility. On such sites, especially near the sea, it makes a stunted, crooked, often very striking, small tree.

P. pinea, stone pine or Roman pine, zone 8, from southern Europe and Turkey, was considered the 'true' pine in Roman times, grown for its edible seeds, or pine nuts, as opposed to P. pinaster, the wild or 'false' pine. It has a characteristic growth habit, growing only 15-20 m (50-65 ft) tall, with a straight, often leaning trunk and a flat, umbrella-like crown of dense, deep green foliage. The slightly twisted needles, about 10 cm (4 in) long, are borne in pairs, and the abundant, rounded cones, 10-15 cm (4-6 in) long, have very thick, woody, brown scales. Its climatic preferences are similar to those of the cluster pine, but it is not quite so tolerant of poor soils.

P. ponderosa, western yellow pine, zone 6, is a native of western North America, where it is valued for its timber. It can grow up to 70 m (230 ft) tall in its habitat, but is generally much smaller in cultivation. It is quite slender and upright, with an open habit. Its distinctive bark forms a mosaic of different-coloured plates. The stiff, straight, pale green leaves are borne in threes and are 15-25 cm (6-10 in) long. Preferring heavy soils, this species does well in cooler areas.

P. radiata, Monterey pine, zone 7, is a native of California, where it makes a rather crooked tree of only moderate size. However, in some forest plantations it has been known to reach heights of over 50 m (160 ft) and diameters of 1 m (3 ft) or more. Ibis species is distinguished from most other pines by the rich, dark green foliage shade, the furrowed, gray bark and the rather soft, twisted needles, 7-10 cm (3-4 in) long, in groups of three. It is a particularly good pine for coastal planting.

P. roxburghii (Synonym: P. longifolia), Chir or longleafed Indian pine, zone 9, is very similar to its relative, P. canariensis, differing mainly in its slightly more spreading, roundtopped habit and the richer red colour of its bark. It has light green, drooping needles, to 30 cm (12 in) long, which grow in bundles of three, and oval cones with reflexed scales. This is a beautiful Himalayan species, its range extending from Afghanistan to Bhutan, but sadly, it is not often grown, possibly because it needs a warm climate.

P. thunbergii, Japanese black pine, zone 6, is similar to P. radiata, but it has stiffer, slightly thicker and deeper grayish green needles, borne in pairs. Its irregular branches and purplish black bark, and its capacity to stand trimming and pruning, have made it an important bonsai subject in Japan. It does well in sandy soils and in coastal conditions in cooler climates.

Cultivation

As the various species of pine originate from a vast range of climates and habitats, their requirements in cultivation vary widely. However, most like full sun, the only exception being where a species is grown in a hotter or drier climate than it has adapted to. In such instances, partial shading is advisable, as this provides cooler conditions and humidity.

Propagate from seed sown at any time of year in mild climates, or in spring in areas with cold winters. Use a light, sandy germinating medium, barely cover the seeds, and place in a warm, shady position. Germination mostly occurs very rapidly. Pot seedlings into open-bottomed tubes or black polythene bags to avoid coiling of the roots. If large numbers of trees are required, plant seedlings in rows in a well-tilled plot of soil and transplant bare-rooted to their permanent positions when about 20-30 cm (8-12 in) high. Bare-rooted planting is normally done in winter and should only be used in regions with cool, wet winters. Container-grown plants can be planted out at any time, but preferably from winter to early spring.

Watering is generally unnecessary, unless pines are established under very harsh conditions, as their roots rapidly penetrate to the subsoil. Staking of young trees is rarely required. Pines generally respond well to feeding, superphosphate giving good results where soils are deficient in phosphorus. Pruning is not normally required for these symmetrical trees; however, twin leading shoots should be reduced to a single growth to avoid a weak point in the long term.

Climate

Choose a pine to suit your area.