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american and indian pines

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american and indian pines - American and Indian Pines
american and indian pines - A large number of Pine species are found on the North American continent, but most are local forms adapted to local geographical conditions, which vary widely over so large an area, and seldom approach those prevailing in western Europe. The Pines of the high latitudes of Canada are as unlikely to succeed with us, as are those of the high altitudes of the Rockies. Those of the southern states are too tender for Britain, whilst those of the north-east apparently find our climate too humid and lacking in distinct changes of season. But the species from the western or Pacific coast are usually able to thrive under British forest conditions.

India is not often thought of as the home of the pine tree, but several species are of great economic importance along the Himalayan slopes, and one of these is widely grown in Britain as an ornamental tree.

The Lodge-pole Pines (Pinus contorta, Douglas, and var. murrayana, Engel.) of the Pacific sea-board are two-needled pines closely resembling the Mountain Pines of Europe. Their chief points of difference lie in the colour of the needles, which are bright or yellowish green, the tendency of these needles to make a slight twist (less so than the Corsican Pine), and the usually twisted habit of growth. The shoots are normally more or less contorted, though they ultimately grow-into a straight tree. As with the Mountain Pines, dwarf and tall forms are known. The dwarf form from the barren soils of the windswept Pacific coast is sometimes planted in Britain as the first line of a wind-break. The tall form, var. Murrayana, is the true Lodgepole Pine of the mountains farther inland, so called from its use by the Indians to support their tents; this has been planted as a timber tree in Britain, and may be expected to behave in much the same way as Scots Pine. As it comes from a region of high rainfall, it will stand moister climatic conditions than Scots Pine, but on the other hand may be liable to suffer from drought. The timber of Lodgepole Pine is not durable, but is suitable for general carpentry and constructional work. It is little valued in its native land owing to the great quantities of more durable timbers readily available in that region. As more valuable timbers are cut out, with little regard to future regeneration, the Lodgepole Pine seeds up the clearings and replaces them.

The Canadian jack pine (Pinus banksiana, Lambert), another two-needled species, resembles the Lodgepole Pines in its twisted branches, but the needles are straight and very short. It has been introduced from northern Canada for planting in cold exposed soils in Britain, but is unlikely to be at home here as our summer is cooler, with less intense sunlight, than is the brilliant summer of the sub-arctic zone where the tree is native. It never becomes a tall tree, and in Canada the wood is chiefly used for paper pulp or firewood.

The Monterey Pine (Pinus radiata, D. Don, syn. Pinus insignis) is a remarkable tree having the distinction of growing faster than any other in those parts of the country which are mild enough to permit it to thrive. When it was discovered on the coast of California about 1830, its natural range was so limited that, it was verging upon extinction. The wild trees were more notable for their rugged picturesque form than for any apparent timber value, but when transported to the southern hemisphere it speedily became important as an extremely rapid producer of light, soft timber for which there is always a steady demand, particularly for box-making.

The needles of the Monterey Pine are grouped in threes, in dense tufts, and are a vivid emerald green in colour, much lighter and brighter than those of other pines. The bark is smooth on branches, rugged on the bole; and the side-branches are strongly developed. The cones are large and asymmetrical. Monterey Pine is readily raised from seed, but is not easy to transplant and should go out to the forest at the one-year-one-year or two-year-one-year stage. It will only thrive on open, dry sites in the south and west, and needs a good well-drained loamy or sandy soil. It is extremely wind- firm and resists salt-laden winds off the sea, forming an excellent, quick-growing wind-break, and keeping its foliage well even close to the ground.. A height-growth of 3 feet a year may be expected, but the maximum height of the tree seldom exceeds 100 feet. The timber of ornamental and exposed trees is too knotty and coarse to be of value, and the employment of Monterey Pine in forest planting is restricted by the limited extent of sites which suit it. Figs. 1, 2b.

The Bull Pine (Pinusponderosa, Douglas) or Western Yellow Pine, is another three-needled species sometimes planted in Britain. It is readily distinguished from the Monterey Pine by the blue-green colour of the needles. In its native country it attains a great size, reaching 200 feet or more in height, and is greatly valued for its strong and resinous timber. As most conifers from its homeland, British Columbia, thrive in our climate, it may prove a useful addition to the somewhat limited list of forest pines suitable for Britain.

The Pitch Pine (Pinus palustris, Miller), Long Leaf Pine. This is a three-leaved species found along the eastern sea-board of North America; allied species extend farther inland. It has been introduced into Britain, but does not stand our climate. Its timber is both strong and durable, widely used in its native country, and exported in quantity to Europe. The growing trees are tapped for resin, and waste wood is valued for fuel. The long needles are a distinguishing feature.

The Northern Pitch Pine (P. rigida, Miller), G. Pechkiefer, has been extensively planted in Germany, but its timber is inferior to P. palustris.

The Weymouth Pine {Pinus strobus, L.). G. Weymouthsföhre; F. Pin du Lord; White Pine. Named after Lord Weymouth, who popularised its cultivation in Britain about the year 1710. This is a five-needled pine, distinguished by its somewhat hairy shoots its cones are distinctive, being of the size and shape of a banana, about 6 inches long, narrow, with widely-spaced scales. It is native to north-eastern America, where it attains great size, over 200 feet, and formerly fonried vast forests, now much reduced by fellings. Its timber is highly valued, being light in weight, of smooth even grain, not liable to shrink when seasoned, and therefore of particular value in pattern making for engineering work. Its colour is also attractive - pale reddish brown heartwood, with a thin zone of pale yellow sapwood, fitting it for fine interior work and furniture making. It is not durable out of doors. The timber is widely used for constructional work of all kinds in eastern North America, and has been exported in big quantities to Europe.

Although the Weymouth Pine has been grown in Britain for two centuries, it has made but little headway as a plantation tree. In our climate it suffers severely from an Aphid attack (Chermes), the minute insects infesting the bark being covered in a white felty down. Its fungal pests are numerous, in particular the Honey Fungus (Agaricus, syn. Armillaria), and a rust disease (Cronartium). This latter requires as an intermediate host, broad-leaved shrubs of the Blackcurrant tribe (Ribes), and is therefore most severe near orchards and gardens. As a result, although it is readily propagated and grows quickly in youth, a high-yielding plantation is rarely found; on the continent of Europe it grows somewhat better but is seldom really satisfactory. As a park tree, Weymouth Pine is valued for its dense foliage of slender blue green needles, and its well-proportioned thin-barked trunk, but specimen trees seldom present a really healthy appearance. Fig. 3.

There are two possible ways in which a valuable timber tree, with these failings, might be made to form a part of our true forest flora. Either a special immune strain suited to this climate might be selected and isolated, or an allied pine with the same qualities might be introduced and planted instead. It is clearly out of the question to combat the various pests and diseases on a forest scale throughout the lifetime of the tree, and therefore a form less susceptible to them must be grown instead. A possibility in this instance is the Macedonian Pine (P. peuke), which already grows under climatic conditions more nearly resembling our own.

The Mountain White Pine (Pinus monticola, Don), G. Gebirgstrobe, is a western form of P. strobus, found from the Pacific coast to the heights of the Rocky Mountains. It has been introduced into Britain in the hope of its thriving better with us than P. strobus, from which species it is distinguished only by stiffer leaves and more downy brown-haired shoots. As regards immunity from disease, results so far are not outstanding, possibly because the seed used to raise the trees has been collected at too high an altitude in the mountains; only the coastal forms may be expected to thrive at the low levels where plantations are made in Britain.

The Sugar Pine (Pinus lambertiana, Douglas), G. Zuckerföhre, is another five-needled pine found in California, distinguished by stiff, pointed, spirally ranged needles, enormous cones over a foot long, and a sugary exudation from its wood. It attains enormous size and is an important timber producer. Artificial propagation is difficult, as cones are borne high on the tree, and the seed fells as soon as ripe. As it descends to within 2,000 feet of sea-level, in Oregon, it may prove hardy in Britain.

The Bhotan Pine or Blue Pine (Pinus excelsa, Wallich), G. Himalajastrobe, is an Indian five-needled pine resembling P. strobus, from which it is distinguished by its smoother, bluish shoots, and smooth cones. Its timber is important in the Himalayan region, where it is also of value as a resin producer. It thrives as a decorative tree in Britain, and as it comes from the same climatic region as the Deodar, might succeed here under forest conditions. Fig. 2c.

The Chir (Pinus longifolia, Roxburgh), G. Emodikiefer, a three- needled long-leaved species, is another important Indian timber, resin, charcoal, and tar producer. As it grows at lower altitudes than P. excelsa, is requires a warmer climate and cannot succeed out of doors in Britain, but has been introduced with success to South Africa. Young plants were at one time cultivated in British greenhouses, for the beauty of their foliage - a somewhat strange use for a giant tree of the Himalayas.

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