High districts covered with oaks and chestnuts succeed to this almost tropical vegetation; a little higher up and we reach the elevated regions of the Pollino and the Sila, covered with firs and pines, and affording rich pastures even in the midst of summer, when heavy dews and light frosts succeed each other in July and August, and snow begins to appear at the end of September or early in October.
Witches-brooms are the tufted bunches of twigs found on silver firs, birches and other trees, and often present resemblances to birds nests or clumps of mistletoe if only seen from a distance.
It is the common result of fires passing alongtoo rapidly to burn the trees; and thin-barked treeshornbeam, beech, firs, &c. may exhibit it as the results of sunburn, especially when exposed to the south-west after the removal of shelter.
The dominant characteristics of the arboreous vegetation are, besides deciduous and amentiferous trees, Coniferae, especially the - more recent tribe of Abietineaepines, silver-firs, hemlocks, spruces, ~,,,1 ~ of which.
FIR, the Scandinavian name originally given to the Scotch pine (Pinus sylvestris), but at present not infrequently employed as a general term for the whole of the true conifers (Abietineae); in a more exact sense, it has been transferred to the "spruce" and "silver firs," the genera Picea and A bies of most modern botanists.
The firs are distinguished from the pines and larches by having their needle-like leaves placed singly on the shoots, instead of growing in clusters from a sheath on a dwarf branch.
In the spruce firs (Picea), the cones are pendent when mature and their scales persistent; the leaves are arranged all round the shoots, though the lower ones are sometimes directed laterally.
In the genus Abies, the silver firs, the cones are erect, and their scales drop off when the seed ripens; the leaves spread in distinct rows on each side of the shoot.
The most important of the firs, in an economic sense, is the Norway spruce (Picea excelsa), so well known in British plantations, though rarely attaining there the gigantic height and grandeur of form it often displays in its native woods.
Numerous other firs are common in gardens and shrubberies, and some furnish valuable products in their native countries; but they are not yet of sufficient economic or general interest to demand mention here.
It may here be remarked that the name "European frankincense" is applied to Pinus Taeda, and to the resinous exudation ("Burgundy pitch") of the Norwegian spruce firs (Abies excelsa).
Firs and pines cover the mountain heights; and below these, but still at an elevation of eight or nine thousand feet, is a zone of vegetation, consisting principally of oaks and rhododendrons.
SEQUOIA, a genus of conifers, allied to Taxodium and Cryptomeria, forming one of several surviving links between the firs and the cypresses.
Of Chalcis, rises the highest of its mountains, Dirphysor Dirphe,now Mount Delphi (5725 ft.),the bare summit of which is not entirely free from snow till the end of May, while its sides are clothed with pines and firs, and lower down with chestnuts and planes.
The members of the genus Larix are distinguished from the firs, with which they were formerly placed, by their deciduous leaves, scattered singly, as in Abies, on the young shoots of the season, but on all older branchlets growing in whorl-like tufts, each surrounding the extremity of a rudimentary or abortive branch; they differ from cedars (Cedrus), which also have the fascicles of leaves on arrested branchlets, not only in the deciduous leaves, but in the cones, the scales of which are thinner towards the apex, and are persistent, remaining attached long after the seeds are discharged.
When standing in an open space, the larch grows of a nearly conical shape, with the lower branches almost reaching the ground, while those above gradually diminish in length towards the top of the trunk, presenting a very symmetrical form; but in dense woods the lower parts become bare of foliage, as with the firs under similar circumstances.
The larch, from its lofty straight trunk and the high quality of its wood, is one of the most important of coniferous trees; its growth is extremely rapid, the stem attaining a large size in from sixty to eighty years, while the tree yields good useful timber at forty or fifty; it forms firm heartwood at an early age, and the sapwood is less perishable than that of the firs, rendering it more valuable in the young state.
It is far more durable than any of the oaks of that region, is heavy and close-grained, and much stronger, as well as more lasting, than that of the pines and firs of Canada.
Directing a river so that it may deposit its sedimentary matter in the lower-lying parts, thus levelling them up and consolidating them, and then leading the water away again by drainage; (iii.) the planting of firs and eucalyptus trees, e.g.
A temperate or colder zones where a season favourable to vegetation is succeeded by an unfavourable or winter season, leaves of evergreens must be protected from the frost and cold drying winds, and are therefore tougher or more leathery in texture than those of deciduous trees, and frequently, as in pines, firs and other conifers, are needle-like, thus exposing a much smaller surface to the drying action of cold winds.
The form of the leaf shows a very great variety ranging from the narrow linear form with parallel sides, as in grasses or the needle-like leaves of pines and firs to more or less rounded or orbicular - descriptions of these will be found in works on descriptive botany - FIG.
The mountain forests consist chiefly of firs, Free Towns pines and larches, but contain Lbeck also silver firs, beeches and Bremen oaks.
A proportionally large importation of timber is caused by the scarcity of native timber suitable for building purposes, the plantations of firs and pines being insufficient to produce the quantity required, and the quality of the wood being inferior beyond the age of about forty years.
Above this belt the firs gradually disappear and are succeeded by the shortleaved Pinus montezumae, or Mexican " ocote " - one of the largest species of pine in the republic. These continue to the upper tree-line, accompanied by red and purple Pentstemon and light blue lupins in the open spaces, some ferns, and occasional masses of alpine flowers.
The white fir, or Norway spruce (Abies excelsa), is exported fro Russia, Sweden and Norway, where it grows in enormous quantit It is the tallest and straightest of European firs, growing with a slender trunk to a height of from 80 to 100 ft.
In this belt and the following one of firs the big tree also grows.
Above the firs come the tamarack, constituting the bulk of the lower Alpine forest; the hardy long-lived mountain pine; the red cedar or juniper, growing even on the baldest rocks; the beautiful hemlock spruce; the still higher white pine, nut pine, needle pine; and finally, at io,000 to 12,000 ft., the dwarf pine, which grows in a tangle on the earth over which one walks, and may not show for a century's growth more than a foot of height or an inch of girth.
The ridges which ramify from the Paramera are covered with valuable forests of beeches, oaks and firs, presenting a striking contrast to the bare peaks of the Sierra de Gredos.
7rLru), a name given by the ancients to some of the resinous cone-bearing trees to which it is now applied, and, as limited by modern botanists, the designation of a large genus of true conifers, differing from the firs in their hard woody cone-scales being thickened at the apex, and in their slender needle - shaped leaves growing from a membranous sheath, either in pairs or from three to five together - each tuft representing an abortive branch, springing from the axil of a partially deciduous scale-leaf, the base of which remains closely adherent to the stem.
Vast numbers of Scotch firs are raised in nurseries for artificial planting; the seed is sown in the spring, being just covered with earth, and the seedlings transplanted in the second year into rows for further culture, or taken direct from the seed-bed for final planting; sometimes the seed is sown where the trees are intended to grow.
There are firs and spruces on the mountains, characteristic of the Boreal zone; pines characteristic of the Transition zone; pinon juniper, greasewood and the universally conspicuous sage-brush, characteristic of the Upper Sonoran zone.
On the mountains the trees are chiefly pines, firs, spruce and hemlock.
Thus, the cones of firs and the stroboli of the hop are composed of a series of spirally arranged bracts covering fertile flowers; and the scales on the fruit of the pine-apple are of the same nature.
Above this belt of mahogany, pines and firs are sometimes found.
Oaks, elms, firs, ashes and beeches are the principal forest trees.
The best known and by far the largest division of the Gymnosperms is that of the cone-bearing trees (pines, firs, cedars, larches, &c.), which play a prominent part in the vegetation of the present day, especially in the higher latitudes of the northern hemisphere; certain members of this class are of considerable antiquity, but the conifers as a whole are still vigorous and show but little sign of decadence.
Excelsa, the Norfolk Island pine, many pines and firs, cedars and other genera illustrate the pyramidal form.
These projections and ridges may be homologous with the seminiferous scale of the pines, firs, cedars, &c. The simplest interpretation of the cone of the Abietineae is that which regards it as a flower consisting of an axis bearing several open carpels, which in the adult cone may be very small or large and prominent, the scale bearing the ovules being regarded as a placental outgrowth from the flat and open carpel.
The hills are almost everywhere well wooded, the predominant trees being firs and beeches.
Danish peat-mosses again show the existence of man at a time when the Scotch fir was abundant; at a later period the firs were succeeded by oaks, which have again been almost superseded by beeches, a succession of changes which indicate a considerable lapse of time.
The commonest firs are Abies nordmannia and A.
Ou preuves de l'existence du firs de Louis XV I.