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Key to Species — Part 1

A. Leaves 5 in a bundle.

B. Cones long stemmed; scales thin; leaves 3 to 4 inches long.

C. Leaves slender, flexible; cones 5 to 8 inches long.

D. Cone scales not recurved at maturity; leaves bluish green. (P. Strobus) WHITE PINE

DD. Cone scales recurved at maturity; leaves pale green. (P. strobiformis) ARIZONA WHITE PINE

CC. Leaves stout, stiff.

D. Cones 5 to 12 inches long; limbs grey.

(P. monticola) MOUNTAIN PINE

DD. Cones 12 to 18 inches long; limbs green.

(P. Lambertiana) SUGAR PINE

BB. Cones short stemmed; scales thick; leaves 1 to 2 inches long.

C. Leaf bundles scattered; cones 3 to 10 inches long, opening at maturity.

(P. flexilis) ROCKY MOUNTAIN WHITE PINE

CC. Leaf bundles in crowded clusters.

D. Leaf clusters. at ends of twigs; cones not opening; bark pale.

(P. albicaulis) WHITE-BARK PINE

DD. Leaf clusters along sides of twig; cone scales with spiny beaks.

E. Spines of cone scales minute, incurved.

(P. Balfouriana) FOXTAIL PINE

EE. Spines of cone scales, long, slender.

(P. aristata) BRISTLE-CONE PINE

AA. Leaves 1 to 4 in a bundle, 1 to 2 inches long; cones globose; seeds nut-like.

B. Bundles 4-leaved, pale, glaucous green.

(P. quadrifolia) NUT PINE

BB. Bundles 2 to 3-leaved, dark green.

C. Leaves slender. (P. cembroides) NUT PINE

CC. Leaves stout. (P. edulis) NUT PINE

BBB. Bundles 1-leaved, pale, glaucous green.

(P. monophylla) NUT PINE

White Pine (Pinus Strobus, Linn.)--A stately tree, 100 to 120 feet high, conical, with spreading, horizontal branches in whorls of five. Bark grey, furrowed, thick, with broad, scaly ridges. Wood light, soft, close grained, resinous, easily worked. Buds, a strong, terminal, set round by five lateral ones in whorl; 1/4 to 1/2 inch long, pointed, with thin, pale-brown scales. Leaves evergreen, needle-like, in fives, sheathed at base of bundle, 3 to 5 inches long, slender, 3-sided, flexible, blue-green. Flowers in June, monoecious; staminate, clustered at base of season's shoots, 2/3 to 1 inch long, catkin-like, yellowish; pistillate, subterminal, single or in twos, stemmed, elliptical, pink or purplish, and scaly, 2 ovules on each scale. Fruit biennial, 5 to 10 inches long, slender, stalked, with thin, unarmed scales; seeds winged. Preferred habitat, good soil, moist woodlands, or uplands. Distribution, Newfoundland to Manitoba; south through lowa, Illinois and Ohio to northern Georgia; southern Canada and Eastern States, along Alleghanies to eastern Kentucky and Tennessee. Uses: One of the best ornamental conifers and formerly the chief lumber tree in this country.

Pines bear their evergreen leaves in sheathed bundles set on little projecting shelves along the twigs. The sheaths are shed during the spring in all the white pines, and the number of leaves in a bundle is always five. Certain pitch pines have leaves in fives, but the sheaths will be found at the bases of the bundles throughout the season. These 5-leaved pitch pines are all Western trees. In Eastern woods a 5-leaved pine is a white pine, P. Strobus, whether it is a flourishing little sapling, with only three or four whorls of branches coming out from its central stem, or a great forest tree towering above its broad-leaved neighbours, noble and picturesque, though storms have destroyed the symmetry of its youth.

Stroke the leaves of a white-pine branch--they are soft and flexible. As they sway in the wind they are graceful and light; the tree seems decked with plumes of dark blue-green. The young shoots, pale yellowish green, lighten the sombre pine woods, and the clustering catkins, shaking out their abundant pollen, sift gold dust through the whole forest. The pistillate flowers show themselves clustered about the terminal bud, which keeps on growing, leaving them to ripen, through two seasons, into long, slender green cones. The pinkish purple of these tiny cone flowers adds a rich colour to the upper twigs, where they stand erect until autumn. Below them, hanging down with their weight, are the half-grown cones, slim, finger-like and green, with tight, smooth scales, that will turn brown and discharge their ripened seed at the end of their second summer.

This white pine of ours is built on a semi-decimal plan, which it is quite worth our while to notice. In the gracefully winged seed, that reminds us of the samara of a maple, there are ten cotyledons, or seed leaves, that mount the stem, and surround the precious terminal bud when the seed germinates. This bud is the "leader." If anything happens to it the central shaft is maimed for life, and either one side bud will have to bend upward and take the leader's place, or two will divide the honour, and a forked pine is the result.

The buds on the crown of a baby white pine cluster at the top--a circle of five around the central bud. In spring the leader grows upward, and at its base five branches radiate. Next year the crown repeats the same story, and the tips of the side branches divide and elongate in the same way. The best growth is generally made by the crown buds in the very top of the tree. So it happens that we may count the years of our sapling by the whorls of branches it bears. In the early years the growth is beautifully symmetrical, if there is room for sun and air to reach the little tree. Later the branches crowd each other, and some are killed. In deep woods where trees interfere, the stems are bare of living branches almost to the top.