WINTER KEY TO THE GENERAB

MANUAL OF TREES

DESCRIPTION OF SPECIES

WITH

SUMMER AND WINTER KEYS
TO THE SPECIES

GINKGOACEAE

GINKGOACEAE

Ginkgo.C Maidenhair Tree

Ginkgo biloba L. [Salisburia adiantifolia Smith]

HABIT.—A slender tree in youth, with slender, upright branches, becoming broader with age and forming a symmetrical, pyramidal crown; probably 60-80 feet high, with a trunk diameter of 2-4 feet.

LEAVES.—Clustered at the ends of short, spur-like shoots, or scattered alternately on the long terminal branches; simple; 2-5 inches broad; more or less fan-shaped; usually bilobed and irregularly crenate at the upper extremity; thin and leathery; glabrous, pale yellow-green on both sides; petioles long, slender; turning a clear, golden yellow before falling in autumn.

FLOWERS.—May, with the leaves; dioecious; the staminate in short-stalked, pendulous catkins, 1 to 1-1/2 inches long, yellow; the pistillate more or less erect on the shoot, long-stalked, consisting of 2 naked ovules, one of which usually aborts.

FRUIT.—Autumn; a more or less globose drupe, orange-yellow to green, about 1 inch in diameter, consisting of an acrid, foul-smelling pulp inclosing a smooth, whitish, somewhat flattened, almond-flavored nut.

WINTER-BUDS.—Terminal bud about 1/8 inch long, conical, smooth, light chestnut-brown; lateral buds divergent, usually only on rapid-growing shoots.

BARK.—Twigs gray-brown and smooth; thick, ash-gray and somewhat roughened on the trunk, becoming more or less fissured in old age.

WOOD.—Light, soft, weak, close-grained, yellow-white to light red-brown, with thin, lighter colored sapwood.

NOTES.—Origin in dispute, but probably a native of northern China. Extensively cultivated in China and Japan, where its fruit is esteemed. Easily propagated from seed. Thrives in deep, well-drained, rich soil. Practically free from insect and fungous attacks, and little harmed by the smoke of cities. Probably hardy throughout the southern half of the Lower Peninsula.

PINACEAE

SUMMER KEY TO THE SPECIES OF PINUS

WINTER KEY TO THE SPECIES OF PINUS

PINACEAE

White Pine

Pinus strobus L.

HABIT.—A large tree 60-80 feet high, with a trunk diameter of 2-4 feet; forming a wide, pyramidal crown. Formerly trees 100-150 feet in height and 5-7 feet in trunk diameter were not exceptional.

LEAVES.—In clusters of five; 3-5 inches long; slender, straight, needle-shaped, 3-sided, mucronate; pale blue-green. Persistent about 2 years.

FLOWERS.—June; monoecious; the staminate oval, light brown, about 1/3 inch long, surrounded by 6-8 involucral bracts; the pistillate cylindrical, about 1/4 inch long, pinkish purple, long-stalked.

FRUIT.—Autumn of second season, falling during the winter and succeeding spring; pendent, short-stalked, narrow-cylindrical, often curved, greenish cones, 4-10 inches long; scales rather loose, slightly thickened at the apex; seeds red-brown, 1/4 inch long, with wings 1 inch long.

WINTER-BUDS.—Oblong-ovoid, sharp-pointed, yellow-brown, 1/4-1/2 inch long.

BARK.—Twigs at first rusty-tomentose, later smooth and light brown, finally thin, smooth, greenish; thick, dark gray on the trunk, shallowly fissured into broad, scaly ridges.

WOOD.—Light, soft, weak, compact, straight-grained, easily worked, light brown, with thin, whitish sapwood.

DISTRIBUTION.—Upper Peninsula and Lower Peninsula north of Allegan, Eaton and St. Clair Counties. Often planted as an ornamental tree farther south.

HABITAT.—Prefers a light, fertile loam; sandy soils of granite origin.

NOTES.—Rapid of growth. Small seedlings easily transplanted. Formerly very abundant, but rapidly nearing extinction through destructive lumbering.

PINACEAE

Jack Pine. Scrub Pine

Pinus banksiana Lamb. [Pinus divaricata (Ait.) Du Mont de Cours.]

HABIT.—Usually a small tree 20-30 feet high, with a trunk diameter of 8-12 inches; forming a crown varying from open and symmetrical to scrubby, stunted, and variously distorted.

LEAVES.—In clusters of two; about 1 inch long; narrow-linear, with sharp-pointed apex; stout, curved or twisted, divergent from a short sheath; dark gray-green. Persistent 2-3 years.

FLOWERS.—May-June; monoecious; the staminate in oblong clusters 1/2 inch long, composed of many sessile, yellow anthers imbricated upon a central axis; the pistillate in subglobose clusters, composed of many carpel-like, purple scales (subtended by small bracts) spirally arranged upon a central axis.

FRUIT.—Autumn of second or third season, but remaining closed for several years and persistent on the tree for 10-15 years; erect, usually incurved, oblong-conical, sessile cones, 1-1/2-2 inches long; scales thickened at the apex; seeds triangular, nearly black, 3/8 inch long, with wings 1/3 inch long.

WINTER-BUDS.—Terminal bud 1/4 inch long, ovoid, rounded, pale brown; lateral buds smaller.

BARK.—Twigs yellow-green, becoming purple, finally dark red-brown and rough with the persistent bases of fallen leaves; thin, dark red-brown on the trunk, with shallow, rounded ridges, rough-scaly on the surface.

WOOD.—Light, soft, weak, close-grained, light brown, with thick, whitish sapwood.

DISTRIBUTION.—Common from Clare County northward; occurs sparingly along the lake shore as far south as Grand Haven on the west and Port Austin on the east.

HABITAT—Sandy, sterile soil.

NOTES.—Cones open unevenly. Slow of growth. Difficult to transplant.

PINACEAE

Austrian Pine. Black Pine

Pinus laricio austriaca Endl. [Pinus austriaca Höss.]

HABIT.—A large tree 60-80 feet high, with a trunk diameter of 2-4 feet; forming a massive, spreading crown of stiff, strong branches.

LEAVES.—In clusters of two; 3-6 inches long; slender, rigid, sharp-pointed, curved towards the twig; deep green on both faces. Persistent 3-6 years.

FLOWERS.—May-June; monoecious; the staminate cylindrical, subsessile, bright yellow, about 3/4 inch long; the pistillate cylindrical, small, bright red, subsessile.

FRUIT.—Autumn of first season, opening two years after full size is attained and remaining on the tree several years; erect, sessile, long-ovoid cones 2-3 inches long; scales smooth, lustrous, thickened at the apex and topped with a short spine in the center; seeds red-brown, 1/4 inch long, with wings 3/4 inch long.

WINTER-BUDS.—Oblong-conical, sharp-pointed, red-brown, resinous, about 1/2 inch long.

BARK.—Twigs brownish to olive-brown and smooth, becoming darker with age; thick, gray to nearly black on old trunks and coarsely and deeply fissured.

WOOD.—Light, strong, very resinous, red-brown, with thick, yellowish to reddish white sapwood.

NOTES.—Perfectly hardy. Adapts itself to a variety of soils. Well adapted for screens and wind-breaks. Easily transplanted when small. Grows rapidly.

PINACEAE

Scotch Pine. Scotch Fir

Pinus sylvestris L.

HABIT.—A large tree 60-80 feet high, with a trunk diameter of 1-2 feet; the side branches persist, forming a massive, wide-spreading crown.

LEAVES.—In clusters of two; 1-1/2-3 inches long; stiff, more or less twisted, spreading slightly from a short sheath; bluish- or often glaucous-green. Persistent 3-4 years.

FLOWERS.—May-June; monoecious; the staminate ovoid, short-stalked, yellowish, about 1/4 inch long; the pistillate oblong, reddish, short-stalked, about 1/4 inch long.

FRUIT.—Autumn of second season, falling as soon as ripe; pendent, stout-stalked, ovoid-conical cones 1-1/2-2-1/2 inches long; scales dull gray-brown, thickened at the apex into 4-sided, recurved points; seeds red-brown, nearly 1/4 inch long, with wings about 3/4 inch long.

WINTER-BUDS.—Oblong-ovoid, sharp-pointed, red-brown, resinous, about 1/4 inch long.

BARK.—Twigs reddish to orange-brown, becoming grayish; thick, dark orange-brown on old trunks and coarsely and deeply fissured.

WOOD.—Light, stiff, straight-grained, strong, heavy, hard, resinous, red-brown, with thick, yellow to reddish white sapwood.

NOTES.—Very rapid of growth. Reaches perfection only in cold or elevated regions. Adapts itself to a variety of soils. A valuable ornamental tree. Very useful for screens or shelter belts.

PINACEAE

Red Pine. Norway Pine

Pinus resinosa Ait.

HABIT.—A large tree 70-80 feet high, with a trunk diameter of 2-3 feet; stout, horizontal branches, form a broad, rounded, rather open crown.

LEAVES.—In clusters of two; 4-6 inches long; slender, straight, needle-shaped, sharp-pointed, flexible, from elongated, persistent sheaths; lustrous dark green. Persistent 4-5 years.

FLOWERS.—April-May; monoecious; the staminate in oblong, dense clusters, 1/2-3/4 inch long, composed of many sessile, purple anthers imbricated upon a central axis; the pistillate single or few-clustered at the end of the branchlets, subglobose; scales ovate, scarlet, borne on stout peduncles covered with pale brown bracts.

FRUIT.—Autumn of second season, falling the next summer; ovoid-conical, nearly sessile cones, about 2 inches long; scales thickened at the apex; seeds oval, compressed, light mottled-brown, with wings 1/2-3/4 inch long.

WINTER-BUDS.—About 3/4 inch long, ovoid or conical, acute, red-brown, with rather loose scales.

BARK.—Twigs orange-brown, becoming rough with the persistent bases of leaf-buds; thick and red-brown on the trunk, shallowly fissured into broad, flat ridges.

WOOD.—Light, hard, very close-grained, pale red, with thin, yellow to white sapwood.

DISTRIBUTION.—Very abundant in Clare County and northward; frequent on the east side of the state as far south as Port Huron.

HABITAT.—Sandy plains and dry woods.

NOTES.—Rapid of growth on the better soils. Difficult to transplant.

PINACEAE

Tamarack

Larix laricina (DuRoi) Koch [Larix americana Michx.]

HABIT.—A tree sometimes 80-100 feet high, with a trunk diameter of 1-2 feet; forming a broad, open, irregular crown of horizontal branches.

LEAVES.—Scattered singly along the leading shoots or clustered on the short lateral branchlets; linear, with blunt apex; rounded above, keeled beneath; about 1 inch long; bright green; sessile. Deciduous in early autumn.

FLOWERS.—April-May, with the leaves, monoecious; the staminate sessile, subglobose, yellow, composed of many short-stalked anthers spirally arranged about a central axis; the pistillate oblong, short-stalked, composed of orbicular, green scales (subtended by red bracts) spirally arranged about a central axis.

FRUIT.—Autumn of first season, but persistent on the tree for a year longer; ovoid, obtuse, light brown, short-stalked cones, 1/2-3/4 inch long; seeds 1/8 inch long, with pale brown wings widest near the middle.

WINTER-BUDS.—Small, globose, lustrous, dark red.

BARK.—Twigs at first grayish, glaucous, later light orange-brown, and finally dark brown; red-brown and scaly on the trunk.

WOOD.—Heavy, hard, very strong, coarse-grained, very durable, light brown, with thin, nearly white sapwood.

DISTRIBUTION.—Common throughout the state.

HABITAT.—Prefers cold, deep swamps, or in the north coming out on the drier uplands.

NOTES.—Becomes a picturesque tree in old age. Should be transplanted while dormant.

SUMMER KEY TO THE SPECIES OF PICEA

WINTER KEY TO THE SPECIES OF PICEA