Michigan Trees Part 7

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.

[Ill.u.s.tration: +Jack Pine. Scrub Pine+

1. Cl.u.s.ter of leaves, 1.

2. Cross-section of leaf, enlarged.

3. Branchlet with unopened cone, 1.

4. Branchlet with opened cone, 1.

5. Cone-scale with seeds, 1.]

+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 cl.u.s.ters 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 cl.u.s.ters 1/2 inch long, composed of many sessile, yellow anthers imbricated upon a central axis; the pistillate in subglobose cl.u.s.ters, 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 sh.o.r.e 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.

[Ill.u.s.tration: +Austrian Pine. Black Pine+

1. Cl.u.s.ter of leaves, 1.

2. Cross-section of leaf, enlarged.

3. Unopened cone, 1.

4. Partly opened cone, 1/2.

5. Cone-scale with seeds, 1.]

+PINACEAE+

+Austrian Pine. Black Pine+

_Pinus laricio austriaca Endl._ [_Pinus austriaca Hoss._]

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

LEAVES.--In cl.u.s.ters 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, l.u.s.trous, 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 coa.r.s.ely 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.

[Ill.u.s.tration: +Scotch Pine. Scotch Fir+

1. Cl.u.s.ter of leaves, 1.

2. Cross-section of leaf, enlarged.

3. Unopened cone, 1.

4. Partly opened cone, 1.

5. Cone-scale with seeds, 1.]

+PINACEAE+

+Scotch Pine. Scotch Fir+

_Pinus sylvestris L._