Description
Tsuga – Hemlock –
There are 8 to 11 elegant evergreen monoecious, coniferous conical to pyramidal medium to large trees in the Pinaceae family, in this genus. They naturally occur in forest, 4 to 6 in Eastern Asia and 4 from North America. They produce flattened, usually linear leaves, with elevated mid vein beneath, are radially arranged or 2 ranked, and vary in length along the shoots. The small egg-oblong to almost spherical, terminal, pale to mid brown female cones become pendent as they mature, similar to those of Picea and drop off in the 2nd year, the male cones have few scales, and are almost spherical, up to 1/4″ across, and borne at the tips of lateral shoots. The bark is scaly and deeply furrowed with color ranging from gray to brown. Excellent specimen trees and very shade tolerant, especially when young, many are suitable for hedging. Dwarf cultivars are all good for bonsai work and shady rock gardens..
Grow in humus rich, moist but well drained, acidic to slightly alkaline soil in full sun or partial shade. They dislike urban environments or very exposed positions. Trim hedges from early to late summer.
Prone to gray mold (Botrytis), butt rot, rust, needle blights, snow blight, weevils, mites, aphids, and woolly adelgid.
T. mertensiana – Mountain Hemlock – This single trunk, slow growing, columnar-conical tree found from Alaska to California seldom exceeds 50′ feet tall and 20′ feet wide. It has thin square cracked or furrowed, gray bark. It produces thick, blunt tipped, linear, smooth edged, glaucous blue or gray-green leaves, up to 1″ long, are convex on both sides, and radially arranged. Female cones are oblong-cylindrical, up to 3″ long, and have reflexed scales when fully open. Susceptible to pollution and dry conditions.
‘Glauca’- is slow growing reaching 10′ feet tall and 6′ feet wide with glaucous, silver gray foliage.
Zones 6-8
