Habitat

• native to eastern North America
• typically found on northern and eastern slopes with cooler, moister environmental conditions
• zone 3

Habit and Form

• a needle evergreen
• medium to large tree
• 40' to 70' tall, but can grow larger
• conical or pyramidal shape with a 25' to 30' spread
• soft, graceful, horizontal to pendulous branches
• fine texture

Summer Foliage

• leaves are spirally arranged, but are held in a 2-ranked fashion
• needles are flattened
• needles are 0.25" to 0.75" long and about 0.10" wide
• new foliage is dark green above with 2 whitish bands on the underside
• leaf margins minutely serrulate
• shoots pubescent

Autumn Foliage

• evergreen, no fall color

Flowers

• monoecious, with male and female flowers
• small and not ornamentally important

Fruit

• small cones, about 0.5" to 1.0" long
• turning light brown in the fall
• can be borne in large numbers

Bark

• overall brown color
• bark changes from smooth, to flaky and scaly, and finally to wide flat ridges with age

Culture

• best growth on cool, moist, well-drained soils
• transplant from containers or B&B
• avoid dry soils and hot locations
• dislikes very windy sites
• full sun or partial shade is best
• tolerant of relatively heavy shade
• can be pruned heavily in the spring for hedging

Landscape Use

• lawn tree
• specimen
• can be sheared to form an effective screen or hedge
• excellent evergreen for screening use in shaded locations where most needle evergreens fail
• in groves or small groupings
• dwarf forms as rock garden plants, accent plants or foundation plants

Liabilities

• not tolerant of pollution
• not tolerant of salt spray
• spider mites
• deer like to browse the foliage or rub off the bark with their antlers
• not tolerant of heat or drought
• hemlock wooly adelgid is a new and devastating insect pest that can be easily controlled, but left unchecked can kill large plants in 3 years

ID Features

• pyramidal, medium-sized, needle evergreen tree with horizontal to pendulous, graceful branches
• short flattened needles
• needles held in 2-ranked fashion
• T. caroliniana, with which T. canadensis is often confused, has more of its needles spirally distributed around its shoots
• shoots pubescent
• has minutely serrulate leaf margins, while T. caroliniana has smooth margins
• twigs roughened by persistent leaf bases remaining after needles fall
• numerous, small cones

Propagation

• by seed
• cultivars are grafted

Cultivars/Varieties

Dozens of hemlock cultivars are known in collection, but those presented below are commonly offered and offer a glimpse at the diversity available.

'Albospica' - This compact plant has bright white new growth and benefits from light shade. 'Gentsch White' is similar, forming a rounded compact plant to 4' tall and wide. The tips of the branches are silvery on this plant.

'Aurea Compacta' (also known as 'Everitt's Golden') - This smaller form grows stiffly upright, but it is chiefly notable for its bright gold foliage. 'Golden Splendor' is an upright-growing form with golden foliage that grows quickly in the landscape.

'Cole's Prostrate' - Originally found in New Hampshire, this is a true prostrate form that creeps along the ground and spreads widely. It appreciates light shade.

'Curly' - A very unusual form, this plant features congested branches bearing needles which curl around the stems.

'Horsford Contorted' (also known as 'Pig Tails') - Another addition to the limited list of small trees with contorted growth, this selection offers branches that are coiled and twisted. It forms a small tree at maturity and is a good conversation piece when well placed in the garden.

'Jeddeloh' - One of the more popular cultivars, this plant forms a small mound of layered branches. The plant tends to have a depression in its center, thus many observers refer to this selection as the "Bird's Nest Hemlock".

'Minuta' and 'Pygmaea' - These are micro-miniature rock garden curiosities discovered in Vermont. They form dwarf buns of dark green needles that only increase at the rate of .25"-.5" per year.

'Sargentii' (also known as f. pendula and 'Pendula') - The most common cultivar available and one of the most handsome, this selection is a large weeping tree that may reach 15' tall and twice as wide. The weeping branchlets are held aloft by thick stems, giving this sturdy weeper a graceful appearance. The needles are dark green and the plant usually forms cones.

'Watnong Star' - Discovered in New Hampshire, this rounded compact plant features foliage that is frosted with white, especially on new growth.