| General Description | In it’s native habitat Tsuga diversifolia is a tall pyramidal tree with a broad, dense, crown. It has a long-curved trunk that often forks midway up the tree. Often a more shrub-like form in cultivation. |
| ID Characteristic | Needles are oblong, small, glossy green in colour, and have notched tips with two white strips that run on the underside. Young branches begin reddish brown and become grey with age. Bark is rough with vertically grooved grey scales. |
| Shape | Tall, forked, and narrow. The crown is conical when young, but gradually becomes more broad and rounded with age. In cultivation Tsuga diversifolia has a tall, narrow, shrub like form. |
| Landscape | Not commonly used in the landscape as it must compete with the many cultivars of Tsuga canadensis. When it is in use it is an excellent evergreen for dense shaded areas of the landscape, as well as rock gardens due to its slow growing shrub form. In Japan it is often used in both parks and Japanese style gardens, as well as an excellent bonsai tree. |
| Propagation | When propagating Tsuga diversifolia it is recommended to propagate via cuttings rather than seed. It is difficult to separate the poor quality seed, as one pound of seed can contain around 187,000 individual seeds. Seeds require cold stratification, at a temperature of 1° to 5° C for 1 to 4 months. Seeds in a laboratory condition will require cold stratification for 21 to 28 days. As the preferred method, cuttings should be harvested from January to around mid February and should be placed in a moist environment. Cuttings should be dipped in 2% IBA rooting hormone, and placed in a peat:perlite (1:1) mixture for a minimum of 4 months, in a chamber with bottom heat and regular misting. |
| Cultivation | Tsuga diversifolia requires moist, well drained soil, in partial shade to full shade. It can tolerate full sun but prefers cool moist conditions. It is a fairly thirsty tree when young and is incredibly intolerant to drought and dry spells. Similar to other hemlocks it has very poor salt tolerance, so it is unsuitable for most urban environments. |
| Pests | Shares common pests with others of the Tsuga genus, including Hemlock looper, and Spruce spider mite, as well as common cankers, needle blights, rusts, and rots. This species is resistant to Adelges tsugae also known as the Hemlock woolly adelgid. |
| Notable Specimens | Tsuga diversifolia can be found on the campus of the University of Maine, as well as in Mount Congreve Gardens in Ireland. Although to see the species in its full glory, it is recommended to go to its native habitat of Japan in the mountains of Honshu, Kyushu, and Shikoku |
| Habitat | Found in the mountainous regions of Japan in montane and subalpine mixed forests between 700 and 2000 m above sea level. It thrives in cool woodland conditions with heavy snowfall in the winter, and abundant rainfall in the spring and summer. |
| Bark/Stem Description | Orange-brown bark patterned in large scales. Often furrowed and fissured on mature specimens. Shoots and stems begin distinctly pubescent, twisted, and orange-brown in colour; becoming smoother, more ridged and a dull brown as they mature. |
| Flower/Leaf Bud Description | Buds are obovoid, 2-3 mm in length, and dark brown in colour. Can often be slightly resinous, or not resinous at all. |
| Leaf Description | Needle like leaves are small, glossy green, and densely arranged in two ranks along the side of the stem. They are about 1 cm long and 2 mm wide with smooth edges and a notched tip. Two parallel white strips run along the underside of the foliage. |
| Flower Description | No significant flower. Pollen cones are 3-5 mm in length and are yellow in colour. |
| Fruit Description | The nearly sessile cones are obovoid and 1-2 cm in length. Found numerously on outer branches of the crown. They begin a purplish green colour, gradually ripening into a reddish or dark brown as they age. Seeds are ovoid, measuring 2-3 mm in length with large orange-brown wings that are 6-8 mm x 3-4 mm in size. |
| Colour Description | Foliage is a glossy green in colour, keeping the same hue year-round. Bark is orange-brown. Cones begin a purplish green, turning reddish or dark brown as they ripen. Pollen cones begin brown and turn yellow when shedding pollen. |
| Texture Description | Tsuga diversifolia is a dense and smooth textured plant consistently throughout the year. |