Betula utilis jacquemontii, otherwise known as the Himalayan Birch, is the whitest of white stemmed silver birches. A fast-growing deciduous tree, it has sensationally white bark and large oval mid-green leaves. It provides a degree of autumn colour when the leaves turn yellow, and lovely long light brown catkins in early spring.
I. Appearance and Characteristics
Betula utilis, the Himalayan birch (bhojpatra, Sanskrit: भूर्ज bhūrjá), is a deciduous tree native to the Western Himalayas, growing at elevations up to 4,500 m (14,800 ft). The Latin specific epithet utilis means “useful”, and refers to the many uses of the different parts of the tree. The white, paper-like bark was used in ancient times for writing Sanskrit scriptures and texts. It is still used as paper for the writing of sacred mantras, with the bark placed in an amulet and worn for protection. Selected varieties are used for landscaping throughout the world, even while some areas of its native habitat are being lost due to overuse of the tree for firewood.
Betula utilis was described and named by botanist David Don in his Prodromus Florae Nepalensis (1825), from specimens collected by Nathaniel Wallich in Nepal in 1820. Betula jacquemontii (Spach), first described and named in 1841, was later found to be a variety of B. utilis, and is now Betula utilis var. jacquemontii.
In its native habitat, B. utilis tends to form forests, growing as a shrub or tree reaching up to 20 m (66 ft) tall. It frequently grows among scattered conifers, with an undergrowth of shrubs that typically includes evergreen Rhododendron. The tree depends on moisture from snowmelt, rather than from the monsoon rains. They often have very bent growth due to the pressure of the deep winter snow in the Himalaya.
Leaves are ovate, 5 to 10 cm (2.0 to 3.9 in) long, with serrated margins, and slightly hairy. Flowering occurs from May–July, with only a few male catkins, and short, single (sometimes paired) female catkins. The perianth has four parts in male flowers, and is absent in the female flowers. Fruits ripen in September–October.
The thin, papery bark is very shiny, reddish brown, reddish white, or white, with horizontal lenticels. The bark peels off in broad, horizontal belts, making it very usable for creating even large pages for texts. A fungal growth, locally called bhurja-granthi, forms black lumps on the tree weighing up to 1 kg.
The wood is very hard and heavy, and quite brittle. The heartwood is pink or light reddish brown.
II. How to Grow and Care
Sunlight
Himalayan birch prefers full sun, but it will grow in part shade where it can receive direct sunlight for two to six hours of the day. Afternoon shade can be beneficial in shading the shallow roots, especially in the hotter areas of Zone 7.
Temperature and Humidity
Native to the Western Himalayan Mountains of Kashmir and Nepal, it does best in temperate summers and cold winters. Birch trees prefer cooler summer weather; the 65-to-80-degree Fahrenheit range is ideal for them. Extremely hot weather, above 90 degrees Fahrenheit, can damage the tree and stunt its growth. These trees thrive in average humidity.
Watering
Himalayan birch can tolerate very wet soil. It is often used in wetland restoration. In well-draining soils, it can grow up to 18 inches per year. Use a soaker hose to establish strong roots during its first year.
Soil
It will thrive in just about any soil type, from clay to loam to sand. Like other birches, its roots are shallow. Plant in a low-traffic spot.
After planting, cover the planting area with mulch to help keep the roots cool and moist. Consider companion plants such as evergreen groundcovers, which will protect and shade the roots further.
Fertilizing
Birch trees are hardy enough to withstand a variety of poor soils but can grow stronger with a low-nitrogen fertilizer. Choose a slow-release formula with added iron.
Pruning
A deep-rooted Himalayan birch needs very little care. Prune in late autumn or winter, never spring because of running sap.
Propagation
You can propagate Himalayan birch from a cutting taken in the late spring or early summer.
- Choose a stem that is still green and pliable but beginning to turn brown.
- Dip the cut stem into a rooting hormone. Plant it in a 5-inch pot filled with a well-draining potting mix.
- Keep it evenly moist. It might take several months for the new stem to grow new leaves and for roots to develop. Plan on keeping the new plant in a sheltered location or indoors for the first season until it has grown into a strong sapling.
- Acclimate it slowly to the outdoors for two or three months, then plant the sapling in the ground in cool weather in the fall.
How to Grow from Seed
Alternatively, you can also grow the tree from seed, which requires cold stratification:
- In the summer, choose soft and green cone-like fruit that contains the seeds from the tree. Let them dry out for two weeks or so in a paper bag. Shake the bag vigorously to loosen the winged seeds.
- Sow the seeds in 5-inch pots in a mixture of peat, potting soil, and coarse sand, pressing them just below the surface. Water the seeds thoroughly.
- Cover each pot with a plastic bag and place the pot in the refrigerator for two months. Check periodically to make sure the potting mixture stays moist.
- Move the plants to a sunny, warm location of about 75 to 85 degrees Fahrenheit. The seeds will germinate in four to six weeks.
- When the saplings are only about 1 inch tall, move them outdoors to light shade. Keep them sheltered from strong rains or winds. Slowly acclimate them to direct sun over two or three months. Plant them in the ground in autumn.
Potting and Repotting
Himalayan birch is a large tree with an extensive root system. Growing them in containers is not recommended.
Overwintering
Himalayan birch is a hardy tree that and an established tree will handle winter just fine. Smaller trees can benefit from several inches of mulch to help protect the roots during the first several years of growth.
Pests and Diseases
Hot or humid conditions can often affect birch. A weakened birch is vulnerable to the bronze birch borer, a wood-boring beetle that girdles the trunk.1 Japanese beetles can also damage foliage.
Aphids, birch leaf miners, and birch skeletonizers pose minor and less frequent problems. (If the ground is sticky beneath the tree, this could be excrement from aphid feeding.) Generally, when a birch tree is stressed by insects, it is more susceptible to cankers.
III. Uses and Benefits
The bark of Himalayan birch was used centuries ago in India as paper for writing lengthy scriptures and texts in Sanskrit and other scripts, particularly in historical Kashmir.
The bark is still used for writing sacred mantras, which are placed in an amulet and worn around the neck for protection or blessing. This practice was mentioned as early as the 8th or 9th century CE, in the Lakshmi Tantra, a Pancaratra text. According to legend, the bark was also used as clothing by attendants of Shiva.
The bark is widely used for packaging material (particularly butter), roof construction, umbrella covers, bandages, and more. The wood is used for bridge construction, and the foliage for fodder. The most widespread use is for firewood, which has caused large areas of habitat to be eliminated or reduced. Parts of the plant, including the fungal growth (bhurja-granthi) have also long been used in local traditional medicine.
IV. Birch Tree Varieties
As an alternative that is less prone to disease than Himalayan birch, you might consider planting a birch tree variety that is native to North America such as:
- Bog birch (Betula pumila), a medium-size, shrub-like birch for wet locations
- River birch (Betula nigra), a fast-growing tree valued for its exfoliating reddish-brown bark and buttery yellow fall color
- Cherry birch (Betula lenta), a large landscape tree with bark that resembles cherry trees
