Betula
( bet - YOO - luh )
At-A-Glance InformationCommonly known as Birch, this genus of deciduous hardwood trees needs full sun and regular water. They will attract birds and butterflies to your garden and are known for their colored, papery peeling bark and drooping branches. Birch trees produce panicles and fruit that carry their interest through the dormant, bare season. Grow these trees in groves, in groups, or as trees lining driveways or property boundaries. Birch trees are also seen in landscapes planted in groves of just a few trees, for example three or five.
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Betula Species and Varietals
The genus Betula is a member of the plant family Betulaceae and includes between 30 and 60 species, depending on which authority is cited. The best growing zones for Birch trees vary depending on the species. For more information, see the descriptions below. To find your zone, click here: Zone Map.
Betula alleghaniensis (Betula lutea) (Yellow Birch, Golden Birch, Swamp Birch) This northeastern American native medium-sized tree that typically reaches between 60 and 80 feet tall at maturity (though they can reach upwards of 100 feet tall). These are long-lived trees, reaching between 150 and 300 years of age before declining. Very similar characteristics to Betula lenta. |
Betula ermanii (Erman's Birch) This species is highly variable, and is native to China, Japan, Korea, and the Russian Far East. These trees can reach up to 65 feet tall, but again are variable in form. These trees are widely cultivated outside of their native range as landscape ornamentals. Variety 'Grayswood Hill' (pictured) is a fantastic cultivar. |
Betula glandulosa (American Dwarf Birch, Resin Birch, Shrub Birch) Native to North America, this species of Birch forms a multi-stemmed shrub that reaches between 3.5 and 10 feet tall. Bark is smooth and dark brown. These trees are valued for their usefulness on sloped areas as erosion control plants, and also do very well stabilizing stream banks. |
Betula kenaica (Kenai Birch) These trees can reach up to 39 feet tall when mature, and have reddish-brown bark that may over time become pink or greyish-white. Flowers bloom in late springtime, and the fruits that follow drop off the tree in fall. This species is native to Alaska and other areas of northern North America. These plants have been used to flavor stews thicken soups, make beer, and eaten cooked. |
Betula lenta (Sweet Birch, Black Birch, Cherry Birch, Mahogany Birch, Spice Birch) This species is native to eastern North America and forms a medium-sized deciduous tree that reaches up to 115 feet tall in ideal conditions, heights between 50 and 80 feet are more typically seen, especially in cultivated landscapes. These trees are sometimes misidentified as Cherry trees, hence the common name 'Cherry Birch'. Bark is smooth when young (up 40-50 years old), and then develops splits. Bark doesn't begin to peel until these trees reach between 130-150 years old. |
Betula medwediewii (Transcaucasian Birch, Caucasian Birch, Medwediew's Birch) This species, native to Turkey, Georgia and Iran, forms a large, spreading shrub or multitrunked small tree that reaches about 15 feet tall in cultivation. Leaves turn yellow before dropping from the plant in fall. Cultivar 'Gold Bark' is a popularly grown ornamental. |
Betula neoalaskana (Alaska Birch, Alaska Paper Birch, Resin Birch) This species does well in cooler climates and is native to Alaska and northern areas in Canada. These trees typically reach between 50 and 65 feet tall, though they can reach up to 82 feet. Bark varies in color from pure white to reddish, pinkish, or light grey. |
Betula nigra (River Birch, Red Birch) This species is grown in zones 1-24 and is native to eastern North America, growing along the banks of streams and rivers. Grows quickly in its early years and reaches 50-90 feet tall and 40-60 feet wide. It can be trained into a singularly-trunked tree, but tends to fork towards the bottom if left uncorrected. Brown to black bark is flaky and curls. Leaves are diamond-shaped are glossy and green above, silvery underneath. Varieties include 'Dura-Heat' (heat-tolerant and borer-resistant), 'Heritage' (with lighter bark than the species, borer-resistant), 'Summer Cascade' (weeping birch, resists borer; reaches 15 feet tall and 20 feet wide). |
Betula papyrifera (Paper Birch, American White Birch, Canoe Birch) This short-lived Birch species is native to northern areas of North America. Individual trees reach 66 feet tall (in some circumstances up to 130 feet). In its natural habitat, these trees tend to form one trunk, but in landscapes this species is commonly seen as a multitrunked specimen. In warmer climates, these trees live around 30 years, but in more northern areas with cooler weather, they can live to be 100. |
Betula pendula (European White Birch, Silver Birch, Warty Birch, East Asian White Birch, Weeping Birch)
This species of Birch grows well in zones A2, A3, 1-12 and 14-24. They are native from Europe through Asia Minor and have a delicate appearance. Reaches 30-40 feet tall and half as wide. Bark is white with black clefts when mature, golden when new. Oldest bark is black (especially towards the bottom of the trunk). Leaves are glossy and rich green and the tree has an overall weeping habit. Very sensitive to borers. Choice varieties are outlined below.
This species of Birch grows well in zones A2, A3, 1-12 and 14-24. They are native from Europe through Asia Minor and have a delicate appearance. Reaches 30-40 feet tall and half as wide. Bark is white with black clefts when mature, golden when new. Oldest bark is black (especially towards the bottom of the trunk). Leaves are glossy and rich green and the tree has an overall weeping habit. Very sensitive to borers. Choice varieties are outlined below.
'Crimson Frost'
This variety has burgundy leaves throughout its leafing season. Somewhat resistant to borers. |
'Laciniata' ('Dalecarlica')
(Cutleaf Weeping Birch) Graceful habit with weeping branches. Will sunburn in hot, dry climates. |
'Purple Rain'
Leaves are purple-burgundy and hold color all summer long. |
'Trost's Dwarf'
This reaches 3 feet tall and wide. It is great for a bonsai subject, in a container, or as an addition to rock gardens. |
'Youngii'
(Young's Weeping Birch) Dome-shaped tree with branches that hang straight down. Stake to desired height and then branches will hang down from that point. Reaches 15 feet tall and 20 feet wide. Will sunburn in hot climates. |
Betula platyphylla japonica (Betula mandshurica japonica) (Japanese White Birch) This species is native to Japan and grows well in zones 1-11 and 14-24. It quickly reaches 40-50 feet tall and spreads about half as wide. Bark is white and leaves are glossy green. Variety 'Dakota Pinnacle' is a narrower selection that has a very upright habit. |
Betula utilis (Betula jacquemontii) (Himalayan Birch, Bhojpatra) This species is best in zones 3-11 and 14-17 and is native to northern India. It is a narrow tree with strikingly white bark and reaches 40 feet tall and 30 feet wide; eventually reaching 60 feet tall at full maturity. Somewhat resistant to borers. The bark of these trees was used in ancient times as a medium to record Sanskrit texts and scriptures. |
Caring for and pruning Birch Trees
Plant your birch tree in a spot that receives full sun. These trees can tolerate partial shade if necessary, but full sun is best. Ensure that soil is well-draining before planting. These trees prefer soils with a pH of between 5.0 and 6.5 (acidic to neutral). Mulch around the base of the tree after planting to help regulate soil temperature, suppress weed growth, and retain moisture. Keep mulch a few inches away from the trunk (and never let it touch the trunk). Young or newly installed trees should be watered regularly so that the soil is kept relatively moist (but not waterlogged). Mature trees are relatively water-wise, needing deep waterings during dry spells (especially in the summer and early fall). Although these trees don't necessarily need additional fertilizers if local soils are rich, if they seem to be struggling or if soil conditions are especially poor, they may benefit from an application of a slow-release balanced fertilizer in early springtime. Avoid over-fertilizing Birch trees, as it can harm them.
Prune your Birch tree as needed; the best time for pruning is in late winter or early springtime, before new growth is pushed out for the year. At this time, remove dead or damaged branches and thin out crowded branches if air circulation needs to be improved. Avoid heavy pruning. These trees have an upright growth habit for the most part, and will not need much in the way of pruning.
Harvesting Birch Oil or Extract
Birch oil is a product made from the bark of Birch trees, specifically those in the species Betula allaghaniensis (Yellow Birch) and Betula lenta (Sweet Birch). The oil is sometimes called Wintergreen Oil, though the true Wintergreen Oil is extracted from the plant Gaultheria procumbens. In springtime, carefully remove small sections of bark from a mature tree. Avoid taking too much bark from any single tree to prevent damaging it. The inner bark (the cambium layer) is where most of the oil is concentrated. Ends of branches also contain the oil in notable quantities, and can be cut into 1/4-inch pieces. Place the harvested bark and branch pieces in the pot of a distillation apparatus and add water to cover the pieces completely. Bring the pot to a boil, and let the heat naturally separate the oil from the water. Collect and decant the soil. Once separated, store in a dark glass bottle to protect the oil from light and degradation. Store in a cool, dark place.
Take care when manufacturing and storing Wintergreen Oil, as it contains methyl salicylate, which can be quite toxic. Fatal dosage is 7 grams for an adult, and 4.7 grams for a child. Keep the oil out of reach of children, and make sure that dosages are measured and taken correctly.
Prune your Birch tree as needed; the best time for pruning is in late winter or early springtime, before new growth is pushed out for the year. At this time, remove dead or damaged branches and thin out crowded branches if air circulation needs to be improved. Avoid heavy pruning. These trees have an upright growth habit for the most part, and will not need much in the way of pruning.
Harvesting Birch Oil or Extract
Birch oil is a product made from the bark of Birch trees, specifically those in the species Betula allaghaniensis (Yellow Birch) and Betula lenta (Sweet Birch). The oil is sometimes called Wintergreen Oil, though the true Wintergreen Oil is extracted from the plant Gaultheria procumbens. In springtime, carefully remove small sections of bark from a mature tree. Avoid taking too much bark from any single tree to prevent damaging it. The inner bark (the cambium layer) is where most of the oil is concentrated. Ends of branches also contain the oil in notable quantities, and can be cut into 1/4-inch pieces. Place the harvested bark and branch pieces in the pot of a distillation apparatus and add water to cover the pieces completely. Bring the pot to a boil, and let the heat naturally separate the oil from the water. Collect and decant the soil. Once separated, store in a dark glass bottle to protect the oil from light and degradation. Store in a cool, dark place.
Take care when manufacturing and storing Wintergreen Oil, as it contains methyl salicylate, which can be quite toxic. Fatal dosage is 7 grams for an adult, and 4.7 grams for a child. Keep the oil out of reach of children, and make sure that dosages are measured and taken correctly.
Propagation
Birch trees can be propagated either by using cuttings or from seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. Propagating any species of Birch tree is difficult via cutting; seed propagation has a much higher success rate. To propagate your tree, follow the instructions below:
Propagating Birch by Cutting
Propagating Birch by Seed
Propagating Birch by Cutting
- Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. Regular potting soil is a good medium for Birch propagation via cutting.
- In late spring or early summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more 6-8 inch portion(s) of the end of a non-blooming branch and strip all leaves but the top pair. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
- Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about eight weeks have passed, your cutting should be rooted. When you notice new growth on your propagated Birch, you'll know you have roots under the soil surface.
- Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not soggy, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new Birch tree.
Propagating Birch by Seed
- Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. You will also need individual pots for each seedling that grows.
- Harvest your seeds. Birch tree seeds can be harvested when catkins dry and turn brown to dark brown. Seeds are small, and have wings that allow them to float through the air away from the parent tree. Remove catkins from the tree and place them in your paper bag.
- Birch tree seeds will need a cold-stratification period in order to germinate. Remove your seeds from the paper bag and place them on the soil surface of a tray filled with well-draining compost. Sprinkle more compost over the top of the seeds, so that they are just covered. Carefully spray down the soil surface, being sure to not dislodge the delicate seeds from their soil coverings. Place the tray in the refrigerator, and leave for six months.
- After the six months have passed, place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes a few weeks from the date of sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
- Keep the seedling's potting medium moist, but not wet. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.
Problems and Pests
Birch trees commonly suffer from the following pests and diseases:
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For more information on these pests and diseases, including how to deal with them when they pop up, visit the following links:
Gallery
Videos
How to identify a Paperbark Birch.
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How to grow and care for River Birch (Betula nigra).
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All about Himalayan Birch (Betula utilis jaquemontii).
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Investigate some of the impressive qualities of Birch bark.
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An in-depth video about Birch trees, their history and cultural significance.
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Everything you need to know about Birches.
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Resources
The New Sunset Western Garden Book: The Ultimate Gardening Guide (2012) - Page 195, Betula
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