Paperbark Maple (Acer griseum)

Paper Bark Maple, Paperbark Maple

The Acer Griseum tree, also known as the Paper-Bark maple tree, is a magnificent specimen that can be found throughout North America. This hardy tree is known for its striking paper-like bark, peeling away in thin layers to reveal a bronze-colored inner bark.

Prized for its showy fall color and interesting form, the Acer Griseum is a popular choice for both residential and commercial landscapes.

While the Acer Griseum is a tough tree that can withstand cold winters and hot summers, it does require some special care to ensure that it stays healthy and grows to its full potential. Here are a few tips on Acer Griseum care.

I. Appearance and Characteristics 

Acer griseum, the paperbark maple or blood-bark maple, is a species of flowering plant in the family Sapindaceae, native to central China. Acer griseum is found in the Chinese provinces of Gansu, Henan, Hubei, Hunan, Shaanxi, Shanxi and Sichuan, at altitudes of 1,500–2,000 m (4,921–6,562 ft).

It is a small to medium-sized deciduous tree, reaching 6–9 m (20–30 ft) tall and 5–6 m (16–20 ft) wide, with a trunk up to 70 cm (28 in) in circumference. The bark is smooth, shiny orange-red, peeling in thin, papery layers; it may become fissured in old trees. The shoots are densely downy at first, this wearing off by the second or third year and the bark exfoliating by the third or fourth year.

The leaves are compound, with a 2–4 cm petiole with three leaflets, each 3–10 cm long and 2–6 cm broad, dark green above, bright glaucous blue-green beneath, with several blunt teeth on the margins.

The yellow flowers are androdioecious, produced in small pendent corymbs in spring, the fruit being a paired samara with two winged seeds about 1 cm long with a 3 cm wing.

II. How to Grow and Care

Sunlight

The Acer Griseum thrives and grows well in full sun to partial shade. In hot summer climates, it’s best to provide some afternoon shade to protect the tree from the harsh afternoon sun. While the tree can tolerate some shade, it will not produce as many flowers, and its fall color will be less vibrant.

Additionally, when exposed to extreme heat or direct sunlight, the leaves of the Acer Griseum can scorch and turn brown. If this happens, simply remove the affected leaves and provide the tree with some relief from the heat.

Temperature and Humidity

Hardy in zones 4 through 8, paperbark maple trees can tolerate a wide range of temperatures. They’re also considered drought-tolerant but can experience leaf scorch in very dry, hot weather.

Watering

A paperbark maple’s water needs are considered medium or moderate. Make sure the roots stay moist during the first two or three growing seasons. After that, you can give the roots a deep soak every week, but only during hot, dry weather. Otherwise, mature trees usually don’t need additional watering beyond natural precipitation.

Soil

The best soil for paperbark maple trees is moist and well-drained, but the species can also tolerate many different soil types and textures, including clay soils that challenge many other trees. Paperbacks do well in a variety of soil pH levels, but neutral to slightly acidic soil is ideal.

Fertilizing

The best fertilizer to use on an Acer Griseum is an all-purpose, slow-release granular fertilizer. Apply the fertilizer in early spring, before new growth begins. Preferably, if you can provide organic fertilizer, it will be the best option for your tree.

Planting Instructions

When planting a Paperbark Maple, select a location with well-drained soil and adequate space for the tree to reach its mature size. It is best to plant in the spring or fall. Dig a hole twice as wide as the root ball and just as deep. Place the tree in the hole, backfill with soil, and water thoroughly. Mulching around the base of the tree can help retain moisture and regulate soil temperature.

Pruning

Soon after planting your paperbark maple tree, you will need to decide if you want the tree to have a single trunk or multiple stems. To train it as a single-trunk specimen, choose a central leader and prune away all others. Beyond this kind of shaping, not much pruning is required—just periodically remove any dead, diseased, or damaged wood as needed. Pruning is best done as soon as the tree enters dormancy in late fall or early winter. If you wait until spring to prune, don’t do it until later in the season, as maples tend to bleed sap.

Propagation

Growing from seed is the preferred method of starting a paperbark maple tree over propagation through grafting, which is notoriously difficult and unsuccessful. However, growing from seed can still take a lot of trial and error (not to mention numerous years), so selecting an already established young tree from a nursery is typically the route to go for most homeowners. If you’re still interested in growing a tree via seed, you can follow the below steps:

  • Start by soaking the seed in hot tap water and allowing it to sit for at least 24 hours to begin coaxing it out of dormancy.
  • Combine a 50/50 mixture of compost and perlite in a large plastic freezer bag. The mixture should be moist but not wet.
  • Place the soaked seed inside the bag and put it somewhere warm for at least 17 weeks.
  • After the 17-week warm period is up, the seed will need another 17 weeks in the cold to break dormancy. A fridge is a great option for this.
  • Once the cold pre-treatment has finished, your seed is ready to be planted. Fill a seed tray with quality compost and plant the seeds no more than 1 centimeter deep into the soil.
  • Keep the seedling at a moderate temperature (no warmer than 80 degrees Fahrenheit) as it germinates. It should grow between 4 and 15 inches the first year and will be ready to be planted in its permanent position after about two years.

Pests and Diseases

The Paperbark Maple is relatively free of serious pests and diseases. However, it can be susceptible to common maple pests such as aphids (Aphidoidea) and scale insects (Coccoidea), which can be controlled with horticultural oils or insecticidal soaps. Proper cultural practices, such as adequate watering and avoiding mechanical injury, can help prevent many problems.

III. Uses and Benefits 

Acer griseum was introduced to cultivation in Europe in 1901 by Ernest Henry Wilson for the Veitch Nurseries in the UK, and to North America shortly after. It is one of many species of maples widely grown as ornamental plants in temperate regions. It is admired for its decorative exfoliating bark, translucent pieces of which often stay attached to the branches until worn away. It also has spectacular autumn foliage which can include red, orange and pink tones. Cultivars include the columnar Copper Rocket.

This plant has gained the Royal Horticultural Society’s Award of Garden Merit.

In 2015, the North America-China Plant Exploration Consortium (NACPEC) conducted an expedition specifically targeting Acer griseum for seed collection with the object of increasing the genetic diversity of plants in cultivation. Propagation of Acer griseum is somewhat difficult as seeds have the same parthenocarpic tendencies as those of Acer maximowiczianum.

Paperbark Maple (Acer griseum) Details

Common name Paper Bark Maple, Paperbark Maple
Botanical name Acer griseum
Plant type Tree
Hardiness zone 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b
Growth rate Slow
Harvest time Fall
Height 20 ft. 0 in. - 30 ft. 0 in.
Width 20 ft. 0 in. - 30 ft. 0 in.
Sunlight Full sun (6 or more hours of direct sunlight a day)
Soil condition Clay
Flower color Gold/Yellow
Leaf color Gold/Yellow