Why do the leaves shake?

The leaf stems are flattened, which causes them to flutter easily in the wind.

Yes, they spread aggressively through underground root suckers to form large colonies.

Plant guide

Quaking Aspen.

Populus tremuloides

Pronounced POP-yoo-lus trem-yoo-LOY-deez

Also known as American Aspen, Giant Aspen, Pando, Quaking Aspen, Trembling Aspen, aspen poplar, mountain aspen, popple

The quaking aspen is a beautiful deciduous tree known for its leaves that flutter in the slightest breeze. It is a hardy native species that often grows in large clonal colonies. You will love the way its white bark brightens up a landscape.

At a glance

Care level: Easy
Plant type: Deciduous tree
Light: Full sun
Indoor light: Direct sun
Water: Every 7 to 14 days
Mature size: 20 to 80 feet
Growth rate: Fast
Hardiness: USDA 1 to 7
Bloom time: Early spring

Care

Plant this tree in a spot with plenty of room for its roots to spread. Keep an eye out for leaf spots or bark damage which can signal stress. It thrives best when it has consistent moisture during its first few years.

Watering: Keep the soil consistently moist but not waterlogged, especially while the tree is young.
Feeding: Apply a balanced fertilizer in early spring before new growth begins.
Pruning: Remove dead or damaged branches during the dormant winter season.
Repotting: This tree is best suited for the ground, but if kept in a container, move it to a larger pot every few years.
Soil: Well drained, moist, loamy soil
Soil pH: Acidic to neutral
Temperature: -45 to 35°C
Humidity: 30 to 70%
Drought tolerance: Moderate
Lifespan: Perennial, typically 50 to 150 years.
Deer and rabbits: Low

Signs it needs repotting

Roots growing out of drainage holes
Stunted growth despite proper care

Safety

People: The bark contains salicin, which is chemically related to aspirin and may cause reactions in those with salicylate sensitivities.
Children: The catkins and seeds can be a choking hazard if ingested by small children.
Contact allergens: The bark and buds may cause mild skin irritation in sensitive individuals.
Airborne allergens: The windborne pollen is a significant allergen for many people during the early spring.
Edibility: The inner bark is technically edible but requires extensive processing and is generally considered a survival food rather than a culinary ingredient.

How to identify it

Smooth white bark
Small heart shaped leaves
Flattened leaf stalks
Leaves tremble in wind
Golden yellow autumn color

Height: 6 to 25m
Spread: 3 to 9m
Leaves: green, yellow, deciduous
Flowers: green, gray, 2 to 8cm
Fruit: brown, Late spring

Common problems

Hypoxylon canker — A fungal infection that causes sunken, discolored lesions on the trunk.
Aphids — Small insects that suck sap and produce sticky honeydew on foliage.

Growing it

Propagation: cuttings, seed, suckers
When to plant: spring, autumn
Overwintering: No special winter care is needed as this tree is fully hardy in cold climates. Ensure the soil remains moist before the ground freezes.
In containers: Not recommended for containers due to their massive root systems and need for space.

Root Suckers

Locate a healthy sucker growing from the parent root system.
Sever the connection to the main root with a sharp spade.
Carefully lift the sucker with as much root mass as possible.
Replant immediately in a sunny location with moist soil.

Plant aspens in groups to mimic their natural habit of forming clonal colonies.

Grows well with

Douglas Fir — They often grow together in mixed forest stands in the wild.
Rocky Mountain Maple — It thrives in the same understory conditions as the aspen.

Similar species

Bigtooth Aspen — It shares a similar growth habit but has larger, coarser leaf teeth.

Science

Family: Salicaceae
Genus: Populus
Order: Malpighiales
Class: Magnoliopsida
Native range: Across North America from Alaska to Mexico.
Conservation: This species is widespread and not currently of conservation concern.

Aspens are pioneer species that quickly colonize areas after forest fires or other disturbances.

Value to wildlife: larval host plant, nesting site, food source for mammals
Pollinators: bees, butterflies
Uses: ornamental shade tree, land reclamation, wildlife habitat, woodworking

Through the year

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Flowering

Fruiting

Foliage

Ecological indicators

Salinity: 2/9
Soil reaction: 6/9
Light: 8/9
Temperature: 3/9
Moisture: 5/9
Nutrients: 4/9

Taxonomy resolved against GBIF.

Questions people ask

Why do the leaves shake?: The leaf stems are flattened, which causes them to flutter easily in the wind.
Do they spread?: Yes, they spread aggressively through underground root suckers to form large colonies.

Where the name comes from

The name tremuloides refers to the trembling motion of the leaves, while Populus is the classical Latin name for the poplar tree.

Good to know

The leaves tremble in the slightest breeze due to their flattened petioles.
Aspens are the most widely distributed tree species in North America.
The bark is photosynthetic, allowing the tree to produce energy even without leaves.
Aspen wood is lightweight and often used for matches and crates.

Is your quaking aspen looking unwell?

This page is a general guide. Pocket Botanist diagnoses problems from a photo of your actual plant, works out watering for your light and conditions, and reminds you when care is due.

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This guide was generated with AI and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.