Eastern cottonwood
Description
Leaves
Form
- Triangular, tip taper-pointed
- Often pendulous
- Usually 3–5 warty glands at the base of the leaf blade
- Neoformed leaves broadly ovate, hairy when unfolding
Length
- 5–10 cm
Colour
- Upper surface bright shiny green
- Lower surface slightly paler
Margin
- 20–25 rounded teeth per side, no teeth on the tip or near the petiole
- Narrow, translucent
- Teeth smaller and more numerous on neoformed leaves
Petiole
- Smooth
- Hairless
- Flattened
- Long
- Yellowish-green
Buds
Form
- Terminal bud 3-sided
- Slender, long-pointed
- Very resinous, hairless
- Lateral leaf buds slightly smaller, diverging from the twig
- Flower buds stout
- Leaf scars large, 3-lobed, with eyelash-like hairs at juncture of bud and scar
Length
- About 20 mm
Colour
- Yellowish-brown
Twigs
Form
- Stout, smooth, hairless
- Angular in cross-section
- Narrow ridges extend down from either side of the bud
- Lenticels sparse, linear
Colour
- Yellowish-brown
Flowers
Length
- Catkins 5–7 cm
Structure
- Dioecious
Fruits
Form
- Stalk hairless
- Capsules oval, tapering to both ends
- Splitting into 3 or 4 parts when mature
Length
- Mature seed catkins 15–25 cm
- Capsules 8–12 mm
Bark
Form
- Smooth, with age becoming deeply furrowed
Colour
- Yellowish-grey, with age becoming dark grey
Size
Height
- To 30 m
Diameter
- To 100 cm
Maximum age
- 50 years
Tree form
Forest-grown
Trunk
- Long, straight
Crown
- Small, rounded
Open-grown
Trunk
- Short, massive
- Often divided near the ground into a few large, wide-spreading limbs
Crown
- Broad, irregular-shaped, open
Root system
- Usually shallow, wide-spreading
- Sometimes deep
Habitat
Site
- Rich moist sites, stream banks
Associated species
- Mixed with other species
Range
In the Montreal area in Quebec, and near Lakes Erie and Ontario in southern Ontario; not a common tree
In Ontario, eastern cottonwood intergrades with plains cottonwood
Insects and mites
Insects that cause damage to this tree.
-
Carpenterworm
Scientific name: Prionoxystus robiniae (Peck)
-
Cottonwood crown borer
Scientific name: Sesia tibialis (Harris)
-
Poplar-and-willow borer
Scientific name: Cryptorhynchus lapathi (Linnaeus).
Foliage or buds
-
Aspen twoleaf tier
Scientific name: Enargia decolor (Walker)
- Eupithecia subfuscata (Haworth)
-
Lombardy leafminer
Scientific name: Paraphytomyza populicola (Walker)
-
Poplar bud gall mite
Scientific name: Aceria parapopuli (Keif.)
-
Poplar-and-willow borer
Scientific name: Cryptorhynchus lapathi (Linnaeus).
-
Satin moth
Scientific name: Leucoma salicis (L.)
Roots, bark, stem or trunk, or branches
Diseases caused by pathogens
Diseases caused by pathogens that cause damage to this tree.
Septoria (leaf-spot and) canker of poplars
Pathogen name: Sphaerulina musiva (Peck) Quaedvl., Verkley & Crous
-
Septoria (leaf-spot and) canker of poplars
Pathogen name: Sphaerulina musiva (Peck) Quaedvl., Verkley & Crous
Foliage or buds
Septoria (leaf-spot and) canker of poplars
Pathogen name: Sphaerulina musiva (Peck) Quaedvl., Verkley & Crous
-
Ink spot of aspen
Pathogen name: Ciborinia whetzelii (Seaver) Seaver
-
Leaf blight (Ventura populina)
Pathogen name: Venturia populina (Vuill.) Fabric.
-
Septoria (leaf-spot and) canker of poplars
Pathogen name: Sphaerulina musiva (Peck) Quaedvl., Verkley & Crous
Roots, bark, stem or trunk, or branches
Distribution map




