SelecTree: Tree Detail
Alnus incana subsp. tenuifolia
Photo Locations: Morton Arboretum - Lisle, IL, UC Berkeley Botanic Garden - Berkeley, CA, Los Angeles County Arboretum - Arcadia, CA and Regional Parks Botanic Garden, Tilden Regional Park - Berkeley, CA
Utility friendly tree.
Extremely hardy to cold. The name 'incana' refers to the white underside of the leaves. Often found near water.
Native to California.
Additional Common Names
MOUNTAIN ALDER, THIN-LEAF ALDER
Erect or Spreading with a Low Canopy.
Has Deciduous foliage.
Height: 20 - 25 feet.
Width: 15 - 20 feet.
Growth Rate: 24 to 36 Inches per Year.
Longevity 40 to 150 years.
Leaves Ovate, Medium to Dark Green, Bronze or No Change, Deciduous.
Flowers Inconspicuous. Green, Red or Yellow. Flowers in Spring. Has separate male and female flowers on the same tree (monoecious).
Prolific, Brown Cone, Medium (0.50 - 1.50 inches), fruiting in Fall, Winter or Summer.
Bark Dark Gray or Red Brown, Smooth.
Shading Capacity Rated as Dense in Leaf.
Shading Capacity Rated as Moderately Dense out of Leaf.
Litter Issue is Dry Fruit.
Tree Site Conditions & Constraints
Sunset Zones 2, 3, 7 and 10.
USDA Hardiness Zones 5 - 8.
Exposure Full Sun to Partial Shade.
Wet to Moist Soil.
Loam or Sand Texture.
Highly Acidic to Neutral Soil pH.
Seaside Tolerance is Not Suited.
Pests & Disease Information
Susceptible to Armillaria and Root Rot.
Health, Safety & Environmental Concerns
Root Damage Potential Rated as Moderate.
Allergy Health Hazard.
Desirable Wildlife Plant.
Special Uses & Values
Riparian or Screen.
Cite this tree:
SelecTree. "Alnus incana subsp. tenuifolia Tree Record." 1995-2018. Jun 21, 2018.
< https://selectree.calpoly.edu/tree-detail/alnus-incana-tenuifolia >