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hazel alder

Alnus serrulata · Betulaceae

hazel alder (Alnus serrulata)
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hazel alder (Alnus serrulata) is a perennial tree in the Betulaceae family. It is native to North America. USDA records it as hardy in zone 4 and warmer, down to about -23°F.

At a glance

Typetree Derived
Lifecycleperennial USDA
Native statusnative USDA
Mature height30 ft USDA
Lightfull-sun USDA
Water needhigh USDA
Growth raterapid USDA
Soil pH5–7 USDA
BloomMarch–May USDA
Hardiness zones4 and warmer USDA
Guild layerunderstory Derived
Nursery availabilityRoutinely Available USDA

USDA quoted from the USDA PLANTS database · Derived computed by a fixed rule from those columns. No value on this page is estimated.

Growing conditions

It needs full sun. USDA rates it as having needs consistently moist ground. Its drought tolerance is rated low. It tolerates saturated, poorly drained ground well (USDA rates its anaerobic tolerance high). It is recorded on soils from pH 5 to 7 — a broad range that spans acidic through mildly alkaline ground. Its cold limit is zone 4.

Size and growth

At maturity it reaches about 30 ft, making it a substantial woody plant. It grows quickly.

Bloom period

USDA records a bloom period of March through May.

A flowering date, not a pollinator rating.

Foliage, flower and season

Summer foliage is green, coarse in texture. Its flowers are not conspicuous — a plant for form and foliage. Its active growth period is spring and summer. USDA rates its lifespan as moderate.

What the site needs to provide

USDA records it across sites receiving 32 to 60 inches of annual precipitation. It needs at least 120 frost-free days to finish its season. It roots to at least 24 inches. Fertility requirement: medium.

Propagating it

Propagate it from seed, bare root and container stock. Seed needs cold stratification — a period of moist chilling — before it will germinate, so sow in autumn or chill it artificially before a spring sowing. Its seed spreads at a moderate rate. It spreads vegetatively at a slow rate.

Resilience and wildlife

Browsing animals find it moderately palatable, so expect deer and rabbits to take an interest. Its fire tolerance is rated high. Its growth form is recorded as multiple stem.

Role in a guild

Understory. In a layered planting this is the layer beneath the canopy, tall enough to hold structure but shaded from above. The layer is derived by a fixed rule from growth habit and mature height.

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Tags

deciduouswet-tolerantclay-tolerantsandy-soilnativenitrogen-fixerfull-sunfast-growing

Related plants

Others in Alnus

Similar role and hardiness

Where this data comes from

Every value on this page comes from the USDA PLANTS database record for symbol ALSE2, or is computed from those values by a fixed rule. Nothing here is estimated or model-generated. Where USDA publishes no value, this page omits the claim rather than filling the gap.

Read our full data sources and methodology.

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