The Thinleaf alder (Alnus incana subsp. tenuifolia)is a tall fully hardy perennial deciduous tree/shrub with purple flowers in early Spring. It requires high levels of water. This plant requires a minimum of 130 frost free days to grow successfully. It has low drought tolerance.
Alnus incana subsp. tenuifolia grows in soils ranging from a pH of 5.5 (very acidic ranges from 5.2 to 5.5) to 7 (neutral ranges from 6.6 to 7.5). It is adapted to silt, sand, loam, clay loam, silt loam, sandy loam, loamy sand, silty clay loam and sandy clay loam soils, and prefers medium fertility.
This is a erect tree/shrub has a fast rate of growth and has a thicket forming growth form, and has an ultimate height of 9.1m / 29.9ft. The vegetative spread rate is slow.
Height at ...
- 20 years 9.1m / 29.9ft
The leaves are green in Summer.
Resistant to fire.
Fruit and seed
There is a high fruit/seed abundance beginning in Summer and ending in Autumn.
Progagation and germination
Propagation techniques include bare root, container and seed. The seed can be germinated by cold stratification / cold moist prechilling.-33°C / -27.4F to 9.1m / 29.9ft
|Scientific classifications [Edit]|
|Specific epithet ?||incana|
|Thinleaf alder (United States)|
References  ?
Plant added by plantdatabase
- People talk about 'cultivars' and 'varieties'. Here is a way to remember the difference: Cultivars are cultivated (artificially crossed and bred by nurseries and breeders) Varieties are wild (they occur naturally in nature).
- Suggest your own Tidbit