(First upload on September 6 2008. Last on December 9 2020) [ 日本語 | English ]

Alnus japonica (Thunberg) Steud.

Mount Usu / Sarobetsu post-mined peatland
From left: Crater basin in 1986 and 2006. Cottongrass / Daylily

Alnus Mill. (ハンノキ)
Hannoki (ハンノキ, 榛ノ木), Japanese alder
Yachihannoki (ヤチハンノキ, 谷地榛ノ木), commonly called
Life form: deciduous shrub-tree
Distribution: East Asia (China - Japan)
Habitat: wet lowland (fen) ⇒ wetland (湿原)

Field training on integrated environmental research (統合環境調査法実習)

Pollen allergy (花粉症): a small amount of pollens dispersed in early spring → person who has alder pollen allergy has high risk to develop white birch pollen allergy
var. arguta Call., or f. arguta (Regel) H. Ohba (エゾハンノキ)
var. koreana Call., f. koreana (Callier) H. Ohba (ケハンノキ), dense auburn hair on young shoots and leaves
var. formosana (Burkill) Callier (タイワンハンノキ)

Alnus japonica in Hokkaido

Alnus1 Alnus2 Alnus3
Alnus4 Alnus5 Alnus6
Alnus7 Alnus8
[1] close-up of female inflorescences (see males of A. maximowiczii). [1/2] at a forest edge near Utonai Lake on June 11 2008. [3] in Makunbetsu Swamp (マクンベツ湿原) on April 24 2010. [4] along Sakushukotoni River in the experimental farm of Hokkaido University, Sapporo, on July 28 2017. [5/6] along a stream near Onnenai Visitor Center in Kushiro Moor, eastern Hokkaido, on July 2 2014. ⇒ a giant tree (巨木) in Yachidamo Park (Yachidamo = Fraxinus mandshurica), N28E4, East Ward, Sapporo, on May 6 2015. [7] in Shiretoko Five Lakes Aera, eastern Hokkaido, on August 29 2020. [8] along Tonneusu Pond (トンネウス沼) in the North Ward of Sapporo on November 7 2020.