Leaf and unripe nuts. Mustio, Inkoo, Finland. Planted. 2010-07-25.

Male flowers hanging down. Botanical garden Kaisaniemi, Helsinki, Finland. Planted. 2007-04-02.

Nuts: three stolen (or fallen), one left. Botanical garden Kumpula, Helsinki, Finland. Planted. 2006-09-09.

Next year's male catkins, all ready and green. Botanical garden Kumpula, Helsinki, Finland. Planted. 2006-09-09.

Green nuts. Mustila arboretum, Elimäki, Finland. Planted. 2006-07-11.

Female (red) and male (yellow) flower on a twig. Perheniemi, Finland. Wild. 2006-04-27.

Flower, hanging down. Botanical garden Kaisaniemi, Helsinki, Finland. Planted. 2006-04-22.

Branch in flower. Botanical garden Kaisaniemi, Helsinki, Finland. Planted. 2006-04-22.

Branches in flower. Botanical garden Kaisaniemi, Helsinki, Finland. Planted. 2006-04-22.

Female flower. Oulunkylä, Helsinki, Finland. Wild. 2005-04-15.

Branch in male (tiny red) and female (yellow catkin) flower. Oulunkylä, Helsinki, Finland. Wild. 2005-04-15.

Flowers, male (hanging, yellow) and female (small, red) Perheniemi, Iitti, Finland. Wild. 2004-04-19.

Shrub in flower. Oulunkylä, Helsinki, Finland. Wild. 2002-03-31.

Male (hanging, yellow) and female (sessile, red) flowers. Oulunkylä, Helsinki, Finland. Wild. 2002-03-31.

Trees in flower. Oulunkylä, Helsinki, Finland. Wild. 2002-03-31.

Branch with green nuts. Mustila arboretum, Elimäki, Finland. Planted. 2000-07-03.

Flowering bush. Helsinki, Finland. Wild. 2000-05-01.

Flowering branch. Helsinki, Finland. Wild. 2000-05-01.

Closeup of flowers. The females are those small red tufts, the male is letting it hang and get blown away. Helsinki, Finland. Wild. 2000-05-01.