many species of trees in a form that brings to mind the graceful trees
on a blue willow plate.
Trees with catkins include those of the Beech family (oaks,
chestnuts), the Willow family (willows, aspens, poplars, cottonwoods),
the Birch family (birches, alders, hornbeams), the Mulberry family,
and the Walnut family (walnuts, hickories). In the Willow family, both
male and female flowers occur in the form of catkins, and for most
species, a given tree has only one type, either male or female. In the
Willow genus (Salix species), many catkins are small and upright,
while cottonwoods and aspens have drooping catkins.
The catkins shown on the card on birch trees I Finland. This lovely
card was sent to me by my dear friend Pia.