When walking near birches in the winter, you may have noticed small, flat, dark brown, four-lobed scales scattered on the snow.
Shaped like miniature fleurs-de-lis, these scales come from the conelike “fruits” or seed heads of any of the various species of birches, such as paper, sweet, silver, river, gray. Each scale has a miniscule seed attached. However, by the time you find the scale, the seed may have been eaten by a squirrel, which may also have been responsible for scattering the scales.
Birches have both male and female flowers in spring. The female flowers are tiny and greenish, in short, upright “catkins”, or narrow, dense chains. The male flowers are tiny and yellowish, hanging in longer catkins near the ends of the twigs. The catkins, fluffy with flowering, make a graceful sight among the birch branches for just a few weeks.
After the female flowers are pollinated, they develop into seeds, and the upright catkins turn into the little conelike clusters of scales that remain on the trees through the winter. Like leaf buds, male catkins form in summer and also stay on the trees in the winter, in a partially developed form, awaiting the next spring’s flowering.
Alders are closely related to birches and also have male catkins and female cones that can be found in winter. The cones are slightly different, with hard, woody scales, not so easily plucked and scattered as those of birches. The catkins are tight, shiny, and reddish-brown.
Knowing the catkins and cones of birches and alders can be a great help in learning to identify these species. They are also aesthetically beautiful and add pleasure to a winter hike in the woods.
See also Identifying Trees in Winter and Birches White, Sweet, and Silver.
