Virtual Museum of Canada
Jardin botanique de Montréal 
Centre for Forest Research

Extended work hours

Although most conifers retain their needles and scales in winter, they cannot perform photosynthesis (Synthesis of organic substances made by plants from the light energy.) when there is no water available in the frozen ground. However, conifers with evergreen foliage do have one substantial advantage over caducous (Qualifies leaves or organs detach themselves and fall from a plant. ) trees.

In fall, they continue photosynthesis for a few more weeks after broadleaf trees lose their leaves. And in spring, they also have a head start on their competitors, which lose valuable time regrowing their foliage. The closer you get to the poles, the shorter the growing season, and the more advantageous these additional hours of photosynthesis are for conifers.


Photo of scales of a white cedar (Thuja occidentalis)
Thuja occidentalis
© Jardin botanique de Montréal (Gilles Murray)
Previous picture1  2  3  4  5  6  7  8