Deciduous trees like birch and aspen also occur in the boreal forests, but the early spring growth of the evergreens allows them to overtop and dominate the deciduous trees. Plants like bilberry and sphagnum moss grow when enough light reaches the ground. The great providers The conifer trees are fundamental to the boreal food chain. Moth and sawfly larvae eat the needles. Other insect larvae, including those of the wood wasp and pine sawfly, attack the wood itself.
Capercaillies eat the conifer needles during winter, when food is to short.
To crossbills and red squirrels, conifer seeds are important dietary elements. Caribou and reindeer, which migrate south from the tundra to spend the winter in the shelter of the forest, depend upon scraping away the snow beneath the trees to find lichens and other vegetation. Small rodents such as voles feed on bark, buds, fungi seeds and berries. During spring and summer in the boreal forests, insects are abundant, and they attract large numbers of migratory birds to the habitat to breed. The abundant voles and other small mammals are the prey of the red fox and the great grey owl.