observer. Note the undergrowth in woods or under trees (Fig. 10). Observe that in pine and spruce forests there is almost no undergrowth, partly because there is very little light.
On the same area the societies may differ at different times of the year. There are spring, summer, and fall societies. The knoll which is cool with grass and strawberries in June may be aglow with goldenrod in September. If the bank is examined in May, look for the young plants that are to cover it in July and October; if in September, find the dead stalks of the flora of May. What succeeds the skunk cabbage, hepaticas, trilliums, phlox, violets, buttercups of spring? What precedes the wild sunflowers, ragweed, asters, and goldenrod of fall?
The Landscape.—To a large extent the color of the landscape is determined by the character of the plant societies. Evergreen societies remain green, but the shade of green varies from season to season; it is bright and soft in spring, becomes dull in midsummer and fall, and assumes a dull yellow-green or a black-green in winter. Deciduous societies vary remarkably in color—from the dull browns and grays of winter to the brown greens and olive-greens of spring, the staid greens of summer, and the brilliant colors of autumn.
The autumn colors are due to intermingled shades of green, yellow, and red. The coloration varies with the kind of plant, the special location, and the season. Even in the same species or kind, individual plants differ in color; and this individuality usually distinguishes the plant year by year. That is, an oak which is maroon red this autumn is likely to exhibit that range of color every year. The autumn color is associated with the natural maturity and death of the leaf, but it is most brilliant in long and open
