30 Birches Birch is another local climax species. Yellow birch (Betula alleghaniensis) has bronze-colored bark which peels off horizontally in narrow curling strips. Known as “widow makers,” apparently healthy yellow birch trees may be dead inside and will be blown down easily. The bark of the black birch (Betula lenta) is dark reddish brown or black and does not peel. There are wide lenticels, reminiscent of young cherry trees. Broken twigs smell and taste like wintergreen. The oil extracted from the twigs has been used to flavor the drink birch beer. Birch leaves are oval and doubly toothed, similar to those of musclewood and ironwood. The buds of both birches grow on top of short spurs, a characteristic that distinguishes these from cherry trees. The fruits of both birch species are cone-like and grow upright from the stem. 31 Climax Forest The understory trees here are primarily the seedlings and saplings of the dominant trees that form the forest canopy. This is one of the best pieces of evidence that this forest is at the climax stage of development. The climax species will reproduce themselves indefinitely until the environmental conditions change. What factors in the environment might alter the climax forest community? Recall #4 and #12 for some examples. 32 Interrupted and Hay-scented Ferns Several clumps of interrupted ferns (Osmunda claytonia) can be found here. The fronds grow up to six feet and possess regions of smaller spore-bearing leaflets, giving the frond an interrupted appearance. Hay-scented fern (Dennstaedtia punctilobula) is a sun-tolerant species which smells like freshly cut hay. The fronds are lacy and bear spores on the undersides. Which other fern also possesses these two characteristics? (See #8.) Return to the main trail and walk to the edge of the forest. The trail continues up the hill. 33 Field Wildflowers of Summer and Fall Queen Anne’s Lace or wild carrot (Daucus carota) is common to open fields. The many tiny white flowers are arranged in an umbel. The garden carrot was developed from this species. Dame’s rocket (Hesperis matronalis) is one that escaped from gardens and grows as an alien in the wild. Its pink flowers can be found commonly on the edges of woods in early summer. Butter-and-eggs (Linaria vulgaris) takes its name from the yellow and orange color of the clustered, irregularly-shaped flowers. Musk mallow (Malva moschata) grows up to two feet in height and blooms all summer. The five-petaled flowers are pink, white, or sometimes bluish and may be two inches in diameter. Do you smell the faint musk odor of the flowers? 34 Northern Arrowwood (Viburnum dentata) This shrub has smooth, gray bark. The remarkably straight twigs have been used for the shafts of arrows. The opposite leaves are oval with ruffled edges. Clusters of small flowers that bloom in early spring develop into black fruit in late fall. 35 Trapping Insects Using Deceit Look for spider webs in the open field in summer and early fall. You may find some webs decorated with thread more thickly laid in the form of patterns. The thread reflects ultraviolet light which insects can easily see, and the patterns designed by the spiders resemble flowers. Pollinating insects are attracted to the web, caught, and devoured by the wily spider. Try placing a fly or small beetle on a web and observing the spider’s behavior. 36 The Aster Family Many summer and fall wildflowers are members of the aster family. The flowers are composite; that is, there are many individual flowers on each base or receptacle. For example, each oxeye daisy (Chyrsanthemum leucanthemum) has hundreds of tiny yellow disk flowers surrounded by 20 or more white ray flowers. These are not petals, but entire flowers. Other members of the aster family include New England aster (Aster novae angliae) with yellow disk flowers and purple ray flowers and black-eyed Susan (Rudbeckia hirta) with chocolate-colored disks and orange ray flowers. Chicory (Cicorium intybus) has only ray flowers which are light blue. The roots of chicory may be ground, roasted, and used as a coffee substitute. 37 Shadbush (Amelanchier canadensis) This shrub has pale gray bark with black vertical streaks. The pointy buds are beech-like. The fruits are small, sweet-tasting red or purple berries. The berries are eaten by 27 species of birds. The birds serve to disperse the seeds when they pass the undigested seeds out of their bodies. Shadbush takes its name from the fish. The white flowers blossom in the spring at the same time as the shad run up the rivers. Around Mother’s Day in May, the pink flowers of fringed polygala (Polygala paucifolia) can be found in abundance on the three- to six-inch plants in this area. 38 Butterflies The flowers of the open field attract a multitude of butterflies. In one five-hour period in July, 32 species of butterflies were recorded in this field. Ones commonly seen include the monarch, mourning cloak, and great spangled fritillary (see cover illustration). The larvae of the monarch feed on milkweeds, those of the fritillary feed on violets, and those of the mourning cloak feed on willows. Which plants are the adults most attracted to for nectar?