The number three dominates the sedges throughout their organization. It occurs repeatedly, or is traced obscurely, in their flowers, for they are lily-kin. Inferentially the ancestors of all the sedges had three pistils, or a single pistil dividing into three stigmas, three stamens, or six, in two trios, three petals, and three sepals. They were, in many respects, like the rushes of today.
But their descendants have departed, more or less widely, from the ancient family traditions. For some species have but two stigmas, whole groups have two stamens, or manage to get along with one, and two tribes bear stamens in one flower and pistils in another.
Sedge-blossoms grow in spikes, clumps, or clusters, massed together so closely that their calyxes and corollas, when they possess any, are utterly ineffective.
But as the wind is their sole messenger, nowadays, there is no reason why they should allure and charm insects, as their ancestors may have done in the days of old. The florets, like those of the cat-tail flags, have undergone a change of form in connection with changed circumstances. In those sedge-flowers which bear stamens only, the calyx and corolla, no longer needed for any purpose, have vanished utterly away.
But the sepals and petals of the perfect floret borne by many sedges have had another job offered them by Nature, and have saved themselves from extinction by acquiring usefulness in a new capacity. In process of time they have become adapted to aid in the great work of seed distribution.
One of the stateliest of native sedges is the so-miscalled "wool-grass," which is a conspicuous object in wet fields during the latter summer. The large and graceful tassel of bloom is composed of innumerable soft, brown lumps, not much larger than grains of barley. If we pick one of these apart, under a lens we shall find that it is a compact mass of overlapping scales (Fig. 52).
Under each scale is a single flower, with three stamens, and a long, slender pistil dividing into three stigmas.
By August the stamens have withered away, after accomplishing their life-work. The pistil has done its work, too. It is now a fruit, ripe and ready to travel, for around it are six long hairs, which are the petals and sepals, altered over into a flying apparatus. In the "beak-rush," which we may find growing near the "wool-grass," calyx and corolla have undergone an equally great but wholy different adaptation.
Fig. 52. - From low-lying fields.
I, "Wool-grass " (Eriopharum cyperinum); 2, the fruit with surrounding hairs; 3, "beak-rush" (Rhynchospora glomerata); 4, a cluster of flowers and scales of the "beak-rush"; 5, its ripe fruit with accompanying bristles.
They are converted into barbed bristles, which catch hold where and when they can, and thus help the seed along in the world.
The calyx and corolla of the pretty "cotton-grass" are changed, like those of the "wool-grass," into long streamers, which lengthen as the seed matures, and become a tuft of creamy filaments, an inch or two in length. They make this sedge a conspicuous and beautiful object in low-lying fields, when olive and bronze shades begin to replace the vivid greens of the earlier year (Fig- 51).
The true "bulrush" and the "spike-rush" (Fig. 51), which are both sedges, in spite of their misleading names, have adopted the beak-rush's plan, and changed their petals and sepals into toothed bristles, which look, through the microscope, like narrow saw-blades.
Most of our native sedges belong to one great group, the genus Carex. Its various members generally grow in moist places and blossom in the spring, so that their seeds are set, and often ripened, too, by midsummer.
"A carex" can be recognized afield by the tyro, but the correct identification of the particular carex in question is quite another matter. For the species are so difficult to distinguish one from another, vary so perplexingly, and blend into one another so confusingly, that they can confound the experienced naturalist. In most carices the stamens and pistils are borne in separate flowers, which grow upon the same plant.
In one large section of them the two kinds of flowers grow on the same spike, which is staminate at its apex, and pistillate below, or, as Tweedle-dee was wont to remark, "contrariwise"
In another large section the staminate flowers grow in a spike by themselves, at the tip-top of the sedge, while the pistillate blossoms, in modest groups, occupy lower places (Fig. 53).
Each flower of either sex is sheltered and almost concealed by a green scale. The staminate flowers have no calyces nor corollas at all, not even reminiscent ones of saw-blades or bristles.
Fig. 53. - A typical carex (Carex hystricina).
1, A staminate flower with its scale; 2, a pistellate flower with its scale; 3, cross-section of the perigynium, showing the fruit within. (All magnified).
Each is reduced to its lowest terms, and is merely a trio of stamens.
Its flower-affinity consists of a pistil, borne on a short stalk, and partly or completely surrounded by a tiny green bract. The pistil forks at its tip into two or three long stigmas, which reach over the tiny bract close to them and the larger scale below and wait for the pollen messages which the wind will bring to them from other sedges. After the pollen has come, the stigmas, having served their purpose, wither away. At about the same time the tiny bract which has invested the pistil increases greatly in size, and by latter summer it becomes an inflated flask-shaped sac, enclosing the ripening fruit. This sac is known as the "perigy-nium," and is one of the distinguishing marks of the Carex family. Some botanists regard it as the sepals and petals of the sedge-flower, joined together, and altered out of knowledge.
Inside the perigynium there is a hard lens-shaped or triangular body, which we should incline to call a seed. But, small though it be, it is the ripened ovary, and hence a fruit.
The sedges, unlike the grasses, are a useless family. They are of small value to man, and their leaves and stems contain so little nutritious matter that they are seldom eaten by grazing animals. Indeed, in the whole great family of two thousand species there are but three useful members.
The chufa, a native of the Mediterranean shores, is sometimes cultivated for the sake of its small, sweet tubers.
Another sedge, the Cyperus textilus, is used in India for making ropes and mats. It is nearly related to the most useful and celebrated of all the sedges - the Cyperus papyrus, or paper-reed of old Egypt. The Hebrew name for this plant occurs in the Old Testament account of the hiding of the infant Moses, and has been rendered "Bull-rush" in the English Bible.
This sedge provided cheap and convenient writing material for the ancient world. "Papyrus," says an excellent authority, "was made of the inner cuticle of the stalk, which was separated into thin strips. These were laid side by side, with another layer of strips crossing them at right angles. The two layers, thus prepared, were soaked in water, then pressed together to make them adhere, and dried. For books the papyrus was formed into rolls, by cementing together a number of sheets".
The manufactured papyrus was called "papu" by the Egyptians, and hence our word paper. Herodotus calls it byblis, whence the Greek "book" and our "bible".
So sedges, in their humble way, have helped to pass the treasures of thought and learning onward through the ages, and as the life, mental and spiritual, is more than meat, they have not been so far behind the grasses in real serviceableness after all.