Geranium maculatum. Everyone knows “geraniums,” but few know real geraniums. The showy, aromatic plants of gardens and flower boxes are distant cousins from Africa. The real thing grows in our own backyard, the common and widespread Wild Geranium. Geranium means “crane” — the flowers are often called cranesbills. The names refer to the shape of the seed case, which has been likened to the long beak of the namesake bird. When the seeds inside are ripe, the long pod pops and catapults them into the air. The mechanism that propels the fruit consists of the five sides of the beak. As the pods dry, they become tense, stretched springs. When the time is right, they simultaneously uncoil, hurling the seeds up to 30 feet and leaving behind a whorl of curls. Such propulsion helps ensure the spread of the plant into new, but nearby territories, usually with similar soils and the right light. However, when it lands, the seed’s trip has not ended. Each has a “tail,” called an awn, which curls when it is dry and straightens when wet. Botanists suspect this tail-twisting motion propels the seed very slowly a short distance along the ground until it becomes stuck in a small hole or crevice. At that point, the motion may help push the seed into the soil. This amazing ability to “crawl” into a protected spot may help the seed find a suitable place to eventually germinate while escaping the birds and small mammals that might spot and eat it.