Forest Preserve District of Cook County, Illinois
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The Arums
Nature Bulletin No. 711   March 30, 1963
Forest Preserve District of Cook County
Seymour Simon, President
Roberts Mann, Conservation Editor

Two of our best-known spring wildflowers are the Skunk Cabbage and the Jack-in-the-Pulpit. They are members of the Arum family and have a curious structure characteristic of this interesting family. Instead of petals, there is a single enclosing sheath with a canopy-like top, called a "spathe". This encloses and protects a fleshy club-shaped spike called a "spadix". The spadix appears fuzzy because it is crowded with tiny flowers that have no petals and no sepals.

The Arum family includes more than 1000 species -- most of them tropical; most of them having large coarsely-veined leaves and large fleshy rootstocks; most of them found in swamps, ponds, and moist habitats. Many have a bad smell, or a biting taste, or both. A cruel prank sometimes played on a child in the woods is to offer him a bite of Indian Turnip, another name for the Jack-in-the-Pulpit. The white starchy underground root has a pleasant taste, at first, but in a few moments his mouth and tongue begin to smart, and this burning sensation becomes an agonizing pain which lasts for many hours.

The leaves, roots and the small bullet-like seeds of the skunk cabbage produce a similar burning, though not so severe. The Indians, however, used the roots of both these plants extensively for food or medicines, and also the tuberous roots of some other wild arums: the Sweet Flag -- a shore plant which furnishes a noted aromatic drug, the Water Arum or Wild Calla, and the Golden Club. Continued boiling, heating, or thorough drying destroys the toxic effect. The Indians baked the roots in pit ovens for three days and stored them for winter food.

The Arum family includes a familiar garden flower, the Calla Lily, native to Africa; and also the Elephant Ear with its enormous shield- shaped leaves, which comes from the East Indies. The large starchy roots of the Taro, a close relative of the latter, are an important food in Hawaii and the Pacific Islands. Another arum, a native of tropical America but often grown in greenhouses, is the Ceriman, or Monstera: a climbing evergreen vine which grows by aerial roots, has a peculiar edible fruit, and has huge deeply-cut leaves perforated by numerous holes. The largest flower in the world -- the Krubi of Sumatra -- is an arum. Its huge vase-shaped spathe, 6 to 8 feet in diameter and equally high, is yellowish on the outside and rich purple in the throat. The yellow tubular spadix arises from it to a height of 15 feet or more, and the flower has a powerful fetid odor.

The skunk cabbage blooms long before any other spring wildflower, in swampy or spring-fed places. The hood-shaped spathe, maroon streaked with greenish-yellow, is open on one side. Inside is the lavender club-shaped spadix about the size of a marble. Its carrion odor attracts bees, flies and gnats which pollinate it. The large leaves, which appear later and grow to the size of rhubarb leaves, have this same disagreeable smell when bruised.

The Jack-in-the-Pulpit grows from 12 to 30 inches high in our moist woodlands and has one, two or more broad leaves each divided into 3 leaflets. The flower which rises from the fork of the leaf stems, has a spathe which curls over to form a canopy for "Jack", the spadix, who stands inside. The spathe is green, striped with purple or brown depending upon the amount of shade. Many insects are trapped inside it. The flower is followed by a large close cluster of green berries which become brilliant red in autumn. The green dragon is similar except that it has a single leaf with 5 to 17 slender leaflets arranged in a semicircle, a rolled-up pointed spathe, and a long whip-like spadix.

Most arums are aromatic.

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