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A Nature Journal

Jack-in-the-Pulpit – a most mystical plant

It loves heavy shade and wet ground, it's relatively unaffected by insects and diseases, and it can even survive a nearby Black Walnut. It's a native perennial known as Jack-in-the Pulpit, Arisaema triphyllum, and is found in woodlands throughout most of the eastern half of the United States. Indeed, it appears in every Illinois county.

This spring wildflower grows from an underground corm in April and May to a height of 1 to 2 feet and spreads out a foot to a foot-and-a-half. Two large green trifoliate leaves, each boasting three large leaflets (up to 7 inches long and 3 inches wide), grow with long leaf stalks out of a single stem emanating from the corm. The stem and leaf surfaces are smooth and hairless. All of this sounds normal enough, but as spring continues, this plant's behavior becomes a bit bizarre, in multiple ways.

First comes "Jack" – an erect spike covered with tiny green-to-purple flowers; it's called a spadix. Then comes the "pulpit"; it's called a "spathe." The spathe is sheath-like and grows to form a hood which extends over Jack and provides shade. On the underside, this spathe or pulpit often displays white, green or purple-brown stripes.

Here it gets interesting. The plants, which flower in May and June, initially produce only male flowers. But in later years, Jack has male flowers on top and female flowers on the bottom. The term is "hermaphroditic." Those with female flowers can even trap insects. However, the Jack-in-the-Pulpits are not self-pollinating because the male flowers mature and die before the female flowers mature. The female flowers end up being pollinated by the male flowers on another plant. This lack of inbreeding apparently helps keep the species healthy. The pollination is facilitated by small flies or gnats which are attracted by the flowers' mild scent.

Jack-in-the-Pulpits can be grown from seed, but it takes perhaps four or five years before a plant flowers. The first year after a seed is planted, the plant has just a single simple leaf. The second year, the plant may have a single simple or trifoliate leaf. As a plant matures and has female flowers which are cross-pollinated, the fertilized flowers become smooth green berries, which in late summer ripen to fleshy red fruits (see photo) as the leaves wither. These fruits or berries are about a quarter-inch in diameter and appear in ovoid shaped clusters which can be up to 2 inches long. Each fruit contains one to seven small sandy-colored seeds; some woodland birds, including wild turkeys, eat the ripe berries and excrete the cleaned seeds.

Jack-in-the-Pulpits are most often found along hillside seeps in deciduous original woodlands – woodlands which are rich in organic material and have never been plowed. In addition to sexually reproducing by means of pollen transfer from male to female flowers, the plants reproduce asexually through the corm. These corms, which can measure up to 1.5" across, send out shoots early in the season to produce new plants. Thus Jack-in-the-Pulpits are generally found in colonies with a tall female plant surrounded by new smaller male plants. Beware if you're hungry, the roots contain oxalic acid and are poisonous, unless appropriately prepared.

Story by Dick Robrock (2007)