The Carlisle Mosquito Online

Friday, October 17, 2003


Biodiversity Corner Jack-in-the-pulpit

(Photo by Kay Fairweather)

Name: Arisaema triphyllum or Jack-in-the-Pulpit. It is also known as Indian-turnip because the starchy corms were cooked and eaten by native Americans. The Massachusetts Poison Control System includes it on their list of poisonous plants at www. If eaten raw, it causes severe irritation to the mucous membranes of the mouth and throat and the lining of the stomach due to the calcium oxalate crystals in it.

When and where seen: The photograph of the berries was taken on October 11 on the Chelmsford side of the Cranberry Bog. In spring, I have seen it flowering along the Rockstram Trail from School Street to the Estabrook Woods.

Identification: Jack-in-the-pulpit is easily identified in the fall by the cluster of bright red shining berries on a stalk about a foot tall, or lying on the ground. In spring you can recognize it by the green, cylindrical, hooded chamber called a spathe. Inside, the spathe is marked with vertical stripes of green and purplish-brown. If you lift the hood, you will see a slender rod inside called a spadix. The flowers are attached to the spadix. The plant usually has a single stem with two compound leaves. As you might guess from the species name, triphyllum, each leaf is divided into three leaflets. The name Jack-in-the-pulpit came into use in the mid 1800s; the spadix is Jack the preacher; his pulpit is the spathe. He preaches to a congregation of insects from late April up through June after which time his pulpit gradually deteriorates and eventually drops away. If the flowers were fertilized, all that remains of Jack is the cluster of berries.

Habitat: Jack-in-the-pulpit likes rich moist soil and shade. It is an attractive plant for a woodland garden but do not harvest it from the wild. You can get them from Blanchette Gardens on Rutland Street. There are several species of Arisaema, some with unusual colors and shapes in the spathe and spadix.

Drawing by Norma Japp
References: Carol H. Woodward and H. W. Rickett, New York Botanical Garden's Field Guide to Common Wildflowers of the Northeastern United States; Donald Wyman, Wyman's Gardening Encyclopedia.

Submissions for the Biodiversity Corner are encouraged from everyone. What about a bat or a spider for Halloween? Send to Kay Fairweather at 392 School St, Carlisle MA 01741 or to

2003 The Carlisle Mosquito