Arisaema triphyllum

 

Jack and Jill

 

When it comes to reproduction, the jack-in-the-pulpit has several options.  It has the ability to reproduce asexually as well as sexually. 

The plant's asexual means of reproduction involves the jack-in-the-pulpit's corm, which is an underground, bulblike stem.  The corm produces "cormlets", underground buds which will form into new plants.  Find out what else a corm is used for on the nutrition page!

The jack-in-the-pulpit uses a unique method of sexual reproduction known as sequential hermaphroditism.  In this mode, any given plant could be male, female, or both.  The environment of each plant determines its gender.  For example, when things are going well for the jack-in-the-pulpit and the environmental conditions are right, a plant is more likely to produce female flowers.  These flowers are not the spathe, which all jack-in-the-pulpits possess, but actually extremely small flowers, which are located inside the spathe at the base of the spadix.  You can see a picture of a female flower off to the right.  Conversely, in times of environmental stress, the jack-in-the-pulpit will revert to its male form in the following growing season.  Male flowers are located in the upper spadix and are much smaller than their female counterparts.  A picture of some male flowers is below.  The pictures on this page and several others were provided by Wildwood Park web manager Gary Cote.  To see their home page, click here or to view their Species of the Week page on Arisaema triphyllum, click any of the pictures.

Female jack-in-the-pulpits produce fruits, so it takes more energy to be female rather than male.  This is why stressed plants will revert to the male form.  In times of extreme need, a plant may even change into a vegetative state.  This vegetative state is used by the plant for the first four to six years of its life.  This form of the plant cannot create male or female flowers and therefore cannot reproduce.  While this does seem counterproductive at first, the use of sequential hermaphroditism does have its benefits.  It secures that only plants that are large enough and in "good enough condition" are able to reproduce.  Sequential hermaphroditism also inhibits self-fertilization.

Jack-in-the-pulpits flower during the early part of summer and the fruits are produced later in the summer.  The berries are attached to the stalk of the spadix where the female flowers had been.  They begin green in color, but by autumn, they become bright red.  The fruits are actually the plant's ovaries and can carry up to six ovules.  The ovules hold the seeds themselves, but often contain only one or two seeds.  The low number of seeds produced causes the jack-in-the-pulpit to have a slow distribution rate.

The jack-in-the-pulpit's reproductive cycle isn't the only interesting thing about it.  Head over to the interesting facts page to learn more!