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Posts tagged “Arisaema triphyllum

Jack & Jill-In-The-Pulpit

There are both male and female Jack-in-the-Pulpits, and nutrition determines which gender a given plant is.  For the first year or two, every Jack-in-the-Pulpit bears male flowers.  Then the amount of nutrients the plant takes up begins to influence the sex of the plant.  Females flowers produce seeds, and it takes a considerable amount of nutrients to do so.  Thus, if there’s an abundance of nutrients one summer, a plant is female the following summer; a lack of nutrients produces male Jack-in-the-Pulpits the following year.

While the flowers themselves are very distinct (females are green knobs, males are threadlike and not green), it can be hard to see them, as the spathe (pulpit) wraps around the spadix (Jack) which bears the flowers at its base. You can often guess the sex of a Jack-in-the-Pulpit by the number of leaves it has. In general, female plants produce two leaves, whereas male plants usually have only a single leaf.  If nutrients are really lacking, the plant typically produces a single leaf, but no Jack or pulpit. (Photo:  female Jack-in-the-Pulpit on the left; male Jack-in-the-Pulpit on the right).

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Jack-in-the-Pulpit Fruits Maturing

jack in pulpit fruit 022After the spathe (hood) dies back, Jack-in-the-pulpit fruit is more obvious, especially as the green berries turn brilliant reddish-orange at this time of year. Eventually the stem withers and the seed head falls to the ground. The tissues of Jack-in-the-pulpit, particularly the roots, contain high toxic levels of oxalic acid. The berries, if eaten, cause a burning sensation in the mouth and throat due to physical cuts caused by the crystals of calcium oxalate. Although cattle, goats, pigs and sheep are susceptible to the toxin, white-tailed deer, wild turkeys and wood thrushes appear to consume them without distress. As is obvious from this photograph, though, the berries are not in high demand.

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Jack-in-the-Pulpit Corm: A Black Bear Delicacy

5-23-13 jack-in-the-pulpit corm 069When black bears first emerge from hibernation, they survive mainly on emerging green vegetation in wetlands. As the season progresses, there are more and more food options to choose from, including a favorite – the corm, or underground bulb-like storage structure, of Jack-in-the-Pulpit. Even though they are large, somewhat lumbering creatures, black bears dig up and remove these corms as if they had a tiny tool designed just for this purpose. They barely disturb the earth, leaving only very small holes as evidence of their presence. A friend of mine witnessed this just outside his window one spring day, and could not believe the delicacy with which the bear extracted these morsels of food from the ground. Apparently the calcium oxalate crystals in Jack-in-the-Pulpit that cause the burning sensation in human mouths doesn’t affect bears, at least not enough to protect the plant.

Jack-in-the-Pulpit Corms

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Jack-in-the-Pulpits have underground, vertical swollen stems referred to as corms, which store nutrients that allow them to withstand extremes in temperature, as well as droughts. They also provide the plant with the energy it needs to produce leaves and flowers. A large corm is likely to produce a female plant (which needs more energy to produce seeds), a smaller corm a male. If the plant lacks enough nutrients to produce a flower, its corm will be very small. All parts of Jack-in-the-Pulpit, including the corm, contain a high concentration of calcium oxalate crystals, which are known to cause a burning sensation if eaten. Native Americans roasted or dried Jack-in-the-Pulpit corms (Indian Turnip or Iroquois Breadroot, as they called it) before grinding them into flour for bread, using them to treat colds or as a contraceptive. There is still a demand for their corms today, but it is not from humans – black bears find them irresistible!  NOTE: An alert reader suggested that I emphasize the fact that of Jack-in-the-Pulpit is NOT to be eaten by humans.  The crystals in it bear many sharp needles that cut and poison the flesh, and if bits of the plant get to the back of your mouth, it can cause it to swell to the point of suffocation!