The Arisaema Complex

If you live in the east, Jack-in-the-pulpit or Arisaema triphyllum, is most likely an unmistakable part of late spring. Being a member of the arum family, the bracts of the plant form a tube and hood over the spadix and flowers. This is a highly variable species, in fact, there are at least 4 recognized subspecies that make up the Arisaema complex, A. triphyllum ssp. pusillum, A. triphyllum ssp. quinatum, A. triphyllum ssp. stewardsonii, and A. triphyllum ssp. triphyllum.

Interestingly enough, each subspecies seems to be reproductively isolated from the others. Each also seems to prefer its own habitat. For instance, triphyllum, a denizen of rich woods, blooms after the last frosts while stewardsonii, a denizen of swamps and bogs, blooms a few weeks later. Another interesting aspect of this complex is that pusillum and stweardsonii are both diploid plants, having 28 sets of chromosomes each, whereas triphyllum, our most common subspecies, is believed to be a hybrid of the two and is tetraploid and thus has 56 sets of chromosomes. Some would argue that these plants should be treated as distinct species since the characteristics that designate each subspecies seem rather specific but all across their range, there are many plants that seem to blur the lines. This is a debate that is only going to be solved by more accurate DNA analysis. However, nature doesn't seem to be reading any science texts and therefore rarely falls into our neat, clear-cut mindsets.

Being an arum, this species does produce some heat as well as an odor. The flowers produce a smell reminiscent of mushrooms and indeed, this is to attract their main pollinators, fungus gnats. Next time you come across a blooming Jack-in-the-pulpit, get down and take a whiff. It isn't necessarily good or bad but either way it is an experience. This species is gaining some traction in the gardening community as well due to its ease of care and unique appearance. It is also easy to establish from seed, however, make sure to wear gloves and avoid any skin contact while de-fleshing the seeds because being that it is a member of the arum family, this species produces calcium oxalate crystals that can cause severe burning.

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