Arums, Orchids and Vines, Oh My!

This week we head into the forests of Illinois to see what late spring botany we can find. This is one of the coolest times of the year to look for plants in temperate North America. 

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Matt Candeias (

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Grant Czadzeck (

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Artist: Lazy Legs
Track: Molasses
Album: Lazy Legs EP

Spathiphyllum - A Natural Perspective on a Common Houseplant will never take peace lilies for granted again. As many of you reading this can empathize, I have up until this point only encountered these plants as sad looking additions to a dark corner of the home or office. Their ease of care has earned them the honor of living among even the least botanically inclined. Though we call them peace lilies, these plants are not lilies at all. They actually belong to the family Araceae, which makes them distant relatives of plants like Jack-in-the-pulpit.

All peace lilies belong in the genus Spathiphyllum. There are something like 40 different species that grow in tropical regions of Central and South America as well as southeastern Asia. As horticultural specimens, they aren't difficult. Modest light and the occasional watering are about all these plants need. Like all house plants though, I have wondered about how these plants behave in the wild.

During a trip to Costa Rica, I was very fortunate to observe some interesting behavior. Wild growing Spathiphyllum inflorescences have a scent. You would never know this based on the plants you find for sale at the local nursery. Like many roses, it would seem the their natural floral scent has largely been bred out of captive individuals. This scent is obviously meant to attract pollinators, however, the type of pollinators being targeted came as quite a surprise.

As I looked over a large patch of flowering Spathiphyllum, I was flabbergasted when I realized just what was visiting the spadix - Euglossine bees! Euglossine bees are collectively referred to as orchid bees ( This is because the males require specific scent compounds to attract females. They do not produce these compounds naturally. Instead, they must collect them from the flowers of orchids such as Stanhopea, Gongora, and Catasetum.

Well, as it turns out, orchid bees also collect scent from the spadix of Spathiphyllum blooms! The whole while I was watching this group of plants, multiple Euglossine bees paid a visit. What was most exciting is that many of the bees had orchid pollinia stuck to their backs. This was evolutionary ecology in progress and I was witnessing it first hand!

Its a real shame that we have altered captive Spathiphyllum in such a way that they do not produce scent. The smell is heavenly to say the least.

Further Reading:

A Case of Sexual Fluidity in the Plant World


In humans, sex is determined at fertilization. The embryo receives either an X or a Y chromosome. Many other organisms have their sex determined in a manner similar to this as well. The case with plants is not so rigid. Many plants produce both male and female parts on the same flower, others have flowers that are either male or female, while some can change their sex throughout their lifetime. The latter is quite interesting and offers an insight into the differences in maleness and femaleness. 

The green dragon (Arisaema dracontium) is an arum related to jack-in-the-pulpit. It is wide spread throughout the east but declining in much of its northern range. This species produces a single inflorescence that can be purely male, both male and female, or, in some rare cases, entirely female. The mechanism for this has been a subject of interest for many botanists as it does not seem to be dictated solely by genetics. It has been discovered that any given plant may switch up its flowering strategy from year to year.

What researchers have found is that male flowers are most often produced in younger plants as well as plants that are stressed. In years where environmental conditions are not as conducive to survival or if the plants have not had enough time to build up energy reserves, it is not uncommon to find only male plants. This is advantageous since male flowers and pollen are a lot less costly to produce than ovaries. Also, the plant does not have to allocate resources into developing seeds. In good years and also in older, larger plants, inflorescence are produced that are both male and female. If the plants are less stressed and large enough, more energy can be allocated to seed production. In some rare cases, very large plants have been known to produce only female flowers. This seems to be a strategy that is adopted only under the best of conditions. 

It should be noted that whereas there seems to be a threshold for environmental conditions as well as plant size in determining what kinds of flowers will be produced, each green dragon population seems to vary. In essence there is some genetic determination for how the plant will respond in any given year but this is where teasing the gene environment out of the actual environment gets tricky. Studying these plants is giving us more insight into the advantages and disadvantages of each sex as well as helping to inform how sensitive species like the green dragon will respond in a changing climate. 


Further Reading:

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.

Further Reading: