Everlasting or Seven Years Little

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Common names are a funny thing. Depending on the region, the use, and the culture, one plant can take on many names. In other situations, many different plants can take on a single name. Though it isn't always obvious to those unfamiliar with them, the use of scientific names alleviates these issues by standardizing the naming of things so that anyone, regardless of where they are, knows what they are referring to. That being said, sometimes common names can be entertaining.

Take for instance, plants in the genus Syncarpha. These stunning members of the family Asteraceae are endemic to the fynbos region of the Eastern and Western Cape of South Africa. In appearance they are impossible to miss. In growth habit they have been described as "woody shrublets," forming dense clusters of woody stems covered in a coat of woolly hairs. Sitting atop their meter-high stems are the flower heads.

Each flower head consists of rings of colorful paper-like bracts surrounding a dense cluster of disk flowers. The flowering period of the various species can last for weeks and spans from October, well into January. Numerous beetles can be observed visiting the flowers and often times mating as they feed on pollen. Some of the beetles can be hard to spot as they camouflage quite well atop the central disk. Some authors feel that such beetles are the main pollinators for many species within this genus.

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Their mesmerizing floral displays are where their English common name of "everlasting" comes from. Due to the fact that they maintain their shape and color for a long time after being cut and dried, various Syncarpha species have been used quite a bit in the cut flower industry. A name that suggests everlasting longevity stands in stark contrast to their other common name. 

These plants are referred to as "sewejaartjie" in Afrikaans, which roughly translates to "seven years little." Why would these plants be referred to as everlasting by some and relatively ephemeral by others? It turns out, sewejaartjie is a name that has more to do with their ecology than it does their use in the floral industry.

As a whole, the 29 described species of Syncarpha are considered fire ephemerals. The fynbos is known for its fire regime and the plants that call this region home have evolved in response to this fact. Syncarpha are no exception. They flower regularly and produce copious amounts of seed but rarely live for more than 7 years after germination. Also, they do not compete well with any vegetation that is capable of shading them out.

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Instead, Syncarpha invest heavily in seed banking. Seeds can lie dormant in the soil for many years until fires clear the landscape of competing vegetation and release valuable nutrients into the soil. Only then will the seeds germinate. As such, the mature plants don't bother trying to survive intense ground fires. They burn up along with their neighbors, leaving plenty of seed to usher in the next generation.

Research has shown that its not the heat so much as the smoke that breaks seed dormancy in these plants. In fact, numerous experiments using liquid smoke have demonstrated that the seeds are likely triggered by some bio-active chemical within the smoke itself.

So, there you have it. Roughly 29 plants with two common names, each referring back to an interesting aspect of the biology of these plants. Despite their familiarity and relative ease of committing to memory, the common names of various species only get us so far. That's not to say we should abolish the use of common names altogether. Learning about any plant should be an all encompassing endeavor provided you know which plant you are referring to.

Photo Credits: [1] [2] [3]

Further Reading: [1] [2] [3]

 

One Badass Moss

Badass and moss are two words that don't find themselves in the same sentence very often, if ever. Today I would like to introduce you to one moss that is certainly worth such a description. Meet Ceratodon purpureus, sometimes referred to as "fire moss." This lowly bryophyte is tough as nails and enjoys a global distribution because of it. From fires and heavy metal pollution to living in our most densely populated urban areas, this moss is a survivor. What's more, its ecology is absolutely fascinating.

Fire moss is truly cosmopolitan. It can be found on every continent and may only lose ground in the tropics where it is replaced by its close relatives. Though we often think of mosses as delicate denizens of shaded forest floors, fire moss is anything but. This is a disturbance-loving species. It gets the name fire moss for its habit of turning up in profusion following wildfires. Cleared of its competition, fire mosses growth can be quite explosive.

Being able to grow on a variety of substrates means that fire moss is equally at home in man-made habitats. It can be found growing in and along sidewalk cracks, old roofs, depressions in asphalt, and on wooden structures. What's more, it can tolerate pollution levels that would normally kill most mosses. One study found that moss grown on mine soils contaminated with toxic levels of heavy metals showed absolutely no decrease in fitness. In fact, they were indistinguishable from moss grown on clean soils.

This moss' lifecycle is ephemeral. Because it needs disturbance to persist, natural succession usually causes it to disappear from a site after a decade or two. Its spores, however, can remain viable for upwards of 16 years in the soil until fire, bulldozer, or any other large-scale disturbance opens the land again.

One of the strangest aspects of this fire moss is how it reproduces. Like all mosses, male gametophytes produce sperm that must make their way to the female gametophyte. They do this by swimming. Whereas moss species living in wet environments can let rain do the work of uniting the sex cells, fire moss has evolved a strategy more familiar to the flowering plants.

It was found that fire moss emits complex volatile scents. What's more, these scents are produced at different rates in the different sexes with females producing much more scent than males. It was found that microarthropods, specifically springtails, are attracted to these scents. Close investigation revealed that springtails significantly increased the fertilization rates in fire moss, hinting at quite a specific reproductive relationship between these organisms, both of which are representatives of some of the first organisms to ever make it onto land.

If this story has not convinced you that fire moss is one badass bryophyte I don't know what will. It is amazing to think that such an incredible organism is probably living out its life a stones throw away from where you are sitting right now.

Photo Credit: Ian Sutton (http://bit.ly/1LqqpMY)

Further Reading:
http://www.publish.csiro.au/?paper=BT9650303

http://www.nature.com/nature/journal/v489/n7416/full/nature11330.html

http://bit.ly/1U4lE2G