Erythronium seed dispersal

Nathan Lange plantsman@comcast.net
Sun, 15 Mar 2015 15:26:12 PDT

The previously cited NARGS article discusses the seed dispersal by 
ants of Erythronium species from Eastern North America. Here are a 
couple of descriptions of the Erythronium species from Western North 
America in the same article:
https://nargs.org/sites/default/…

"Western American species have seeds that are not ant-distributed and 
remain viable during
dry periods." E. revolutum is listed as an example of such a species.

"The Erythronium species of western North America have their
own, distinct method of dispersing their seeds. Their firm-walled, cup-shaped
seed capsules are held erect on tall, wiry stems, and when they are shaken by
wind or a passing animal, the seeds are hurled out as from a catapult. Not only
the capsules but also the seeds of western species are adapted to the catapult
method of seed dispersal. The seeds often must remain in the capsules for weeks
or even months, waiting for the powerful shake that will hurl them forth."

The above statements are completely consistent with years of 
observations I have made of most Western N.A. Erythronium species 
native to California, both cultivated and growing in the wild.

When observing small populations of any plant species in the wild, 
separated by what might presently seem to be insurmountable barriers 
to seed dispersion, always keep in mind that your observation is but 
one moment in time. What now appears to be individual shrubs and 
trees separated by great distances, could have very recently (within 
a few hundred years or less) been a much more continuous canopy of, 
for example, chaparral or something else, with an equally continuous 
population of Erythronium growing underneath. In a similar situation, 
it would be like finding Dichelostemma volubile growing under old 
growth chaparral in California and incorrectly concluding that this 
species only grows in shade, not realizing this species also 
frequently grows in full sun (and very well) during the years 
immediately following a summer wild fire. Understanding the ecology 
of any plant is often key to knowing its life history.

Or, maybe some seeds just hitched a ride on some passing animal, 
although a 1995 paper on Erythronium grandiflorum seed dispersal, 
another Western N.A. species, found ant and animal seed dispersal to 
be completely insignificant for this species.

Regardless, many of the lower elevation California Erythronium 
species are in full flower right now and they are spectacular.

Nathan


At 10:53 AM 3/15/2015, you wrote:
>A few years ago, when I was editing the NARGS journal Rock Garden 
>Quarterly, I received an extremely detailed article about 
>Erythronium seed dispersal, much of which we published. It should be 
>available on the NARGS website. The article is in vol. 65, p. 265.
>
>The gist, for this current discussion, is that western American 
>Erythronium species have seed dispersal by ants. As I recall, this 
>process is called "myrmecophory."
>
>As Travis wrote, some Erythronium species in the wild, especially in 
>the Pacific Northwest, occur as scattered populations of individual 
>plants, presumably by seeding. I also observed this in colonies of 
>Erythronium japonicum in Japan. In moist woodland in the American 
>west and apparently in the UK, Erythronium revolutum is particularly 
>happy to spread in this way.




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