29 September 2014
Milkweed's spectacular autumn podcast
The final stage in milkweed's life cycle is a magnificent aerial dispersal of its seeds. The dried pods, remants of those huge blossoms, crack open and several hundred aerodynamic seeds are exposed to the wind; this happens gradually, over a period of days rather than all at once, presumably to maximize the range of distribution of their landing sites.
I hope that every child (and the inner child of every adult) has had or will have the opportunity to hold a dried stem aloft and shake it gently on an autumn day. One can't help but marvel at how this immensely effective dispersal mechanism has evolved over the millennia.
Those who raise milkweed in butterfly gardens need to be aware that neighbors may not share their enthusiasm for the plant. We cut down the stems of all our plants just before the pods open. The seeds are then available for "stealth gardening" along roadsides or in wastelands.
For those who want to distribute the seeds by hand in a more controlled fashion, the seeds can be separated from the fluff (the coma), or even more simply just digitally removed from a mature but unopened pod (instructive video here).
(and yes, I know it's actually a "seedcast," not a podcast, but I couldn't resist using the word)