Seed Dispersal

Richard richrd@nas.com
Mon, 23 Sep 2013 16:18:19 PDT
As I have been collecting lily seed pods this fall just ahead of the rains and the early snowfall in the Cascades of Washington and Oregon, it  is interesting there always seems to be some seed left in the pods no matter how long since mature. Dispersal mechanisms is an old scientific study thread of my own as I spent  a good bit of time looking at spore dispersal in mushrooms, and plant disease fungi. 

Some pods will pop open forcibly spreading the seeds but in the lily there is an adaptive advantage to dole out it's seeds out over time. 
I googled this topic of seed dispersal in lilies and came up with a botany manual for students written by William James Beale in 1898. "Seed Dispersal, William James Beal, 1898, (scanned by google books)"

Here he explains (i had to slightly edit the scan)

"Ripened pods of lilies usually stand straight up on a stiff elastic stem .( FiG 33) At the left a dry fruit of a lily opening to permit seeds to dry and the wind to enter to the right a fruit later in the season Two views of a flat seed at the top each one slowly splits into three parts which gradually separate from each other. Why do they not burst open all of a sudden like pea pods and shoot the seeds all about and have the job done with Or why does not the pod burst open at the lower end first instead of the upper?  Observe that the three opening cells are lashed together loosely with a latticework No slight breeze can dislodge the seeds but just see how they behave in a gale The elastic stems are swayed back and against each other and some of the upper seeds tossed out by the wind that passes through the and at such times are often carried to some The seeds at the top having escaped the dry pods down farther and still farther and open still wider the bottom is reached As
  the seeds are not all away the first or even the second time and as breezes may come from different directions it is possible for the lily to scatter its seeds in all The seeds of the lily are flat very thin and rather light not designed to be shot out like bullets but to be carried a little way by the wind the pods are erect and open at the top that the seeds need not escape when there is no wind or unless some animal gives the stem a strong shake The latticework was made for a purpose and the gradual opening of the pods prevents the supply from all going in one direction or in one day for a better day may arrive "

I'm fascinated by this latticework and I took this picture of a dry Lilium washingtonianum,  <http://flic.kr/p/g6ikfp/>.

But how do lilies, and also Erythronium appear as pioneers in cutbanks or recently disturbed ground. Surely as discussed in this earlier post established bulbs are released into blooming condition by over-story removal.I have not found any mention in literature yet of a seed movement mechanism in lily, Erythronium yet but I think the flat shape adheres to passing wet animals on feet and fur, feathers. 
   
Clips from original reference

 http://books.google.com/books/…

http://books.google.com/books/…

Richard Haard, Propagation Manager
Fourth Corner Nurseries
Bellingham, Wa.

Native Plants Forever






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