I. brevicaulis won't set seed

I'm cross-posting this message, so some of you might see it twice.  But I 
have a perplexing problem that I think both of these Yahoogroups can help 
me with.

A local nursery specializes in distributing seed of locally collected & 
propagated wild flowers.  They have two enormous patches of Iris 
brevicaulis that must contain upwards of 1,000+ plants.  This spring the 
bloom was glorious, but by September there was only ONE seed pod to be found.

Now the wild population still exists, but is substantially smaller than 
what the nursery cultivates.  The wild population set abundant seed!  So 
certainly the problem the nursery faces couldn't be related to rain fall, 
or weather, or temperatures.

Do you have any idea what could cause such a pathetic result?  Perhaps 
overcrowding?  (They are indeed quite overcrowded!  If you try digging up a 
single rhizome you'll get a whole mat of them crisscrossed together 2 or 3 
layers deep.)  Herbicides?  They do not fertilize, so it couldn't be 
overfertilization.  Could it be soil type?  I don't know.  I am totally 
baffled.  I can't comprehend how so many hundreds (thousands?) of plants 
could manage to only produce ONE seed pod!  Do any critters specialize in 
eating iris pods???  mice?  deer?  bugs?  beetles?

They get full sun at the nursery.  They are irrigated weekly.  Could 
chemicals in the water be to blame?  A soil deficiency?  These plants 
increase vegetatively without any problem, and show no sign of stress, 
other than the occasional bout of rust.  They seem perfectly healthy I just 
can't figure why they refuse to go to seed.  Neither can the nursery staff.

Dennis in Cincinnati

PS:  I have an article in the upcoming SIGNA issue about these I. brevicaulis.



------------------------ Yahoo! Groups Sponsor --------------------~--> 
$9.95 domain names from Yahoo!. Register anything.
http://us.click.yahoo.com/J8kdrA/y20IAA/yQLSAA/2gGylB/TM
--------------------------------------------------------------------~-> 

 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/iris-species/

<*> To unsubscribe from this group, send an email to:
    iris-species-unsubscribe@yahoogroups.com

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index