[APWG] What caused surprise results in Poppy Project?--None of the guesses so far got it.

[craig at astreet.com]

Dear Robert and All,
Thanks for your guesses.  The two pots
were set touching each other, getting exactly the same amount of water,
heat, light, and the same number of seedlings popped up, but in one pot
they all died, and not from damping off or heat or lack of water or
overwatering.
It is something that is very, very rarely looked at
when sowing native seeds, and is also a major cause of weed infestations
here in the arid West, and perhaps also in the East.  We have
assumptions about native plants and weeds, those erroneous assumptions can
be proved completely wrong by doing some of these ex situ pot
tests.
I got the exact same results in 1993 with the Great Basin
soils with the ex situ flat tests that you can see at
http://www.ecoseeds.com/good.example.html that I used as one of my
exercises for my California DOT native plants for roadsides classes across
the State in 2000.  
Now these ex situ pot tests are a regular
part of the Caltrans roadside native plant revegetation
projects. 
Sincerely,  Craig Dremann (650)
325-7333
=========
> Pot studies are very useful for
determining the way things happen in pots.

> That information may or may not apply to the real world. I would not
bet

> the farm that what happens in pots will actually happen in the
field.

>

> Your question of why the seedlings all died is most likely answered
by the

> complex called "damping off". The only other reasons I can
think of might

> be not watering enough, in which case drought is the answer, heat
stress

> that cooked them, cold that froze them, or watering too much, in
which

> damping off is still the "actual" cause.

>

> If your previous pot studies have accurately predicted that way
things

> will happen in the field, good for you!

>

>

>
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