[APWG] Purple in cheatgrass

[craig at astreet.com]

Dear Shawn and All,
Hello to our weed friends from down under.
 Sorry to hear that you have cheatgrass in Australia.
In
replanting a square miles of cheatgrass land in 1994-5 in our Great Basin,
that you can see at http://www.ecoseeds.com/greatbasin.html, we found that
the cheatgrass always indicated phosphorus poor solis.  
So
poor in fact, that without fertilizer, we could got get the local native
seeds to survive as seedlings, like you can see at
http://www.ecoseeds.com/good.example.
>From looking at photo
vegetation megatransects of Australia, that you can see at
http://www.ecoseeds.com/australia.megatransect.html, your land is in the
same  vulnerable condition as a lot of our arid lands are.  In
that the local native grass cover has been grazed away, leaving scattered
shrubs, like you can see at the photo coordinates of 24S-139E, with lots
of bare areas for the cheatgrass to colonize.
We invented a rule of
thumb for cheatgrass--Cheatgrass is a default-weed, only growing where the
local native grasses have become spatially extinct, or where soil
nutrients have dropped below the threshold required b y the local native
seedlings to properly survive.
We found that for each species of
native grass that we replanted on the site, each had a different range of
soil nutrient thresholds that they required for seedling survival.
 Poas and Sitanion (now Elymus) had the lowest requirement, and Great
Basin wild rye (another Elymus)  had the highest, and this was all
determined by doing soil tests for N-P-K and soil carbon
content.
Current images of my Palo Alto California grassland plots,
that are still 99.999% weed-free as on Monday, can be seen at
http://www.ecoseeds.com/arastradero.html.  A big contrast to the land
just outside of the test plot, the thistle plants are 3 per sq. inch, and
the exotic grasses 8 per sq. inch, which translates to 18 million and 50
million weed seedlings per acre.  I hope this encourages others to
try native straw mulch elsewhere on the planet.
Sincerely,
 Craig Dremann (650)
325-7333
 
 
 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.plantconservation.org/pipermail/apwg_lists.plantconservation.org/attachments/20130117/17603662/attachment.html>