[APWG] Native plant herbicides--just set up small scale test plots?

[Craig Dremann - Redwood City Seed Company]

Dear Wayne and All,

Thanks for your email.

You never ever need to know exactly what natural herbicide chemicals are
working, to kill the weeds.  Just use the native plants against the weeds
in small scale trials, like my Nassella straw that I just put down two
inches thick at Arastradero a week ago.  Between now and when nights get
cold is the best time to set up your test plots, using different plant
materials vs. the weeds. .

All you have to do is measure---how much allelopathic material did you use
to suppress the weeds?  In my test plot, it will be two inches worth of
Nassella pulchra straw.

I usually measure the material in inches thick and also in ounces per
square foot.   My two inches thick equals 1/3 pound per square foot.  By
measuring weight per area, you can then calculate how much you need for a
large project, like to do the whole 70 acres at Arastradero.

The test plots do not need to be very large--I use as small as one square
foot per treatment on the ground, or for ex-situ test plots in pots, I go
down to 3 inch square pots.  I saw a presentation by Caltrans (our State
DOT) last year, where they showed a Powerpoint photo of the 3 inch square
pots they use as mini-test plots too.

By the way, the managers of Arastradero were able to get a lot of wood
chips from a tree trimming company, and a year ago, they planted beautiful
native Nassella prairies using locally collected seeds, near the buildings
to the right of the parking lot, and above the parking lot.

By using the wood chips to their advantage, the allelochemicals in the
chopped up tree branches suppressed all of the weed grass seedlings, that
would have germinated and interfered with the Nassella planting.

The weed grass weeds here in California are fierce, germinating at the
rate of up to 40 seedlings per square inch, so if you do not discover the
magic of native plant allelopathy pretty quickly, your weeding efforts or
native plantings attempts,  usually have major, major problems.

So get out and spread some native materials in weed areas, and within six
months, you should see some results, if you use tree leaves, shredded tree
trimmers  branches, dried plant stems, or native grass hay.   I will look
forward to whatever anyone discovers in spring.

WEED MANAGEMENT/RESTORATION=Carbon credits?  To bring up another topic, I
think we need to bring all of our large scale weed management and
ecological restoration, into the new carbon economy.  When we are planting
out the native plants whose roots could sequester a certain amount of
carbon per acre, perhaps there will be a market for that sequestered
carbon sometime in the near future?

Sincerely,  Craig Dremann (650) 325-7333