Hi Jeff,
I know it works to improve soil for the purpose of agriculture.
For one example: I am working on one of the Atterburg Limits test for
Shrinkage. It goes like this:
I have a row of shallow cups ~ 1.5" diameter and 0.35" deep. (freeze
plugs from engine blocks) In the far left is a clay soil that has a lot
of swell/shrink properties. On the far right I have biochar with no
swell/shrink properties. The cups between are increasing char content
from left to right. At some point I should see a mix clay/char with
acceptable reduced shrinkage. To reduce cracks formed in the soil thats
breaks apart roots and channels water around the root system one would
need to add that amount of that biochar to that soil.
To show the benefit based on a plant growth study (like what you are
doing) you would need to farm the soil in a way that would form cracks,
tear apart roots and channels water so that these are the limiting
factors to plant growth. Only then will you see increased production and
difference in plant health, water savings etc.
So is it a wash? waste of time? waste of money?
For the above example it depends if the problem can be solved by a other
cheaper means like a different watering system. A drip system with added
gypsum keeps the soil always swelled and not permitted to shrink/crack
works well if done right. How much char is needed? I believe it needs a
critical amount to make a difference or nothing happens. And then you
see no difference in plant growth studies if the improved soil property
is not made the limiting factor. That may only occur during a dry spell,
when a farmer forgets to water or blocked water lines etc.
So for this one example one may need to build up biochar in the soil
over the years and only see a benefit once every five years. Benefits
may be in water and fertilizing savings and not in crop response. The
question is not can it improve the soil, but is it worth it and how do
you measure savings and benefit.
Thats the way I look at it.
Regards
Frank
Jeff Davis wrote:
Dear All,
My experience is that adding charcoal to the soil is a wash. Sometimes the
plants did better than the control, sometimes they did the same and
sometimes worse. In other words I have found Biochar to be a waste of time
and resources. Furthermore the increase in CO2 in our atmosphere is not
caused by the lack of biochar in the soil, it's because of our addiction
to oil and coal (assuming man made global warming).
After trying many growing schemes I have found that plants flourish in a
humus rich soil. Humus is not compost but may start out as compost. It is
a sticky form of carbon (plus) that can last in the soil for a long time.
Furthermore plants and soil/humus has evolved together for thousands of
years if not millions. Nature already has a design in place.
Jeff
_______________________________________________
Stoves mailing list
[email protected]
http://listserv.repp.org/mailman/listinfo/stoves_listserv.repp.org
http://stoves.bioenergylists.org
http://info.bioenergylists.org
UNSUBSCRIBE HERE;
http://listserv.repp.org/mailman/listinfo/stoves_listserv.repp.org
--
Frank Shields
Soil Control Lab
42 Hangar way
Watsonville, CA 95076
(831) 724-5422 tel
(831) 724-3188 fax
[email protected]
www.compostlab.com
_______________________________________________
Stoves mailing list
[email protected]
http://listserv.repp.org/mailman/listinfo/stoves_listserv.repp.org
http://stoves.bioenergylists.org
http://info.bioenergylists.org
UNSUBSCRIBE HERE;
http://listserv.repp.org/mailman/listinfo/stoves_listserv.repp.org
