[Terrapreta] Numerical data

[Richard Haard]

This is addendum to my earlier report of

Charcoal in agriculture: Experimental research at Fourth Corner  
Nurseries
Richard Haard, Fourth Corner Nurseries, Bellingham, Washington,  
January 3, 2008

posted recently at
http://terrapreta.bioenergylists.org/haard4cncharcoalreportjan07

I have been looking at the data sets of the soil analysis we conducted  
on the plots on June 25, 2007 and October 30, 2007. The first soil  
samples were taken about a month after project setup and planting and  
the last was at the end of the growing season. I sampled with a hand  
held soil coring device, and took samples uniformly in each 17 foot  
long test bed. They were dried and screened to remove lumps and pieces  
of wood/charcoal etc.

We sent the samples to the soil lab and had a standard soil test run  
with for organic matter, major, minor and trace elements, Cation  
exchange capacity (CEC) and associated base exchange percentages for  
K, Mg and Ca.

There were a few anomolies in the data set that should not be  
surprising as there is no reason to expect a 500 long by 4 foot wide  
section of a farm field be uniform in analysis. In addition, without  
doubt there is sampling error. One of the control samples read  
abnormally high the first reading and then fell into the same pattern  
as the other control plot. This is the reason why control ranking is  
skewed in the data set.  Otherwise the data is remarkably consistent  
and I feel I have learned something about using compost and charcoal.

I obtained a program to plot on an x,y and z axis any three items for  
each treatment plot. I chose to look at Organic matter, CEC and  
Phosphorus. It gave me a cute 3D image that ranked the data sets on  
all three parameters at once.

Item by item there were changes from June to October. In all of the  
plots soil Phosphorus ranged from 5 to 8 (PPM) in the spring and from  
7 to 12 in the fall. Organic matter also increased from 3.4 to 6.5  
(% ) spring and 4.1 to 7.5 in fall. the CEC also changed  10.8 to 15.3  
(MEQ/100g), spring and 9.3 to 13 in fall.

The rankings shown by this  program indicate synergistic effect of  
compost and charcoal. Charcoal1 tended to score higher as is expected  
since it is a fine powder.

(Cm= compost, F=Fertilizer,C1= John's Charcoal, C2=Larry's Charcoal,C=  
Control)

If we take all 4 readings (duplicate sets taken twice) as averages,  
the 3 way comparison, (of OM, P and CEC) , sorted things out this way

Cm+C1 > Cm+F+C1 > Cm+C2 > Cm+F+C2 > C > Cm+F > F+C1 > Cm > C1 > F > C2  
 > F+C2

Relative rankings 1 to 24 were averaged showing this spread

22, 22,16.5,15.5,13.5,12.5,12,11.25,10.5,8.5,7,6

This indicates to me there is a synergism between the compost and  
charcoal.

I'm looking forward to more data next season from the same plots

Best Wishes

Rich Haard, Propagation Manager, Fourth Corner Nurseries, Bellingham,  
Washington