[Terrapreta] growth

[Richard Haard]

Some results from the 28 - 17 foot planting block experiment with  
charcoal, compost, fertilizer and permutations. at Fourth Corner  
Nurseries with swiss chard, a native aster and a woody shrub,  
Lonicera involucrata.

Spent a few hours at the research plots today. Picked swiss chard and  
squash for dinner and farm crew.

Above ground results so far (July 29) are as expected. Best is  
compost plus fertilizer with or without charcoal, next fertilizer  
with or without charcoal, next compost with or without charcoal and  
last control with or without charcoal. The only measurable  
differences in these sets is with the swiss chard.

I decided to omit the urea treatment as soil analysis showed adequate  
nitrogen levels in both compost and  fertilizer treatment sets.  
Growth is very rapid now and I plan next week to harvest and blanch  
November.

A first look at the soil analysis on samples collected end of June .  
Next samples will be taken for soil testing in November just before  
harvest. This set of samples is essentially at the beginning of the  
experiment about 6 weeks after plots were set up. 23 months to go  
before the experiment is finished.

Total = 24 plots All OM= 5.04 (.72)  All N=14.7 (9.4)

Total =  2 plots control OM = 4.6 (1.7)  N= 2.5 (.71)
Total =  6 plots charcoal and control OM = 4.73 (.79)  N=5 (5.1)
Total =  4 plots charcoal  OM = 4.8 (.27)  N= 6.25 (6.1)


Total =   2 plots compost OM=5  (.57) N=10 (2.8)
Total =   4 plots compost and charcoal OM=5.78  (.60) N=12.75 (3.4)
Total =   4 plots compost and fertilizer and charcoal OM=5.5 (.34)  
N=19.25 (7.3)
Total =   2 plots compost and fertilizer OM=5  (.42) N=34 (2.8)

Total =  2 plots fertilizer OM= 4.65 (.77) N=20 (11.3)
Total =  4 plots fertilizer and charcoal OM= 4.53 (.64)  N=16.75 (2.6)

Key
         OM= organic matter %
         N= nitrate ppm
         bracketed (__) = standard deviation (a statistical measure  
of variation between the set of samples)

Considerable variation is noted in soil analysis numbers at either  
ends of test row hence an explanation of large variability seen in  
some sets.

It is interesting to see the effect of compost ,fertilizer and  
charcoal additions on soil om and nitrate. Have not looked at this  
set of data yet on some of the other items of interest as CEC, and %  
base saturation.  There is essentially no difference between the  
treatments  in pH and buffer pH.