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Re: Dueling substrates

> From: Stephen Pushak <teban at powersonic_bc.ca>
> George is not a spokesman for my views ... My opinion is
> that he is taking perceived criticism of laterite far too personally. 

> From: "Dennis J. Harney" <harneyd1 at muohio_edu>
> I believe you fellas are speaking of two different things here:  optimal
> growth and fertility ... Definitely an
> interesting discussion (probably for another forum).

> From: Pete and Kellie Schmidt <petes at nas_com>
> Subject: Dupla spokesperson / Kitty litter / Laterite / Soils etc
> Come on George, you are making this not so much fun.  

I apologize if I made this discussion too interesting.  Jim Kelly posted an 
excellent "low cost substrate" article many years ago which was the first time I 
had seen a table of CECs for various materials. Laterite was last on the list 
with a value of "4" and the implciation, if my memory serves, was that one would 
want a higher value in the substrate. Jim suggested adding vermiculite (CEC=150) 
at that time. 

I challenged the assertion that the CEC of laterite was too low then and I still 
do when it comes up. I guess I should stop beating a dead horse.  No one seems 
to know the answer and fewer yet seem to care. 

OK, just one more whack. Perhaps someone who feels like doing a wee bit of 
research could consider if the CEC value stated for "laterite" (4) is a true 
value, representative of all laterites, or if it was an average, much like the 
average content of iron in soil has a value but was shown to be a relatively 
useless measure since the range of iron content in soil was quite large.  

Cheers until Jan. 5,