Sludge Watch ==> WERF Summit - California - Documented crop damage from sludge

[maureen.reilly at sympatico.ca]

WERF SUMMIT - CALIFORNIA KERN COUNTY CROP DAMAGE - PROBLEMS COTTON ANAEROBIC 
SLUDGE BIOSOLIDS


http://www.werf.org/pdf/03HHE1.pdf

Page "140 of 187" - "As a UC farm advisor in Kern County, CA responsible for 
irrigation and soil management, I have worked with land appliers and farmers 
using biosolids for the last 10 years.   My own field trials have shown 
widely varying nitrogen mineralization from 10 - 71% one season.    Other 
field observations include occasional crop failures as well as some fields 
that have shown significant improvement and reclamation benefit from 
biosolids applications.

Field level management, application rates and subsequent crop management are 
often less than precise.     Other farmers, water managers, and location 
regulators are concerned about leaching of toxicants and pathogens and 
potential adverse publicity impacting crop value/sales, the list below 
suggests some production-level tools and research that would help answer 
some of these questions."

PAGE "141 of 187"  "4)  Determination of plant toxicity 
mechanisms/correlation with form of biosolids:   Researchers have noticed 
occasional adverse crop damage across the US.   Some of these incidents have 
been linked to excess salinity and/or ammonium toxicity due to over 
application.   Others, specifically cotton in Kern Country, have suffered 
drastic stand losses or the loss of lower leaves and fruit later in the 
season with severe injury to the upper leaves.   Composite field soil and 
plant analysis indicated very acceptable levels for all salts/nutrients -- 
indicating the problem lies elsewhere.   This problem has only been seen 
following the application of anaerobic biosolids."