Better Farming - October 2016

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50 Farm News First > Better Farming October 2016
CROPS:THELYNCHFILE
Side dressing fertilizer.
This variability brings to light
another issue. How come you get a
different analysis if you send the same
soil to two different labs? There are a
total of seven accredited labs in
Ontario, meaning they have passed
the test of being able to perform the
various extractions that the provin-
cial government recommends for On-
tario soils. However, when you send a
soil sample for analysis the labs may
not perform the analysis in the same
manner as they are accredited to do.
There are a lot of political reasons
for this divergence. In Ontario years
ago it was decided that the “scoop
size” used by most labs in the United
States was not representative for
Ontario soils. As a result, the accredit-
ed test is done with a larger scoop size
than some U.S. labs use. Also, the
amount of time that a soil sample is
shaken differs between labs. Obvious-
ly, if you use a larger scoop size and
shake the sample for a longer period
of time, the soil solution releases more
nutrients for extraction. So, if you
send the same sample to two different
labs you will get different results.
Does all of this give you less faith
in the soil analysis system? I hope not.
Sampling is still the only way to
know what is in your soil. However,
when you see changes in your soil test
McCormick_CC_Oct16.indd 2016-09-09 10:44 AM