Hello Tim,
Yes, I think that is quite correct about nitrogen testing being quite
variable. It seems to be a snapshot of what is available. For this
reason, Logan does not report nitrogen levels with their Basic test
results, which I think is to their credit.
There is a way to calculate estimated nitrogen release, if you know the
organic matter percent of your soil, which Logan does report. In
general if it is 5% or higher, you likely will not need to add
nitrogen. Mine is about 2%. Until I started adding 50# sacks of
soymeal, now feather meal, the garden never produced like I wanted it
to. It is extremely difficult to get those results by adding manure
and/or compost. For some reason, the percent nitrogen of the amendment
plays a big role in it's effectiveness. Likely this is because it takes
some nitrogen just to decompose the carbon in the amendment itself.
Balancing all the cations is important, not just having enough
nitrogen. Balancing the anions is also important, though less understood.
Albrect's work was based on Mehlich 3 soil testing, so it is easier to
use results from a lab like Logan, which does Mehlich 3 testing.
I don't actually use Logan for the recommendations part of the process.
I like Michael Astera's book, The Ideal Soil. It lays out all the
arithmetic to balance the elements according to Albrecht.
All this mineralization, I think, is a worthy precursor to a highly
biologically active soil.
Erica
On 6/18/2011 5:50 PM, Tim Wilson wrote:
>
> I did spend some time today searching for any information indicating
> that organic (sequestered) nutrients contained in compost or soil can
> be revealed by typical laboratory testing,[not painstaking heating and
> weighing, etc. for each nutrient] including Mehlich III processes. I
> am willing to learn if I'm incorrect so if anyone has some citations,
> etc. please post them
>
> Following is a not bad read and an excerpt;
>
> http://www.farmwest.com/index.cfm?method=library.showPage&librarypageid=125
> <http://www.farmwest.com/index.cfm?method=library.showPage&librarypageid=125>
>
> "Nitrogen is present in the soil in a variety of forms that change
> from one to another (see the Nitrogen Cycle section). This has caused
> the limited use of soil N analyses throughout the world. Most of the N
> present in agricultural soils is in organic forms yet plants largely
> feed on inorganic N, particularly nitrate. Nitrate can be readily
> measured in soils, but the amount in the soil at any one time may not
> indicate how much is available to plants through the growing season
> because substantial amounts of inorganic N can be released from the
> organic forms (a process called mineralization). Unfortunately, the
> rate of release of inorganic N from the organic matter in the soil
> cannot be predicted by a chemical analysis at this time."
>
> Tim
>
> --- In compost_tea_at_yahoogroups.com
> <mailto:compost_tea%40yahoogroups.com>, "Tim Wilson" <thegoodjob_at_...>
> wrote:
> >
> > The only guts info I could find quickly was their newsletter with
> the articles about pH manipulation. Need to follow up before I can
> really say anything besides (??). In the farming community I lived in
> before I watched the locals chasing pH year after year following
> recommendations from the lab. It seemed to no avail, as we got equal
> to better yields completely ignoring pH and all manor of 'chemical
> soil tests' but (???)
> >
> > Tim
> >
> > --- In compost_tea_at_yahoogroups.com
> <mailto:compost_tea%40yahoogroups.com>, "steved3602002" <steved_at_> wrote:
> > >
> > > Logan Labs is an offshoot of Brookside Labs
> > > and both are based on the classic Albrecht
> > > soil test which is geared to mineral balance
> > > for soil structure and optimal microbial
> > > habitat, taking care of plant fertility,
> > > ultimately aiming for nutritionally balanced
> > > feeds and foods.
> > >
> > > Albrecht was a soil microbiologist, you know.
> > >
> > > Steve Diver
> > >
> >
>
>
Received on Sun Jun 19 2011 - 22:13:01 EDT