From bluestem@webserf.net Sun Oct 10 18:08:39 1999 Date: Sun, 10 Oct 1999 19:53:12 +0100 From: Bluestem Associates To: "sanet-mg@ces.ncsu.edu" Subject: Re: Organic and nutrition (Nigh) On Sat, 09 Oct 1999 19:11:59 -0500, Ronald Nigh wrote: >But how do you explain this situation? It is virtually impossible to grow >organic vegetables, grains or fruits (not to mention animals) without >adequate mineral and micronutrient management You can grow all kinds of stuff in all kinds of goofy soils without paying attention to anything. I've worked with some soils in the Andes that you wouldn't expect to grow much of anything, and they didn't. But they *did* grow something. Not a lot of it, and probably not of very good quality (I didn't check), but it did grow stuff. Similarly, here, people can harvest 20 bu/ac of crummy soybeans and feel they're doing okay because they get $14 a bushel for them. This past summer in my inspection work I logged over one-quarter million bushels of organic soybeans in storage because they weren't of buyer-acceptable quality. >Yesterday you criticized organic farmers for not doing soil tests to >determine mineral status. Conventional soil tests don't give us much >information on mineral status (o its nice ot know pH and OM). P soil tests >are very misleading--we have lots of P in some soils here but the plants >can be showing clear P deficiency. We have found trace analysis of seeds or >plant tissue to be more indicative of what is going on. But these are >expensive and so we try to go more on what the state of the plants and the >kinds of 'weeds', insects, fungi, algas etc. we find can tell us. I would >rather have a test of biological activity of the kind Elaine Ingham offers >than a mineral test of the soil. SFI's testing (Elaine Ingham, etc) does not yet have any predictive power for yield, or even soil health. We sent her lab a series of paired organic & conventional samples from neighboring farms using roughly the same rotation. SFI was unable to come up with any significant differences. The only pattern that possibly emerged was that heavy duty chemical farms had a "better" fungal ratio. Go figure. SFI are completely unable to demonstrate an correlation between their numbers and yield, so I tell farmers to save their money. Nice idea, brought to market a few years too soon. >What tests would you recommend? In general, what would you recommend as the >basics of organic mineral nutrition program for grains (corn)? for fruits? I use Midwest Labs in Omaha. Their consistency with split samples is excellent, and their interlab agreement (same test basis) is also good. Their overall CEC numbers tend to be low (and have been that way for 20 years) but it's a function of the way they calculate that value. Very complete test for $22. To Unsubscribe: Email majordomo@ces.ncsu.edu with the command "unsubscribe sanet-mg". If you receive the digest format, use the command "unsubscribe sanet-mg-digest". To Subscribe to Digest: Email majordomo@ces.ncsu.edu with the command "subscribe sanet-mg-digest". All messages to sanet-mg are archived at: http://www.sare.org/san/htdocs/hypermail