Re: fungal vs bacterial/ till no? No till?

From: Elaine Ingham (Soilfoodweb@AOL.COM)
Date: Sun Apr 20 2003 - 17:15:16 EDT


Hi Gil -

I agree that often times the grower knows enough about their land and past practices that they should have a really good idea of what is going on biologically in their soil.

But sometimes, even though things should be going right, they aren't. Take the front lawn at SFI. We have been using compost tea, a few organic additives like kelp, corn gluten, and the occasional product that people want tested, and we are having a weed problem. Head-scratching. But then we noticed that the soil is extremely compacted, as shown by the imbalance in active to total bacteria, no beneficial fungi present, and extremely high ciliate numbers.

The people who own the protperty have been over-watering. It's water-logged the soil. So, we have to get them to turn the water off, because healthy soil requires 50% less water than poor-structure soil. Especially in western Oregon, over-watering can be a real problem.

But, what do you do to fix this, now that we've figured out what the problem is? First, reduce water by 50%. Then get air back into the soil.

Aeration cores are the best bet. Fill the holes with fungal-dominated aerobic compost, with VAM spores, because we've lost the beneficial fungi completely in that soil.

It was the soil biology analysis that let us know exactly what was wrong, and how to fix it.

Often turf people just apply humic acids in a similar condition, and hope that was all that was needed. But then a month later, you know it wasnt' adequate to fix the problem. The grass is in serious trouble.

If it is economically worth while, running a check and knowing what needs to be done solves the problem before the plants die.

It always comes down to a question of cost - benefit ratio. Do you spend the money to do the testing BEFORE the plant response lets you know something is wrong?

Depends on how much money will be made on that crop. If the crop isn't that big a deal, and you can afford to lose productivity, or maybe lose the crop all together, then letting the plant tell you something is wrong is ok.

But if the loss of part or all of the crop would be economically devasting, then doing the soil biology, and chemistry, analysis is worthwhile.

If you can afford the consequence of guesswork, then guess. If the potential improvement in production is more than the cost of the testing, then it makes sense to test, and then correct the problem.

If you know your land, and the impact that the things you do to it have on the biology, then you aren't doing guesswork.

What I'd really like to do is have people add manures, different kinds of compost, different products, and then test to see what the affect is on the biology. Then we'd KNOW what adding these materials actually is. In the future we'd just need to assess the quality of the compost, or manure, and we'd know what effect the additions have on the soil. Less and less testing would be required with time, and we'd have a better idea what to do in different situations to really fix a soil to grow what you want it to grow. So, here's hoping for that kind of knowledge base!

I'd love to work with you to train people in the Phillipiines to do the kind of testing that we do.

Elaine Ingham
President, Soil Foodweb Inc.
SFI Corvallis, OR
SFI Port Jefferson, NY
SFI Lismore, NSW, Australia
SFI Hilversum, The Netherlands
SFI Cambridge, New Zealand
www.soilfoodweb.com




This archive was generated by hypermail 2.1.5 : Mon Apr 21 2003 - 15:26:37 EDT