There Will Be a (Soil) Test

Well, I’ve gotten my wish, in a manner of speaking.  For the past two weeks, every Tuesday and Thursday night I go to “school”–in my case a Nutrient Management class put on by the Frederick Extension office.  Sitting under fluorescent lighting and listening to an instructor make hints that, “you might see this topic again on the test” is giving me major deja vu.  While the language and setting are reminiscent of high school, my classmates are anything but.  With the exception of three other women and a couple of young men, I sit in a classroom filled entirely with middle-aged men.  I think I’m the only person who gets a kick out of the mathematical gymnastics.

Maryland is very concerned about the impact of agricultural fertilizer on water quality in the Chesapeake, and so state law requires that all farmers grossing more than $2500 per year or raising more than 8000 pounds of livestock create and maintain and nutrient management plan.  I could hire a consultant to write my plan for me, but the idea of paying someone else to design my fertility systems seem ridiculous (and expensive).  Besides, Andrew and I got into this business because we believe that careful farming improves soil and water quality, so writing a plan seems like one way I can work toward that result.

I had hoped that the class would touch more upon the science of soil processes, the value of micronutrients, and the difference between various fertility sources.  Unfortunately, given the limited time, the bulk of the material emphasizes how not to run afoul of the regs and how to do calculations for appropriate application levels of the “agricultural big three:” Nitrogen, Potassium, and Phosphorus.  If you’re growing conventional corn, I’ve learned, you don’t loose much sleep over soil organic matter or a minor Molybednum deficiency.

Taking soil samples is a lot easier in a silty loam than in a gravelly silt loam (aka the chicken field)

Despite the conventional bent of this class, it has gotten me thinking about my systems and ways to improve on what we already do.  In particular, I’ve been thinking lately about Nitrogen.

Nitrogen is a ramblin’ element, forever transmuting in form and availability, and therefore a reading one day would not guarantee availability the next.  But Nitrogen is critically important for growing healthy crops; without it, my plants would be stunted, yellow, and unhealthy.  There is a balance to this, of course.  Too much nitrogen can lead to overlush plants that put on excess greenery at the expense of fruit.  But if you get the balance right, you get healthy plants, full heads, large fruit.

The reason I’ve been thinking about Nitrogen is that I fertilize my fields with aged manure and compost.  Manure and compost are fantastic sources of organic matter and contain a host of beneficial micronutrients, but if I applied manure at a rate to supply all of the nitrogen needs of my crop, I would be over-fertilizing with respect to phosphorus and potassium.  I don’t like solutions that create new problems.

Conventional fertilizer would be an easy answer (though arguably of those solutions-that-creates-new-problem).  Organic agriculture’s response would be to apply bloodmeal, as it contains 13% nitrogen compared to only 1% Phosphorus and .6% Potassium.  I’m not a fan of bloodmeal, however, as it is a waste product of the huge Confined Animal Feeding Operation (CAFO) slaughterhouses that raise beef on grain and antibiotics and hormones.  We compost the blood, offal, and feathers of our chickens, all of which have been raised on pasture without hormones or antibiotics (that’s going to be some awesome compost!), but not at a scale to fertilize my two acres of crops.

So I turn to my favorite farming book, Eliot Coleman’s New Organic Grower.  I read it for the first time the same winter in which I read The Omnivore’s Dilema, as I waited for spring and my first farm apprenticeship.  Both books fired my imagination with the promise of farming, and The New Organic Grower, at least, offers new inspiration whenever I turn to it.  I swear I could read it every year for the next ten and continue to glean new ideas.

On the question of Nitrogen, Eliot offers this advice: alfalfa meal.  It is a low test fertilizer (only providing 2.4% nitrogen, though no phosphorus and potassium), but one that is entirely plant derived.  I file it away to be another piece of our system, one more strategy to care for our land.

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