Thanks for reading that...I know it's long and scientific, not exactly an easy read. And you are right about the paucity of information on practical application. There is another, much shorter, article by the same team which talks more practically about how to use the wood chips:
http://www.sbf.ulava...g_soils_98.html
Your skepticism is understandable, and certainly I don't expect any of the growers here to accept these findings at face value. The paper I linked to does seek to make relevant to the world at large the crucial link between hardwood forests and soil fertility, but it stops short of completely "generalizing the specific," as good science should...Certainly there is much more work to be done...
For me, personally, I took a circuitous route to this information, and how I got there doesn't really matter. I will try, however, to give you my view of it, as a Southern gardener growing in the exhausted soil of a broad alluvial valley:
In my area there are several large valleys that are and have been historically important agricultural basins—The two I know the best are the Ouachita River valley of NE Louisiana and the Red River valley of NW Louisiana. I mention the Ouachita valley because as a child I walked alone there in the only virgin hardwood forest I have ever known: pillar-straight oaks towering 80-100 feet over a pool-table-level floor, carpeted with a thick, aromatic layer of rotting leaves and branches. Twilight dimness in the middle of the day, almost perfect silence, but a sense of massive space, like a Gothic cathedral...
Okay, enough with the prose...
When the cotton gin was invented in the 1780s and King Cotton swept across the South in the 1820s and 1830s these forests were cut down wholesale as planters exploited the millennia-old rich soil. The resulting harvests were massive enough to build a regional economic empire which, for a time, supplied over a third of the world's cotton. After only a few years the earth was exhausted and the growers either moved on to other valleys, or began using manure or chemical fertilizers in an attempt to replenish the spent ground. How was this not slash-and-burn agriculture, albeit on a much larger scale? This is where we are today with farming. We are taught in school that alluvial valleys are fertile because of the river-borne sediments, but that is only part of the story.
The point Prof. Lemieux's paper does make, and well, I think, is that although the normal practice of amending soil with manure and fertilizer is effective on a temporary, superficial, basis, it neglects other crucial components of healthy soil. Soil lacking ramial hardwood, although capable of growing healthy plants, is far more likely to host problems that could easily be prevented. For example, in my area heirloom tomato plants grown in sand and manure, without hardwood chips, will always succumb to the Southern Root Knot Nematode. Gardeners around here are fond of saying "My tomato vines always burn up around the middle of July." What they don't know is that their plants can't get enough water because their roots are completely knotted up and impervious with the wormy pests. Breeders have given us nematode-resistant varieties of tomatoes and chiles, but that ignores the real problem.
So—practical application of this knowledge—I'm still real new at gardening, and certainly I'm a newbie on this board, but I have been using shredded hardwood in 3 different in-ground gardens since 2009, with good results. Whether I'm growing in sand, clay, or varying amounts of both, I mix in plenty of shredded hardwood, up to 50%, before I form up the rows. In clay I will use more to increase porosity and permeability. If it is new, uncultivated ground, I will use commercial gardening soil in a "pod" around each plant, because it takes at least one year for the shredded hardwood to begin producing all its wonderful chemical and biological agents. Also, and this is critical, raw hardwood sucks a huge amount of nitrogen from the soil as it decomposes. In the beginning I lost many plants to "nitrogen starvation." So now in the first year I amend heavily with Osmocote 14-14-14 pellets. Finally, I "coat" the rows with a thick (3-4 inches) layer of straight shredded hardwood, forming channels along the the tops to facilitate uniform water distribution.
I hope I wasn't too windy, but I feel strongly that this information needs to be shared with anyone and everyone who grows anything at all, but especially those who grow food. Here are a couple of photos of my 2011 garden: