From Gene Logsdon
The photo of stunted corn (above) tells why grain farmers don’t like trees in their fence rows. Don’t like fence rows at all, in fact. The trees suck the moisture away from crops, as you can see.
But what’s going on here? The corn in the other photo, just across the fence, growing the same distance from the same trees, is tall and healthy. Why aren’t the trees robbing moisture from this corn?
I can’t recall any time when two pictures tell a better story of what’s happening in farming. I took both photos on July 15, as I write this. I wish I could have gotten into a helicopter above the tree line and shot the picture to get both corn fields in the same photo so readers would know for sure this is a true story.
The field with stunted corn next to the trees has been farmed with chemical fertilizers, herbicides, and modern tillage equipment for many years. It has been cash-cropped to corn and soybeans following each other most of that time, with an occasional crop of wheat in the rotation.
The field with vigorous, healthy corn next to the trees is mine. The rotation here has been five years of pasture and one year of corn for the past eighteen years I have owned the land. I put no fertilizer on the corn at all, except for the green manure from plowing under the sod, and the manure droppings put on it by the sheep. I weeded it mechanically three times.
Both fields were planted about the same time. The row of trees runs north and south, so both fields get the same amount of sunlight. My corn is an open-pollinated variety; the cash crop corn is a modern hybrid. The soil type is the same. My plant population is about 20,000 per acre; the hybrid corn somewhat thicker— I’d judge about 28,000 plants per acre. My corn rows are 38 inches wide; the hybrid corn rows 30. Several rows away from the trees, the chemical corn matches mine in height and vigor, so it seems a logical deduction to say that the trees are robbing the corn of moisture, especially since rainfall has been only moderate so far this year.
But that is not the whole story. At one point in the chemical corn field, beyond where I took the photo, a sod waterway formerly ran from the tree line down a slight slope out into the field to prevent a gully from forming there. The waterway had been in place for years but this time around, the farmer cultivated and planted right through it. The corn in what had been the grass waterway is tall and healthy right up to the trees.
Obviously, moisture, or lack thereof, is only a contributing factor. The real reason for the stunted corn is reduced levels of organic matter in the soil following years of annual cultivation with subsequent compaction and erosion. In the other field, in pasture four years out of five at least, nature could keep organic matter stable or actually increase it over time. An adequate amount of organic matter evidently acts as a reservoir of moisture sufficient for both the fence row trees and the corn next to them. Anybody got any other explanations?
It is logical, it seems to me, to conclude that adequate organic matter in the soil can produce a good crop even if rainfall is below the requirements of modern cash grain farming. Or to put that another way, how much of the blame for lower yields because of “less than optimum conditions” as the experts say, should really be placed on low organic matter content, not adverse weather?
Then there is the other question. If my organic corn grows as well as the chemical corn right beside it when both get sufficient moisture, is not that free organic matter worth at least as much as the $150 or more of fertilizer per acre that is applied to the chemical corn every year?