Spring is finally here, at least the redwing blackbirds think so, and as I look out across the meadows I can enjoy a moment of hopefulness. Things are beginning to turn green. A gentle and easy green, before the rank growth of May dashes any hope of keeping up with Mother Nature flexing her muscles.
The fields I would prefer to be grass show themselves to be once again full of, yes, that dreaded four-letter species Ñ the weed. My beautiful agricultural monoculture is again undone by biodiversity. If I were really cropping, I would rotate and fallow, breaking the weed cycle (with the exception of the occasional volunteer). But we are growing hay. Plow and re-seed every year? Some people do it, but the costs of equipment, fuel, and seed, as well as the environmental consequences, are beyond me.
Several years ago, as we took steps to recover from poor corn management on our fields, we placed some of the acreage into a wildlife conservation program. The conservation easement gave us some tax money and we were allowed a maintenance cut after the songbird breeding and nesting was over in August.
The "crop" was baled or composted, some sold and some spread, providing a little more cashflow and a big benefit to the burned out soil base.
After a couple of years of cutting and handling the bales of weed, I began to notice differences. The cut smelled different, the bales felt different, both from year to year and spot to spot in the fields. What was going on? My concerns led me to the books. Species identification, soil types, soil layers, soil tests, mineral and organic content, pH and NPK, oh my!
Anyhow, believe it or not, there is a master plan for all this. The dandelions and broadleaf led to sorrel, mustard, goldenrod, ragweed. These weeds all were doing a slightly different job in different places. They thrive in different soil types with different chemistries. They root to different soil depths to get what they need, bringing it to the surface. Weeds are mother natures? subsoilers. (Have you ever really found the bottom of a dandelion or thistle taproot?)
As the soil conditions improve nearer to the surface, the turf-builders begin to come in. Foxtail, crab and quackgrass, clover and vetch, binding the infant topsoil and organic matter, mining atmospherically, fixing nitrogen and carbon.
Compost tests also showed changes in mineral contents as the soils improved and "weeds" changed. And now over the past year, the real grasses are coming in. Timothy, redtop, brome, orchard, all in a healthy mix with the weeds. Our horses will now eat this "hay." They're not as fussy as some of their uptown cousins, and they actually prefer it over some "cultured" hays we have experimented with.
Think of it as a mixed salad; it all tastes a little different. I can tell you a sweet stem of timothy from a dandelion green with my eyes closed.
There are additional benefits to this meadow culture, including this important one: The carbon cycle is operating at peak efficiency. Tillage is disruptive in two ways: It compacts soil, reducing its ability to store nutrients, and it introduces oxygen, which accelerates decomposition in the soil and speeds carbon releases. Some studies are showing that aggressive tillage can actually have a negative impact on carbon banking.
I have more to say on this subject but I'm out of space for now, so until the next time, I'm hoping you'll think about and approach all those nasty little weeds differently.
Don Wilson is chairman of the board of the Bennington County Conservation District. The Web site is at www.bccdvt.org.
This column appeared in the Bennington Banner in April 2009, as one of the BCCD's Conservation Currents pieces, a bi-weekly feature written by BCCD board and staff members since August 2006.