Welcome back to ‘The Happenings.’ The last time that I wrote to you all, I filled you in on the some of the issues we are addressing in the vineyard. We have been attempting to loosen the soil throughout our oldest vineyards and are currently employing multiple strategies.
One of the methods that we have chosen includes the planting of an intra-row cover crop. We have selected a plant within the Brassicaceae family of crops, and more specifically in the genus of Brassica. Diving further into the taxonomy, we have settled on a plant within the species Bassica napus. Some of you may know that this grouping of plants also includes turnips, mustard, kale, and rutabaga to name a few. So, how does this tie into our compaction issue? Well, the Brassica genus of plants typically grow a long central taproot (Figure 1.) This taproot should reach deeper into our soil and after the plant cycles has ended, the tap-root will decompose leaving a void. In theory, the plant acts as a natural aerator and with continuous use, we should be able to keep the soil more open than we have in the past.
This is not the only reason that we have selected this type of cover crop. This family of plants also works as a natural biofumigant. The plants produce organic compounds known as glucosinolates. When the plant is injured (chewed, broken, cut, etc), a breakdown process occurs. The glucosinolates combine with water and myrosinase within the plant’s cell wall. This process produces a compound called isothiocyanate. The isothiocyanate compound is the same compound that gives heat and bitterness to horseradish and other members of the Brassica genus. It is the plant’s natural defense against being consumed. By mowing the crop and incorporating it into the soil, it is our hope that the isothiocyanate will help suppress weed seed germination, reduce soil borne pathogens such as fungi and nematodes and play a role in our view of a positive soil ecology.
There is one more major advantage to these plants and it has to do with nitrogen fixing, but I’ll save that for another post when I’ll also discuss interrow cover crop cultivation and fostering. Okay all, I think that’s enough science for the day.
It is spring time, so go out and enjoy a nice glass of Rose. I know I will.
Director of Operations