Winterizing Your Vineyard

By Charles Schembre, Vineyard Conservation Coordinator

After conducting winterization/erosion control inspections on over 150 vineyard properties throughout the County, we want to take a moment to share our observations.

Ground cover is one of the most critical erosion control BMP’s.

Rains came early and steady this fall, promoting ideal conditions for cover crop seed germination and natural revegetation of ground cover. We have seen very few large erosion issues in Napa County this year, most likely as a result of excellent ground cover. A few vineyards, most of which were developed this year, experienced erosional issues from the first couple of medium size storm events because there has not been enough time for the soil to re-stabilize.

Straw wattles are often installed poorly.

Straw wattles will not function to mitigate soil erosion and concentrated flow if they are installed improperly. We recommend that vineyard staff are educated every year about how to properly key in straw wattles. The method below takes time, but if a straw wattle is not installed property it is useless.

How to property install a straw wattle

Install the wattle on contour so that it is near dead level. You can simply use a hand level in the field to achieve this.
Dig small trenches across the slope on contour. The trench should be deep enough to accommodate half the thickness of the roll, roughly 6 inches deep.
It is critical that the rolls are installed perpendicular to water flow.
Lay the roll along the trenches fitting it snugly against the soil, making sure no caps exist between the soil and the wattle
Drive 1×2 or 2×2 wooden stakes through the center of the wattles, and also the alternate stake method, every 4 feet.
Build up a small berm and tamper it down on the upstream (upslope) side of the wattle.

Click HERE for instruction graphic