Farm Calls: Vineyards, Helicopters, Frost Protection ...and Right-to-Farm

This week brings a call from a wine grape grower asking if the use of helicopters is among the accepted standard operating procedures in fruit growing regions during Inversion Layer Freezes.

There are two kinds of freezes affecting fruit crops:

Figure courtesy NCSU
Cooperative Extension

• Advection Freeze occurs when a very dry cold air mass moves into a region with strong winds
• Radiation Freeze, aka Inversion Layer Freeze, which occurs with a very dry local air mass, little or no wind, and a clear sky.

Helicopters have documented efficacy to reduce losses only against Inversion Layer Freezes and are considered part of legal Right-to-Farm protected standard operating practices in the US.

Other methods of protection against freeze include wind turbine machines, heaters and open burning (which requires NJDEP Exemption, as was granted in NJ 2012), water sprinklers, and cultural practices, e.g., moist bare soil in a vineyard makes vines less prone to freezing injury than dry soil with vegetation under the vines.