A rain at harvest can be expensive – damage to the crop reduces the quality and premiums received from the huller, increase harvest costs reduce profit, and the use of forced air driers are costly. With rain imminent, it is important to keep in mind that practices should be employed to speed the drying of crop, whether it is in the tree or on the ground. The following guidelines may provide some help during a rain event during harvest.
If rain is forecasted, do not shake trees as almonds will dry more quickly when hanging on the tree due to increased air circulation.
If nuts are already on the ground, blow them away from trees but not into windrows or piles. Doing this will help prevent the nuts from sticking in the mud within the tree row strip. Once the nuts are stuck in the mud, it is difficult to move them away from the trees.
Once the rain event has completed, rake the almonds frequently, turning them until they are thoroughly dry.
If they are already windrowed, run them through a pickup machine and let the nuts fall out of the back. This will help turn the windrow nuts, increasing air contact, and will help remove wet debris from the pile.
A table developed by Larry Reinhart (North State Hulling Company) is provided below to serve as a further guide – especially if showers or high humidity persists.
Information sourced from Chapter 35 of the Almond Production Manual:
Connell, J.H., G.S. Sibbett, J.M. Labavitch, and M.W. Freeman. 1996. Chapter 35: Preparing for Harvest. Almond Production Manual. University of California, Division of Agriculture and Natural Resources. Publication 3364. Oakland, CA.