Dormancy

Carry out preventative practices for trunk diseases:

• Use delayed pruning or double pruning in February or later.
• Use applications of pruning-wound protectants after pruning and before rain in November through January.

In coastal areas, set out orange tortrix pheromone traps by December.

• Check traps twice weekly until a biofix date is established; thereafter, check traps weekly.
• Keep records (example monitoring form PDF).

If present, treat for Phomopsis cane and leaf spot before rainfall.

Sample for nematodes in January or February.

Carry out dormant-season sanitation activities.

• Destroy prunings of older infested wood to reduce pest sources.
• Remove dried grape clusters on vines and disc weeds and clusters where orange tortrix or omnivorous leafroller is a problem.
• In vineyards with a history of branch and twig borers, examine old pruning scars and dead parts of vines for brown frass and wood dust.
• If you have vine mealybug, steam sanitize equipment before moving to an uninfested area of the vineyard.

Survey weeds to plan a weed management strategy. If herbicides are used.

• Use the late-winter survey form (PDF) to record your observations and make pre- and postemergence herbicide selection decisions.
• Remove leaves and debris under the vine before applying herbicides.
• Do not make preemergence herbicide applications if heavy rains are expected soon after application. However, applications should be made when a rain event of 0.25-0.50 inches is expected within 2-3 weeks.
• If possible, make preemergence herbicide application after dormant activities, such as pruning, are completed to reduce soil movement.