Farm Information

County: Napa
Location: Oakville AVA
Slope: Some areas are flat, other areas are between 5-15% slope
Irrigation system: Drip
Soil type: Gravelly loam
Soil detail: Boomer Gravelly Loam, Boomer Loam
Special farming challenges: There are some soil differences that affect the way the cover crop grows.

• Cropping Systems Information
• Crop: winegrapes
  Acres of orchard or vineyard: 23

  Other crops: No
  Acres of other crops: n/a
  Organic management: No
  Certifications: Napa Green, Fish Friendly Farming
  Certifications notes: n/a
  Where using cover crops: Vineyard

• Grower Experience, Farm Priorities, and Cover Cropping Goals
• When started farming (yr): 1986
  Farm priorities: To produce top quality grapes in a sustainable way.
  Years growing orchard or vineyard crop: 35 years
  Years growing cover crops: 35 years
  Initial transition to cover cropping: Since the beginning they have seeded cover crops in between vine rows in the entire vineyard.
  Goals and benefits: Soil improvement, nitrogen supplement, insect predator support
  Benefits description: Nitrogen fixing, pest control/enhance predator populations, erosion control, soil health/soil organic matter
  Change in goals over time: Besides the original thinking, they are now also interested in carbon sequestration.
  Reasons: Not much has changed. Over the years they have incorporated different cover crops in different sections of the vineyard to see what works best.
• Cover Crop Details, Planting and Management Methods

• Block described here: Winegrapes
  Current cover crops: Legumes, grasses
  Species and mixes: Triticale, oats, purple vetch, common vetch, peas.
  Planting method: Broadcast seed
  Planting date (2020): Mid October
  Was that optimal? They thought it was optimal because we seeded before the first rains but then they didn't get much water. Ideally they would like to planted ahead of substantial rains.
  Pre-plant soil prep: Disc
  Planting equipment: Broadcast seeder (tractor)
  Seeding rate: 100lb/acre
  Seeding depth: 0
  Did it germinate well? No. It germinated ok but compared to previous years it hasn't been growing that great.
  Additional management and advice: n/a

• Cover Crop Termination Methods and Biomass Management

• Termination method: Mow, disc
  Termination equipment and process: Mow with flail mower and then disc in.
  Termination date: Late March, beginning of April
  Was it optimal? Yes, we do it based on the dryness of the soil because we don't want the cover crop competing for water with the vines.
  Biomass management: Incorporated it into the ground in the cultivated rows, left it in place in the mowed rows.

• Cover Cropping Challenges and Strategies to Address Them
• Challenges: Risk of frost, establishment difficulties
  Challenges description: Risk of frost damage to vines, water availability/difficulties irrigating cover crop
  Strategies to address challenges: "We mow if we think a cooling event will happen."
  Was the cover crop worth it? Don't think that cover crop adds a substantial cost to the operation.​​​​​​​
  Least successful past cover crops: n/a