- Author: Rhonda J Smith
- Contributor: Akif Eskalen
For the first time many growers are facing the dilemma of what to do with fruit that will not be sold. Although wine inventories have been slowly building over the past few years, 2019 is the first year in which a number of growers are feeling the effects of excess supply due to the large 2018 crop.
Given that yields thus far for most growers have been “average” or better and there is significant unsold inventory of bulk wines, custom crushing uncontracted grapes in 2019 may not be a viable option. Hopefully there will be buyers as the harvest continues but in this market, the prices offered are likely to be less than the cost of production.
Allowing unsold fruit to remain on the vines may seem unthinkable yet with no income from those blocks, it makes sense. This means not dropping clusters by hand and not running a harvester in the vineyard to get the berries off.
From the perspective of a plant pathologist:
clusters that decompose over the winter - either on the vine or on the ground -
are not likely to have a noticeable effect on fungal disease pressure the following year given common vineyard floor management practices.
All common grapevine fungal pathogens exist inside vineyards. For example, fallen petioles, rachises that remain on the vine after mechanical harvest, pruning debris and woody tendrils that cling to trellis wires all support the growth of fungi. These fungi act as sources of inoculum that can infect wounds caused by pruning and suckering, and infect berries at bloom and other green tissue.
The fungi that colonize decaying berries include the same fungi seen growing on damaged berries before harvest including Botrytis cinerea and Cladosporium and Aspergillus species which are associated with Botrytis bunch rot, Cladosporium rot and sour rot respectively. Fungi can infect then colonize the ripening berries when spores enter through the slightest opening in the berry cuticle caused by sunburn or the presence of diffuse, unseen powdery mildew. Berries are an overwintering structures for these fungi and others.
Botrytis cinerea spores are ubiquitous given the fungus can survive on dead tissue as well as infect living tissue. It grows on dead calyptras (flower caps) and stamens after bloom and will infect a young berry through the wounds left when the cap is shed. In various studies, Botrytis sporulation in the lab occurred on petioles and rachises collected on the ground and remnants of rachises collected from canes after pruning.
- Eliminating pruning debris will remove the inoculum formed on decomposing clusters and pieces of canes prior to bud break. Vineyard access to alternate rows is required to incorporate last year's wood and cluster remnants while maintaining resident vegetation or a sown cover crop in the non-tilled rows.
All common grapevine fungal pathogens exist inside vineyards and the relative importance of allowing unsold fruit to remain on the vines should be put into perspective of other vine tissues that are also decomposing. Clusters that remain in the vineyard are not likely to have a noticeable effect on disease the following year if common vineyard floor management practices are followed.
Acknowledgement: Valuable input provided by Dr. Akif Eskalen, Cooperative Extension Plant Pathologist, UC Davis.
- Author: Julia Van Soelen Kim
Two years ago today, Sonoma County residents awoke to fire spreading through urban and wild lands across our county, a dark cloud of smoke covering the sky, and ash blanketing the ground. There continues to be much work for our community to collectively recover from the fires--most of it is hard and heavy work, whether it be emotional work, community work, economic work, environmental work. UCCE Sonoma's Produce Safety after Urban Wildfire: Citizen Science Initiative is just one small piece of that body of work.
The project sought to find out if garden and farm-grown produce exposed to ash was safe to eat, mobilized community in the days and weeks after the fire to collect leafy greens from sites across the county for later analysis, formed a unique partnership between UCCE Sonoma, Petaluma Bounty, and a passionate public health researcher, Vanessa Raditz, and ultimately led to a workshop series, a newly published scientific report, a forthcoming toolkit for other communities affected by wildfire to assess the safety of their own unique context, and a collaboration with researchers from UC Davis School of Veterinary Medicine to investigate the safety of backyard chicken eggs in fire affected counties.
Today we honor the terrible toll of the fire on this community, and we welcome your participation in our upcoming Post-Fire Food Safety Workshop as a small piece of recovery and learning for the future. The workshop will be held on Thursday, Oct. 17, 2019 from 6:00pm-8:00pm at the Environmental Center of Sonoma County, 55 Ridgway Ave., Santa Rosa, CA 95401. Refreshments will be provided. RSVP at ucanr.edu/postfirefoodsafety10.17.19
- Author: Phil McRea, Master Gardener
- Contributor: Karen Giovannini
Updated links and republished Oct 2019.
Many residents in Sonoma County live in or near fire danger. For those who do live in a high fire area, knowing what to do when conditions are ideal for a forest (or urban fire) is essential.
Red Flag Warning
- Sustained wind speeds averaging 15 mph or greater
- Relative humidity 25% or less
- Temperature over 75 degrees F
Fuel Moisture Index
The fuel moisture index is a tool used to understand fire potential. 10-hour fuel moisture also known as Dead Fuel Moisture; when fuel moisture is <30%, it is essentially considered dead. 10-hour fuel moisture applies to grasses and bushes up to 1 inch in diameter. Learn more at NOAA.
The US National Weather Service warning is to inform area fire fighters and land management agencies that conditions are ideal for wild-land fire combustion. Cal Fire and local fire agencies all go on a high alert status under these conditions.
The Wind Cries...Santa Ana or Diablo?
The Santa Ana and Diablo winds occur throughout the year, but are extremely dangerous during dry periods (which, in Southern CA is practically year round). Santa Ana occurs in Southern CA, Diablo in the north. Winds come from the east from hot surfaces (deserts) and are compressed and speed up as they head towards the ocean. Learn more from SFSU. Check out current wind conditions at Windy.com.
Be Prepared
Here are some things you can do when Red Flag Warnings are issued. State and local news agencies usually announce Red Flag Warning 24-48 hours in advance on TV and radio, so there is time to act on short-term fixes.
During Fire Season
- Make sure garden hoses are hooked up and ready to use with spray nozzles attached; best practice is to never leave a garden hose randomly piled up as it will always tangle – if you want it coiled, coil it in equal sized oval loops with each successive loop offset few inches in the same direction.
Garden hose ready to use - All portable propane tanks (BBQ, smoker, etc.) should be turned off and moved away from your house.
- If you have a pool: in an emergency, a pressure washer can be used to pump water from your pool and should be left in an available location; fire fighters should have clear access to your pool.
- Decks should be cleared above and below of flammable objects.
- Gas cans – for lawn mowers, chippers, whatever – should be moved away from house or garage/barn.
- Cover firewood stacks next to house with a fire resistant cover.
- Make sure cell phones are charged and ready for alerts and within hearing at all times.
- Close exterior doors and windows. Leave doors unlocked. Leave lights on inside and outside of house.
- If you have a ladder, leave it available outside, next to the house, in case fire fighters need to access roof.
- Have all your evacuation supplies such as flashlights and a good portable radio ready to go.
- Make sure your cars have plenty of gas and are parked outside, or garage door is capable of manual operation and all capable family members know how to open it.
- If appropriate, shut off gas supply line at the meter.
Ongoing Preparations
- Make an evacuation plan and collect all necessary supplies.
This gutter needs some cleaning - Clean gutters and roof debris regularly.
- Where possible, install mesh screening under decks to prevent burning material from blowing.
- Move firewood piles away from house.
- If you have a pool, research the special pump systems that are available for fire fighting.
- For more information obtain a free brochure: “Living with Fire in Sonoma County” from fire agencies of Sonoma County.
Learn more about disaster preparation and recovery on Disaster Recovery Resources.
- Author: Steven M. Worker
Through qualitative questionnaires and focus group interviews, we analyzed experiences of 6 new bilingual and bicultural program staff, hired specifically to implement youth development programming to reach Latino youth. Staff reported a steep learning curve, with competing demands to build relationships, engage youth, and show results. Lessons learned may help shape activities that other youth development programs may consider in similar efforts.
"Staff emphasized that getting to know the community and building relationships were the most important parts of starting a new 4-H program. Staff identified several 4-H program models they utilized to engage Latino youth in 4-H; these included after-school clubs, SPIN clubs, in-school clubs, day camps, and short-term/special interest programs."
Sonoma County offers After School Clubs and Day Camps when schools are out. These clubs are in Santa Rosa and Windsor. To learn more about these clubs, contact Diego dmariscal@ucanr.edu
To learn more about this report, contact Steven smworker@ucanr.edu
- Author: Karen Giovannini
We are pleased to welcome Cindy Kron, PhD as our Area Wide IPM Advisor for Sonoma, Napa, Mendocino and Lake counties.
Cindy has conducted research on a variety of insects including:
- two-year vineyard study on the population dynamics of Virginia creeper leafhopper, western grape leafhopper, and variegated leafhopper
- dissertation research projects investigating the biology and behavior of the three-cornered alfalfa hopper and their relationship with vineyards
- the effects of temperature on the developmental rate of the invasive European grapevine moth
- rearing brown marmorated stink bugs for USDA fumigation studies
Between UC Davis and UCCE, Cindy continued her study of the three-cornered alfalfa hopper as a Research Entomologist for USDA in their Crop Disease, Pests, and Genetics research unit. She tested additional cover crop species as feeding and reproductive hosts of the three-cornered alfalfa hopper in addition to testing commercially available biocontrol agents against the different life stages of the treehopper. She collaborated with a UC Davis colleague to create a degree day model that predicts the ideal timing to implement cultural control measures with the greatest impact on treehopper populations.
“My experiences have motivated me to help growers, stakeholders, and the industry solve agricultural pest management problems through applied research by identifying IPM strategies and tactics that are economically feasible and implementable while having the lowest environmental impact.”
When she is not working with insects, Cindy loves wine tasting, gardening, cooking and canning. She's come to the right place for ALL of that.
Welcome to Wine Country, Dr. Cindy Kron!
