Posts Tagged: cover crops

Growers invited to see benefits of cover crops in orchards, vineyards

 

Searchable database of growers experienced in growing cover crops launched

Growers are invited to tour orchards and vineyards and hear from other growers about their experiences with cover crops. 

UC Sustainable Agriculture Research and Education Program, UC Cooperative Extension, the Napa Resource Conservation District, and the Community Alliance with Family Farmers have created a searchable database of orchard and vineyard growers experienced in growing cover crops that will help other growers bring the benefits of the practice to their operations. 

“The tours are part of a project for which we recently unveiled new tools for orchard and vineyard growers to learn about cover cropping from experienced growers,” said Sonja Brodt, associate director of the UC Sustainable Agriculture Research and Education Program. 

The database describes cover cropping strategies, details of field practices, benefits and challenges experienced by cover crop growers in orchards and vineyards in the southern Sacramento Valley (including the Capay Valley) and the North Coast viticulture region. The cover crop grower database is available at https://sarep.ucdavis.edu/covercropsdb.

Feb. 8, 1-5 p.m., Capay Valley tour: 

The tour will visit three organic farms in the Capay Valley that are integrating cover crops and grazing in their orchard and vineyard systems. Topics of discussion will include:

• Strategies for integrating cover crops into orchards and vineyards
• Impacts of cover cropping and grazing on soil health
• Funding and information resources for growing cover crops

Speakers will include:

• Rory Crowley, Director of Habitat Programs, Project Apis m.
• Amélie Gaudin, Associate Professor, Department of Plant Sciences, UC Davis, Endowed Chair in Agroecology
• Hope Zabronsky, Climate-Smart Agriculture Program lead, UC Agriculture and Natural Resources

To register for the Feb. 8 tour, visit https://sarep.ucdavis.edu/events/grazing-cover-crops-orchards-and-vineyards-capay-valley-tour.

March 8, 1-4 p.m., Arbuckle area tour: 

The tour will visit two conventional farms in the Arbuckle area that are integrating cover crops into their orchard and vineyard systems. 

Topics of discussion will include:

• Strategies for integrating cover crops into orchards and vineyards
• Impacts of cover cropping on soil and water balance
• Frost risk protection and prevention
• Funding resources for growing cover crops

Speakers will include:

• Rory Crowley, Director of Habitat Programs, Project Apis m.
• Kosana Suvocarev, UC Cooperative Extension Specialist in Biometeorology, UC Davis Department of Land, Air, and Water Resources
• Hope Zabronsky, Climate-Smart Agriculture Program lead, UC Agriculture and Natural Resources

To register for the March 8 tour, visit https://sarep.ucdavis.edu/events/cover-cropping-conventional-orchards-and-vineyards-arbuckle-area-tour

New UC study helps growers estimate cover crop costs and potential benefits

Cover crops offer many potential benefits – including improving soil health – but not knowing the costs can be a barrier for growers who want to try this practice. To help growers calculate costs per acre, a new study on the costs and potential benefits of adding a winter cover crop in an annual rotation has been released by UC Agriculture and Natural Resources, UC Cooperative Extension and the UC Davis Department of Agricultural and Resource Economics.

Led by UC Cooperative Extension farm advisors Sarah Light and Margaret Lloyd, the cost study is modeled for a vegetable-field crop rotation planted on 60-inch beds in the lower Sacramento Valley of California. Depending on the operation, this rotation may include processing tomatoes, corn, sunflower, cotton, sorghum and dry beans, as well as other summer annual crops.

“This cost study can be used by growers who want to begin cover cropping to determine the potential costs per acre associated with this soil-health practice,” said Light, a study co-author and UC Cooperative Extension agronomy advisor for Sutter, Yuba and Colusa counties.

“Based on interviews with growers who currently cover crop on their farms, this cost study models a management scenario that is common for the Sacramento Valley. In addition, growers who want to use cover crops can gain insight as to what standard field management practices will be from planting to termination.”

At the hypothetical farm, the cover crop is seeded into dry soil using a grain drill, then dependent on rainfall for germination and growth.

“Given the frequency of drier winters, we included the cost to irrigate one out of three years,” said Lloyd.  

A mix of 30% bell bean, 30% field pea, 20% vetch and 20% oats is sown in the fall. Depending on winter rainfall, soil moisture and the following cash crop, the cover crop is terminated in mid to late spring. The cover crop is flail mowed and disced to incorporate the residue into the soil.

The study includes detailed information on the potential benefits and the drawbacks of cover cropping.

Another consideration for growers is that multiple programs such as CDFA's Healthy Soils Program, various USDA-funded programs (EQUIP, the Climate-Smart Commodities, etc.), and Seeds for Bees by Project Apis m. offer financial incentives for growers to implement conservation practices, such as cover crops.

“This study can provide growers with a baseline to estimate their own costs of using winter cover crops as a practice. This can be useful to calculate more precise estimates when applying for some of these programs and/or weigh the costs per acre with expected benefits in terms of soil health, crop insurance premium discounts or other benefits provided by the cover crops,” said Brittney Goodrich, UC Cooperative Extension agricultural and resource economics specialist and study co-author.

“Last year, the USDA's Pandemic Cover Crop Program gave up to a $5/acre discount on crop insurance premiums for growers who planted a cover crop, and there is potential this will get extended going forward,” Goodrich said. 

A list of links to resources that focus specifically on cover crops is included in the study. Five tables show the individual costs of each cultural operation from ground preparation through planting and residue incorporation.

The new study, “2022 - Estimated Costs and Potential Benefits for a Winter Cover Crop in an Annual Crop Rotation - Lower Sacramento Valley,” can be downloaded from the UC Davis Department of Agricultural and Resource Economics website at coststudies.ucdavis.edu. Sample cost of production studies for many other commodities are also available on the website.

This cost and returns study is funded by the UC Davis Department of Agricultural and Resource Economics.

For an explanation of calculations used in the study, refer to the section titled “Assumptions.” For more information, contact Don Stewart in the Department of Agricultural and Resource Economics at destewart@ucdavis.edu, Light at selight@ucanr.edu, or Lloyd at mglloyd@ucanr.edu.

Farmers invited to tour cover crops in Sacramento Valley March 3

Farmers and ranchers are invited on a tour to learn how to use cover crops to build soil health. A full-day tour of several cover crop sites in orchards and annual crop fields in the Sacramento Valley is being offered on March 3 by the Western Cover Crop Council's Southwest Region Committee.

“The goal of this tour is to demonstrate ways to use cover crops effectively in annual crops and orchards in the Sacramento Valley,” said tour organizer Sarah Light, UC Cooperative Extension agronomy advisor.

“This tour will cover a range of topics, including cover crop selection, equipment needed to manage cover crops, considerations for cover cropping in the region, and the importance of building soil health,” said Light, who is also chair of the Western Cover Crop Council's Southwest Region Committee and a board member of the Western Cover Crop Council.

Cover crop species, cultivars and mixes including legumes, grasses and brassicas will be showcased in Colusa County, with farmers, UC Cooperative Extension specialists and researchers giving presentations.

The tour bus will depart from the Colusa County Cooperative Extension Office at 100 Sunrise Blvd., Suite E, Colusa, CA 95932 at 8 a.m. and return at 7:30 p.m.

Participants are currently limited to 50 farmers and ranchers. If space is available after Feb. 1, others may join. ?The $50 registration fee includes morning refreshments, transportation, lunch and dinner. To register or to see the agenda, visit https://surveys.ucanr.edu/survey.cfm?surveynumber=36190.

Can California native plants be used as cover crops to benefit farmers and native ecosystems?

In late February, in an almond orchard in the Sacramento Valley, the fall-planted cover crop mix of grasses, brassicas and legumes had barely produced a green fuzz above the soil surface, and it was unclear when it would bloom. Unfortunately, this scene is becoming more frequent across California, as climate change causes more prolonged droughts and rain-dependent winter cover crops can barely grow, which delays or reduces bloom, essential for supporting pollinators. Fortunately, California native plant species have evolved with drought and have developed many strategies to survive and reproduce in those conditions.

Would it be possible to capitalize on the over 9 million acres of cropland in California for drought resilience and habitat restoration by utilizing more native species as cover crops? Our team at the UC Sustainable Agriculture Research and Education Program (UC SAREP) spent some time considering various native plant species and their potential ecological and operational attributes as cover crops. For a full list of species and their attributes, see https://ucanr.edu/sites/covercrops/.

Many native species are so well adapted to drought that they will still germinate and bloom during extremely dry years, for example, annuals like Tidy Tips (Layia platyglossa) and California poppy (Eschscholzia californica). Alternatively, perennial bulb species like Prettyface (Triteleia ixioides) and Bluedicks (Dipteronstemon capitatus) become dormant during the dry summer, retaining their bulbs below ground and re-growing when the rains return. These species could perhaps fit well in no-till orchard systems. Summer dormancy is important for tree nut growers because they usually need clean ground under the trees during harvest. Moreover, the costs to terminate and reseed would potentially be eliminated. While these species are well-known by Native Americans for their edible bulbs, at this point in time, we are not aware of any cover cropping trials having ever been conducted with these species. 

Another species with strong reseeding and more availability is the annual Lacy Phacelia (Phacelia tanacetifolia), which offers an intriguing historical precedent for developing a native species for cover cropping purposes. Native to California, it was introduced into Europe in 1832 by Germans. It is very attractive to pollinators and experienced a boom there in the early 1990s. European beekeepers and farmers have been using Lacy Phacelia as a cover crop ever since, and it has recently been gaining traction on California farms as well. California has many species of phacelia, with another, described as being even more attractive to native bees, being the annual Great Valley Phacelia (Phacelia ciliata). Besides supporting native bees, other native plant species can contribute nitrogen to the soil, such as annual Lupine (Lupinus spp.) and perennial Deerweed (Acmispon glaber), which are legumes and form an association with nitrogen-fixing bacteria in their roots.

Cover crops are not usually considered marketable crops. However, we should not preclude the potential for some plants that are useful as cover crops to provide a harvestable product as well. Native perennial fiber plants such as Indian hemp dogbane (Apocynum cannabinum), narrow leaf milkweed (Asclepsias fascicularis), and common nettle (Urtica dioica) could offer the opportunity to cultivate summer cover crops that have a market value, especially in cases where farmers are already willing to irrigate their cover crops to improve their development and amplify the benefits. Bowles Farming in the San Joaquin Valley is experimenting with growing these three species for fiber production. All three also attract native bees and important butterfly species such as monarchs (as long as farmers avoid spraying insecticides). 

While we believe that some native species could open new opportunities for farmers as cover crops, we still have insufficient studies testing the effects and viability of these species. Organizations like the NRCS Plant Materials Center at Lockeford and the Xerces Society are conducting practical studies with native species, creating plant guides and working with farmers to expand their use. In addition, researchers Lauren Hale of the USDA Agricultural Research Service and Anil Shrestha of California State University, Fresno, are using a 2021 UC SAREP small grant to study the effects of native species mixes on water demand and weed populations in San Joaquin Valley grape vineyards. Hale suggests that below-ground ecosystems may benefit as much from native plants as above-ground ecosystems. Says Hale, “Because plants and their microbiomes have evolved together for millennia, it seems logical that native plants would promote a good response from the native soil microbiota.”

For additional information:

UC SAREP List of California Native Species for Potential Use as Cover Crops: https://ucanr.edu/sites/covercrops/

Xerces Society lists of pollinator-friendly native species for California: https://xerces.org/pollinator-resource-center/california

NRCS California Plant Materials Center plant guides: https://www.nrcs.usda.gov/wps/portal/nrcs/publications/plantmaterials/pmc/west/capmc/pub/

UC SAREP Cover Crops Database: https://sarep.ucdavis.edu/covercrop

Cover crop management in walnut orchards: from low-input groundcover to forage intercrop

Over the last few years, UC Davis Weed Science has been testing cover crops for weed suppression in nut orchards. The most recent project we've been working on has trialed several cover crop programs using cereal rye in walnut orchards. These cover crop programs represent a range of several...

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