by Tamara Scully
While there may be numerous species of grapes growing, there is limited biodiversity, yet field edges and other areas of use on the farm may provide a variety of habitats. Often, they are designed to attract beneficial insects or provide wildlife habitat. While this strategy is not to be dismissed, it’s positive effects can be limited. Utilizing cover crops in the rows, mulching with organic materials, or planting flowering plants or a cash crop between rows of grapes are some techniques to further enhance vineyard biodiversity.
Doing so not only provides large ecosystem benefits, attracting a variety of insects and allowing native or functional plants to grow in agricultural landscapes, it also enhances the soil health and decreases pest and disease concerns, reducing the amount of chemical crop protectants required. Reduction in the weed population can also be achieved.
And enhancing soil biodiversity has been shown to improve the aroma and flavor of wine grapes. A wider variety of soil microbes enhance the flavor of the fruit, adding another level of terroir to the wine.
There are many programs that can provide guidelines, resources and even certification for growers wishing to increase vineyard sustainability. On the east coast, Cornell’s VineBalance offers a self-assessment workbook, grower resources and action plans. On the west coast, the California Sustainable Winegrowing Alliance and the Oregon LIVE program both offer third-party certification in sustainable vineyard and winery management. Other programs exist across the nation.
In a presentation at the 2015 LIVE annual meeting, Matt Shinderman, of Oregon State University Cascades, spoke of developing agricultural site-specific strategies which mesh with the larger, landscape-level ecosystem regions as being “the next challenge of conservation.”
“If you create some native habitat patches on farms, you increase the potential that you can attract beneficial insects, Shinderman said. “There is definitely a benefit to doing biodiversity enhancement, or vegetative enhancement, in vineyards.”
Large agricultural landscapes – working lands where human interaction is shaping the ecology – are ripe for even more intensive conservation measures. By implementing site-specific conservation measures, which also connect to the surrounding landscapes, eco-region enhancement can be achieved.
But on-farm measures to enhance biodiversity tend to focus on the farm independent of its neighboring lands. By rethinking this strategy and connecting the farm back to the larger-scale eco-region, ecological theory and practice can be incorporated across managed landscapes.
On farms where field edges are used to plant native flowers and attract beneficial insects, the positive results decrease as one moves further into the field center. More pest and disease pressures are seen here than in the crops in closer proximity to the beneficial habitat.
“If we want to have organisms move across a property, then we have to think about incorporating habitat patches throughout that property,” Shinderman said.
Looking at the landscapes surrounding the vineyard, and finding a way to connect conservation practices across a diversity of working lands is the key to this biogeographic approach. It doesn’t do much good – at least not beyond the vineyard itself – to build habitat for bees, or bats, or other native species if they are trapped there, if no other habitat is available nearby.
Increasing diversity requires “proximity to the next similar patch of native vegetation,” Shinderman said.
Beyond the need to connect patches of restoration so that the impact is felt across the “acres and acres of vineyard,” and furthermore to connect the vineyard to the surrounding lands, selecting the correct species – both plants and animals – which can thrive in a working landscape, is critical.
“Which species have relevance for vineyard settings? We’re talking about working landscapes.”
Species that are sensitive to disturbances are probably not the best ones to select for re-introduction into the farm landscape, he said. Strategy species, both plants and animals, are those which are not only appropriate for the eco-region in which he farm exists, but for the farm itself. Site specific details, such as knowing where are people living and working, where is the equipment moving, what areas are undisturbed and what features are there, as well as knowing what vegetation already exists on and surrounding the property, is needed.
Eco-regions and Site Specifics
Within an eco-region many species of flora and fauna thrive. The three key elements of any eco-region are: climate; soils; and topography.
“These three things differentiate ecosystems more than any other items, “Shinderman said.
Yet there are “much finer-scale complexity and variability” which exists throughout any eco-region. Native plant lists for a region “don’t tell us about what will work on a specific site,” Schinderman said.
Selection of species for restoration on working lands is compounded by the fact that little is known about many of these species. Some factors, such as the species’ dispersal – how far does the insect travel for food, and what else must be available in that area, for example – are important qualifiers.
Shinderman points to the availability of high-resolution aerial photography and GIS mapping as examples of technology that can greatly assist in looking at biodiversity across larger landscapes. This provides the opportunity to design conservation projects not only to promote biodiversity on the farm itself, but throughout the eco-region.
More data is needed to find the plants that have “the most promise and potential benefit for natural habitat enhancement,” he said, and to create a more strategic approach to restoration efforts.
“We want these to be healthy, functioning, economically productive landscapes…and still support biodiversity,” Schinderman emphasized. “This is just one approach. There are a lot of different ways we can approach this subject of on-property enhancement.”
Agricultural properties are working lands. Knowing site-specific details of production and other land uses, and selecting areas for restoration based around that activity, is imperative. Connecting these areas, as well as introducing native species which have the best ability to thrive there, to improve the site’s ecology, and to be incorporated into the larger surrounding landscapes, are key to moving beyond isolated biodiversity to improvements to larger, regional landscapes.
Working landscapes and vineyard biodiversity
by Tamara Scully