The FFAR-Pollinator Project is held by Williams Lab, UC Davis Student Farm, and Hedgerow Farm, and sponsored by the Foundation for Food and Agricultural Research. The aim of the Pollinator Project is to conserve the biodiversity of native pollinators and support sustainable agriculture through the development of a wildflower seed pack. Through these efforts we strive to offset the negative effects on pollinators caused by agricultural intensification, pesticide overuse, and pathogen exposure.
The experimental site is on the UC Davis Student Farm, manifesting in 120 2x2m plots at the west end of the Market Garden. These plots were seeded with 28 native wildflower species and 2 grass species with different species richness and seed density. This study will examine this richness and density to study the establishment of plant species, total floral area generated, and weed presence, then use that data to create cost-effective seed mixes to attract wild pollinators to provide pollination services for agricultural field.
Preparation and Management
To prevent unwanted plants and weeds from growing in the experimental plots, the soil on the site was solarized prior to seeding. The plots were covered with a white plastic tarp which trapped in heat from the sun, creating a greenhouse effect. This greenhouse effect heated up the space between the tarp and soil and the first few centimeters of the soil itself, killing any heat sensitive foreign seeds.
A total of 120 seed mixes, hence 120 experimental plots, were used in this project. Within these 120 seed mixes are:
- Three levels of plant species richness
- high, medium, and low — 24, 12, and 9 species accordingly
- Three levels of seeding density
- high, medium, and low — 90, 45, and 22.5 seeds per square feet accordingly
- Inclusion of grass to help raise seeding densities to medium/high
- wildflowers only
- wildflowers and grass
Dividing Plots, Weeding, and Waiting for Bloom
The first step of data collection is identifying the plant and weed species in the plots. Then the blooming flowers for each flower species are counted in two 1m x 1m quadrats in each 2m x 2m plot, and an estimate percent cover for grass and weeds is generated. This data will be used to determine if each plant species can easily establish colonies, if it can compete with weeds, and if it has a large floral area which can provide enough food for visiting bees.
Ecological and Social Meanings
California’s diverse ecosystems and agricultural industries run on the labor of pollinators, however, continued development is diminishing and fragmenting native pollinator habitat, and billions of dollars of farmland rely on an European honey bee system in danger of collapse. To provide resilience to California’s farming industry more pollination options are crucial. Planting native wildflowers serves to both support our diverse system of pollinators and ensure agricultural pollination can continue if honey bee hives decline (Lundin 2019). Through this research the Williams Lab aims to assemble an economically viable seed mix that farmers can use to attract bees and support their crops.
Lundin, O., Ward, K. L., & Williams, N. M. (2018). Identifying native plants for coordinated habitat management of arthropod pollinators, herbivores and natural enemies. Journal of Applied Ecology, 56(3), 665–676. doi: 10.1111/1365-2664.13304