Enhancing Hedgerow Systems in Fruit Tree Production to Improve Beneficial Insect Diversity and Abundance

Project Overview

LS20-342
Project Type: Research and Education
Funds awarded in 2020: $311,118.00
Projected End Date: 03/31/2023
Grant Recipients: University of Florida; University of Georgia
Region: Southern
State: Florida
Principal Investigator:
Dr. Xavier Martini
University of Florida
Co-Investigators:
Dr. Michael Andreu
university of Florida
Brett Blaauw
University of Georgia
Dr. Lauren Diepenbrock
University of Florida
Rachel Mallinger, Dr.
University of Florida

Commodities

  • Fruits: citrus, peaches
  • Animals: bees

Practices

  • Natural Resources/Environment: hedgerows

    Proposal abstract:

    Hedgerows have been used in different fruit tree production systems to protect groves against adverse climatic conditions such has strong winds and freezing events. However, attention has shifted to the potential of hedgerows in providing shelter and additional food resources to beneficial insects, in particular natural enemies and pollinators.

    Citrus and peaches are the two main fruit crop productions of Florida and Georgia. In citrus, hedgerows have been used to prevent the arrival of citrus canker spores, and to prevent wind damage on fruits and trees. We propose to improve the existing hedgerow system already present in Georgia and Florida along citrus and peaches orchards to enhance beneficial insect populations. Existing hedgerows present in cooperative farmer orchards will be enhanced by mid-size bushes, flowering vines and wildflower strips. Response of these treatments on the density and diversity of natural enemies (especially ladybeetles) and pollinators will be investigated over the course of two years. In addition, the potential reduction of fruit pests such as Asian citrus psyllids, aphids, and scales within orchards bordering these hedgerows will be measured.

    The other objective will be to investigate the effect of hedgerow connectivity and architecture on beneficial insects. Previous studies demonstrated that a network of hedgerows increases pollinator density and facilitates the movement of natural enemies. We will conduct a landscape-scale survey from Florida to Georgia where ladybeetles will be collected within and adjacent to hedgerows, and their density correlated to landscape features including hedgerow size and height, connectivity with other hedgerows, or connectivity with forest patches. With GIS technology, we will correlate natural enemy’s density to hedgerow landscape architecture.

    An outreach program will be developed with cooperative farmers. Field days will be organized to visit the orchards with improved hedgerows. Pre and post surveys will be conducted to better understand farmers’ willingness to erect or conserve hedgerows and any barriers to these actions.

    The outputs of this project will be the improvement of hedgerows as a refuge and food source for beneficial insects and subsequent enhanced pest suppression. Additionally, an output will be farmer education related to hedgerow design and conservation.

    The impacts of this project will be an increasing use of hedgerows in fruit tree production in Florida and Georgia, increased biological control in fruit orchards, the reduction of insecticide applications, and increased pollination. In addition, as an increasing number of farmers are adopting hedgerows, water and soil conservation within the region will be improved.

    Project objectives from proposal:

    1-      To increase diversity and complexity of existing hedgerow systems and measure their impact on pollinator and natural enemy density and diversity

    Hypothesis: Addition of flowering plants to existing hedgerows will increase density and diversity of pollinators and natural enemies.

    2-      To assess the effects of improved hedgerows on pest abundance and rates of herbivory.

    Hypothesis: Addition of flowering plants to existing hedgerows will improve biological control of major citrus and peach pests.

    3-      To investigate the effect of hedgerow connectivity on beneficial insect abundance and diversity.

    Hypothesis: Increasing connectivity between hedgerows will increase density and diversity of pollinators and natural enemies

    4-      Educate growers on the need for hedgerow conservation with workshop and field days.

    Hypothesis: Growers will be willing to include flowering plants in their existing hedgerows, will conserve existing hedgerows, and will plant new hedgerows to increase their connectivity.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.