Effects of controlled disturbance within early-successional northeastern forest habitat: Evaluating soil quality, plant production, and economic feasibility

Project Overview

FNE12-751
Project Type: Farmer
Funds awarded in 2012: $14,976.00
Projected End Date: 12/31/2015
Region: Northeast
State: Massachusetts
Project Leader:
Kathleen Kerivan
Bug Hill Farm

Annual Reports

Commodities

  • Fruits: berries (other)
  • Additional Plants: native plants, trees

Practices

  • Crop Production: conservation tillage
  • Education and Training: demonstration, extension, on-farm/ranch research, workshop, technical assistance
  • Energy: energy conservation/efficiency, energy use
  • Farm Business Management: budgets/cost and returns, agricultural finance
  • Natural Resources/Environment: carbon sequestration, biodiversity, habitat enhancement, wildlife
  • Production Systems: permaculture
  • Soil Management: green manures, organic matter, soil analysis, soil microbiology, soil chemistry, soil quality/health
  • Sustainable Communities: local and regional food systems, new business opportunities, employment opportunities, sustainability measures

    Proposal summary:

    The Northeast region is heavily forested (see Carpenter, 2007; Butler et al., 2007). The majority of landowners in this region, including farmers, have some forestland on their property, whether it is maintained as native woodland or managed as a woodlot. Bug Hill Farm is among this generation — more than two-thirds of our land is forested. We are reaching a point where we need to expand our production to keep up with demand for our organic berry products, and we are forced to decide whether to expand production by leasing additional land in remote locations or by expansion into native forestland.

    We propose to employ techniques of agroforestry and permaculture to allow us to expand berry production into marginal, forested areas of our property while still managing these areas for the overall health of local forest ecosystems. More specifically, we propose to establish small, experimental plantings of perennial woody berry plants that are common in transitional ecosystems into early-successional forestland in order to determine which cultivation methods will produce the best balance between environmental sustainability and cost of production.

    Our project’s main research objective is to examine changes in soil quality as a direct effect of experimental land management and cultivation techniques, viz. maintaining land in an essentially arrested state of early-successional woodland and utilizing the high-carbon waste produced by such management practices in the construction of specialized sheet compost-cum-raised beds known as ‘Hugelkultur’.

    Outreach will be done through on-site workshops, presentations at NOFA confernences and and article in the Massachusetts Berry Notes Newsletter and our farm website.

    Project objectives from proposal:

    Bug Hill Farm is a values-driven enterprise, established out of a desire to become a model for environmental, agricultural, and social sustainability. This project is directly linked to our mission to serve as an educational center for visitors interested in the complementary aspects of ecological restoration and sustainable small-scale farming.

    The main research objective of this project is to examine changes in soil quality as a direct effect of experimental land management and cultivation techniques, viz.

    • Establishing small plantings of perennial woody berry crops that are common in transitional ecosystems — chokeberry, elderberry, and honeyberry — into early-successional habitat which has received treatments of varying levels of soil disturbance;

    • Maintaining land in an essentially arrested state of early-successional development to increase biodiversity and habitat for wildlife, including native pollinators; and

    • Recycling the high-carbon waste produced by such management practices through the construction of specialized sheet compost-cum-raised beds known as ‘Hugelkultur’.

    Secondary objectives include measuring plant growth as an indicator of health and future production value, and economic analysis of the costs associated with the execution of each treatment.

    Our experiment is distinguished by monitoring successional soil processes on land that has been allowed to grow as forest for several decades before disturbance. Results of this research will be used to determine which cultivation methods will produce the best balance between environmental sustainability, production value, and cost-effectiveness. Information and data generated by our project will be beneficial to any landowner that is considering utilizing forested land for agricultural production.

    The basis of our experiment is to create an experimental planting utilizing three different types of treatments (‘Control’, ‘Hugelkultur’, and ‘Successional’), which represent varying levels of soil disturbance (high, moderate, and low, respectively). All plots will be 50’ by 50’, and made out of forestland that has recently been felled for early-successional habitat. All plots will be relatively adjacent to one another on a uniformly level site which has been chosen to minimize pre-existing environmental variables. The three treatment types will be replicated twice, for a total of nine plots. Due to economic constraints and the difficulty of executing stump-removal in small, isolated parcels without disturbing surrounding areas, it is necessary for our control plots to be situated within a 1.5-acre area that is already scheduled for stumping next spring. Although this presents difficulties for randomizing the order of our plots, true randomization may be less critical in our experiment since our results will be determined by change over time within plots, rather than comparing absolute values of soil quality. Please see the attached plot plan for clarification.

    ‘Control’ plots represent a high level of soil and root disturbance. Plots will receive the following treatment:

    1) Stumps will be ground-down and woody debris will be removed by machinery;

    2) Land will be plowed and seeded with a cover crop of oats and field peas;

    3) Cover crop will be allowed to grow for one month;

    4) Plots will be tilled again; and

    5) Planted with berry crops.

    The debris removed from these plots will be utilized to construct hugelkultur beds in the second plot set. Under normal circumstances, this debris would require disposal; an estimate for such disposal will be obtained from a local contractor for economic analysis.
    ‘Hugelkultur’ plots represent a moderate level of soil and root disturbance. Hugelkultur construction process:

    1) Topsoil will be removed in broad, shallow furrows along rows and piled nearby, using machinery;

    2) Furrows will be filled to a depth of 1–2 feet with remnants of stumps, logs, and other woody debris which were cleared from the control plots and supplemented with woody materials from adjacent non-experimental parcels. Large or heavy materials will be moved by machine, other materials will be moved by hand;

    3) Wood will be covered with a layer of green compostable materials gathered from control plot waste and adjacent parcels;

    4) Organic materials will be covered over with the topsoil removed to create the furrows;

    5) Berry crops will be planted directly into the resulting mounds. See attached diagram for further explanation of hugelkultur construction.

    After the disturbance of initial construction, ‘Hugelkultur’ plots will be maintained in the same manner as the ‘Successional’ plots (see below).

    ‘Successional’ plots represent a minimum level of soil and root disturbance. Plots will be maintained as early-successional habitat, stumps and other woody debris and native plants will not be removed and will be maintained in an essentially arrested state of early-successional development. Regenerating trees and shrubs will be selectively cut back after reaching 4 feet in height to maintain spatial and temporal heterogeneity. We will dig between stumps and young and regenerating shrubs and trees to plant berry crops.

    Plots are to be planted with three species of woody perennial berry crops, chosen for their production value and ability to grow naturally in early-successional habitats — specifically: native black chokeberry (Aronia melanocarpa (Michx.) Ell.) ‘Viking’, American elderberry (Sambucus canadensis L.), and honeyberry (Lonicera caerulea L.). Although there is a subspecies of honeyberry native to North America, its production value is inferior to cultivars developed throughout northeast Asia (see Bors, SK-S7N-5A8; Bors, 2010); we will be using two cultivars developed by the University of Saskatchewan breeding program, ‘Tundra’ and ‘Borealis’. Ten of each species will be planted in each plot, in rough rows; honeyberry rows will receive five specimens of each cultivar.

    Our experiment is designed to incorporate agroforestry practices that embody the four ecological principles of natural ecosystems highlighted by Olson et al. (2000): 1) spatial and temporal heterogeneity is achieved through maintaining early-successional habitat as an intermediary between forest and field; 2) controlled disturbance of soil and successional processes is the primary determinant of structure and function in the system; 3) the ecosystem will be dominated by woody perennials, including selected crops; and 4) ecosystem performance and efficiency will be increased by structural and functional diversity through creation of native pollinator habitat and management for production (see also LS05-174).

    Once the plots are established, additional work will include:

    - Regular care and maintenance of plants;
    - Seasonal flower and berry harvesting;
    - Regular soil health testing; and
    - Plant growth measurements.

    The experiment will be conducted over the course of three years as the changes in soil health and composition which we will be monitoring tend to happen slowly over time, and a longer time-frame for data collection will also provide more meaningful results in the face of uncontrollable environmental variables like weather (see FNE06-580).

    We will ensure that all other treatments to these plots over the course of the experiment, including any addition of compost, organic fertilizers, mulching materials, etc. will be replicated identically in each plot.

    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.