Maximizing the effectiveness of cover crop rolling/crimping for improved weed suppression in no-till organic systems

Project Overview

Project Type: Research Only
Funds awarded in 2023: $199,999.00
Projected End Date: 11/30/2026
Grant Recipient: Rodale Institute
Region: Northeast
State: Pennsylvania
Project Leader:
Dr. Madhav Dhakal
Mississippi State University


  • Agronomic: corn, hemp


  • Crop Production: conservation tillage, cover crops, no-till
  • Education and Training: demonstration, display, extension, technical assistance, workshop
  • Pest Management: allelopathy, cultural control, integrated pest management, mulches - killed, weed ecology
  • Production Systems: agroecosystems, organic agriculture

    Proposal abstract:

    Cover crops (CCs) are an integral part of the weed management package in rotational no-tillage-based organic crop production systems. We propose a novel research project to support farmers in the Northeast by improving CC rolling/crimping technology in rotational no-till systems. This 3-year project will address USDA-SARE’s vision: “Agriculture in the Northeast will be diversified and profitable, providing healthful products to customers (….)” by improving weed suppression with no additional fuel, labor, and cost, promoting two specialty crops to diversify mid-Atlantic agriculture, and promoting organic crops to provide healthful products to customers. The project is conceptualized and designed based on stakeholder inputs. High bounce-back of CC after rolling/crimping, delayed response to crimping, and unbearable weed pressure even with substantial CC biomass are the key problems this project intended to address. Thus, two-year novel research will be conducted in two USDA plant hardiness zones (5b and 6a) during 2023-2025 to investigate the effect of rolling/crimping patterns on CC termination, cash crop establishment, weed dynamics, and allelopathic effect with three cover crops [cereal rye (Secale cereale), hairy vetch (Vicia villosa), and crimson clover (Trifolium incarnatum)] in no-till organic sweetcorn and fiber-hemp. The experiment will be laid out in a split-plot arrangement with 9 treatments plus one no-CC control with four replications. Main plot will have three rolling/crimping patterns with respect to CC rows (parallel, perpendicular, and 30º angled) and subplots will be randomly allocated to three CC species. Cover crops will be terminated using a roller/crimper, and simultaneously no-till planted with cash crops. Cover crop biomass, density, bounced-back percentages, and residue percentage cover will be determined. Tensiometers will be installed15-cm below the soil surface in each plot to collect leached water samples and soil samples will be collected from 0-15 cm depth. Samples will be analyzed for three allelochemicals (p-Hydroxybenzoxazinone, cyanamide, and polyethylene glycol) abundant in the CCs by using reversed-phase high-performance liquid chromatography. Weed biomass and density will be measured twice in the summer and soil seedbank will be determined using the germination assay technique for two years. Hemp biomass, fiber yield, sweetcorn cob yield, and grain quality are the crop parameters to be quantified. To involve farmers in the project, two demonstration trials will be established in the third year of the project in both locations. Feedback and farmer’s evaluation will be recorded. The project will prioritize technology adoption by using step-by-step approaches such as farmer and key obstacles identification, workshops, and consulting services. The outreach plan will have field days, web article publications, social media posts, two webinars, two peer-reviewed publications, regional and international conferences, video production, educational materials production, newsletters publications, and face-to-face training. Technology that makes rolled/crimped surfaces smooth and suppressive to weeds would be appealing to growers.

    Project objectives from proposal:

    The goal of this project is to demonstrate the ability of cover crops in suppressing weeds with different rolling/crimping approaches and promote it for no-till organic production.

    Three objectives were defined to achieve the goals:

    Research Obj.1: Compare the effect of three different roller crimping patterns on weed suppression.

    Research Obj. 2: Evaluate the interaction between rolling/crimping patterns and cover crop species by measuring the weed dynamics, sweetcorn (Zea mays) and fiber-hemp (Cannabis sativa) yield as high-value cash crops.

    Outreach Obj.1: Establish demonstration sites in two USDA plant hardiness zones to educate growers on rolling/crimping techniques in the Northeast agroecosystems.

    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.