Source: LOUISIANA STATE UNIVERSITY submitted to
BUILDING GEO-SPATIAL DATABASES TO IMPROVE THE PRECISION OF COVER CROPS AS AN IWM TOOL
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
1024321
Grant No.
2020-70006-33020
Project No.
LAB94507
Proposal No.
2020-07471
Multistate No.
(N/A)
Program Code
ARDP
Project Start Date
Sep 1, 2020
Project End Date
Aug 31, 2023
Grant Year
2020
Project Director
Miller, D.
Recipient Organization
LOUISIANA STATE UNIVERSITY
202 HIMES HALL
BATON ROUGE,LA 70803-0100
Performing Department
Schl of Plant, Env & Soil Sci
Non Technical Summary
The continuing rise in the development of herbicide-resistant weeds drives the need for integrated weed management (IWM) tactics to preserve crop yields and make more judicious use of herbicides. The use of cover crops is one tool in the IWM arsenal. However, IWM in general and the use of cover crops specifically have not been widely adopted, largely because the complexity of interactions among cover crops, climate, soil, management, and weeds is daunting and makes IWM a time-consuming task. We propose on-farm research at many sites across a wide latitudinal gradient to define and cover crop management by environment impacts on weeds to improve the precision of cover crops as an IWM tool by creating literal management IWM decision tools that reduce complexity for farmers. In doing so we aim to increase the adoption of cover crops as an IWM practice and to improve the use of IWM in general by making it easier for farmers to target (and thus reduce) herbicide applications while realizing ancillary benefits of cover crops (e.g. reduced soil erosion, nutrient loss, etc.). This project supports the ultimate CPPM goal of sustainable food security through the improvement of IWM practices (i.e. inclusion of cover crops in cropping systems to manage weeds) that increases IPM adoption (i.e. use of non-herbicide methods of weed control) and reduces environmental and human health risks (i.e. via decreased herbicide application) while supporting farmer profitability.
Animal Health Component
0%
Research Effort Categories
Basic
20%
Applied
80%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2132300114025%
2130199107015%
1022140106025%
2167210114025%
2162300303010%
Goals / Objectives
Our objectives directly relate to the goals of the National IPM Roadmap by investigating local and regional climatic effects on the use of CCs as an IWM tactic (Obj. 1), developing CCs as a row crop management tactic to prevent/minimize weed (i.e. pest) damage (Obj. 1 & 2), developing CCs as a low-risk suppression tactic that is efficacious and cost-effective (Obj. 2), expanding web-based resources for IWM systems (Obj. 1-3), and evaluating and demonstrating the efficacy of precision agriculture IWM tactics deployed within or across growing seasons and landscapes (Obj. 1 & 2).Objectives:1. Elucidate the interactions between climate, soil, and CC management on cover crop performance and resulting weed suppression in an existing on-farm network across the mid-Atlantic and southern US while expanding the network to include weed-focused sites in new states (research objective).2. Assess the impact of spatial heterogeneity on weed suppressive potential of CCs using image analysis-based predictive models (research objective).3. Conduct IWM extension outreach and training to promote CC adoption across the study region (mid-Atlantic and southern US) and beyond (extension objective).
Project Methods
Objective 1. Demonstrate the interaction between climate, soil, and CC management on CC performance and resulting weed suppression in an existing on-farm network across the mid-Atlantic and southern US and through expansion of the network into new states with weed-focused sites.Demonstrations on weed suppression by CCs will be conducted using on-farm and on-station trials in soybean, corn, and cotton fields that have strips with and without CCs. A minimum of two blocks (i.e. replications) will be established in on-farm trials (more if resources permit) and four in on-station trials.The cropping system will be chosen based on a preferred system in each region and will begin with a soybean phase rotating into the subsequent crop. CCs will be established in late fall. No-CC strips will be established when planting by not planting an area or killing CCs with herbicides two weeks after emergence.Management practices as well as intrinsic factors will be recorded and included in the overall data set. CC biomass will be sampled from each plot (from five random 1 m2 quadrats/plot) just prior to termination and will also be analyzed for C:N ratio. Weed emergence will be monitored by counting weed species density (three most prevalent species) in permanently established 1 m2 quadrats (five quadrats/plot); seedling emergence will be counted at biweekly intervals until crop canopy closure and a final assessment at harvest. At harvest, species-wise weed density, ground coverage, biomass, and seed production (three most common species) will be measured in the quadrats. Weed biomass will be quantified by clipping weeds at the soil surface and hand-separated to quantify individual species, and oven-dried and weighed. Weed seed will be separated and quantified.Objective 2. Assess the impact of spatial heterogeneity on weed suppressive potential of cover crops using image analysis-based predictive models.Image and ground truth data collection. Digital images will be collected using a low-cost overhead imaging system mounted with a high-resolution RGB camera, which will be compared with ground truth data collected at the same time. The size of the experimental unit will be 1 m2, which will be replicated 5 times within each plot. First, the influence of CC live biomass on the suppression of winter annual weeds will be assessed by capturing overhead images during cover crop growth period at monthly intervals. Further, starting at CC termination, pictures will be taken every two weeks until crop canopy closure. Ground truth measurements include visual counts of weed density, ground cover rating (%), and aboveground biomass assessment, which will be carried out immediately following image acquisition in every experimental unit at each observation timing.Image analysis-model training. Following image acquisition, two different methods will be employed to analyze the acquired images depending on the level of complexity of the species in the mixture, which is expected to vary across environments. The images will be pre-assessed for quality and pre-processing requirements. The approved images will be standardized to eliminate the variations resulting from illumination and resolution differences and stored in a web database for multi-user processing. Approximately 100 images will be acquired outside of the treatment units within each study site at different plant growth stages to create trainable synthetic images using the image synthesis procedure.Plant segments will then be randomly affixed to the soil texture at random density, generating composite images and ground truth annotations. Different artificial neural network structures will be tested for semantic segmentation for best performance. In addition to synthesized images, true annotated images will be added to the training dataset to improve segmentation accuracy. For this purpose, approximately 1000 images will be collected outside of the treatment unit encompassing different plant growth stages and conditions within each experimental field. The trained model will then be used to classify pixels in the image under consideration for further assessment. It is expected that the model will be robust across multiple environments.Image analysis- model validation. The images acquired from within the experimental units (i.e. 1 m2 quadrats within each plot), will be used to validate the trained model in comparison with the ground truth data collected alongside. Both the object-based method and the neural network-based method developed on the training set will be validated on the experimental dataset. The validation process will also serve to assess the impact of cover crops on weed population dynamics.Assessment of weed suppression potential. Weed detection and classification results from image analysis will be further post-processed to generate information for weed density, canopy cover, and biomass. The canopy masks per species will be assessed against biomass to develop quantitative models that could be used to estimate biomass based on image-derived information, as biomass and canopy pixel coverage areas are shown to have non-linear relationships.Objective 3. Conduct IWM extension outreach and training as part of the implementation of weeds research in an existing on-farm network across the mid-Atlantic and southern US.On-farm research will serve as demonstration to other growers in a region and an opportunity for collaborative co-learning with researchers. The in- field sensor technologies employed by the existing on-farm research project, which allow farmers to view real-time field data (e.g., soil moisture in +/- CC plots), provide a novel means of engaging farmers as collaborators rather than passive recipients of information. Farmers participating in the proposed weeds research module will observe the impact of CCs and CC management decisions on weed emergence and growth and cash crop yields. Farmers will link observations with hard data, improve their decision-making based on these observations.

Progress 09/01/20 to 08/31/23

Outputs
Target Audience:The target audiences for this project include cover crop, soybean, corn, and cotton industry stakeholders and research commodity groups. Findings are alsoof interest to the broiader agricultural scientists, ecologists, modelers, and precision ag scientists who are focused on understanding the interaction between integrated weed management and crop production. Changes/Problems:The Advisory Board for this project was changed to an Advisory Board for the larger GROW (https://growiwm.org/) network that is supported in part by this funding. The Advisory Board met on Feb 23, 2023 and Oct 18, 2023. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Preliminary results have also been disseminated through traditional extension presentations and field days, noted under accomplishments in Objective 3. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Objective 1. Harvest and data entered into shared Google Drive. Digital imagery (Videos) was uploaded through the PSA tablet system, as per the protocol. Weed density data was entered into shared Google Drive. Objective 3. Extension outreach. Co-PI Flessner delivered the following extension presentations, which in part included information from Objectives 1 and 2 of this project: No. Date Program Location Title/contribution Audience No. 1 1/10/2023 Growmark Crop School Roanoke, VA Cover crops, weeds, and herbicides 24 2 1/10/2023 Tri-County Crops Meeting Carson, VA Cover crops, weeds, and herbicides 35 3 1/10/2023 4 Rivers Ag Conference Quinton, VA Cover crops, weeds, and herbicides 20 4 1/11/2023 Five County Ag Conference Doswell, VA Cover crops, weeds, and herbicides 125 5 1/12/2023 Northern Neck Crops Warsaw, VA Cover crops, weeds, and herbicides 35 6 1/12/2023 Middle Peninsula Crops Conference Saluda, VA Cover crops, weeds, and herbicides 20 7 1/18/2023 Virginia Crop Production Association Crops Summit Midlothian, VA Cover crops, weeds, and herbicides 120 8 2/21/2023 Professional Crop Services Meeting: Agronomic Crops Section Weyers Cave, VA Cover crops, weeds, and herbicides 65 9 2/23/2023 124th Annual Virginia Cotton Meeting Franklin, VA Cover crops, weeds, and herbicides 175 10 2/23/2023 124th Annual Virginia Cotton Meeting Franklin, VA Cover crop panel member 175 11 3/8/2023 Innovative Farmer Roundtable Stony Creek, VA Cover crops and weed management discussion 24 12 3/31/2023 Tidewater Soil Fertility and Cover Crop Field Day Holland, VA Cover crops for weed Management 65 Co-PI Flessner delivered the following extension workshops or field days, which in part included information from Objectives 1 and 2 of this project: No. Date Program Location Title/contribution Audience No. 1 3/7/2023 Purposeful Cover Cropping Halifax, VA Managing Cover Crops for Meet Your Goals 34 2 3/15/2023 Purposeful Cover Cropping Unionville, VA Managing Cover Crops for Meet Your Goals 24 3 3/16/2023 Purposeful Cover Cropping Singers Glen, VA Managing Cover Crops for Meet Your Goals 32 4 8/3/2023 Virginia Ag Expo Virginia Beach, VA Cover crops for Palmer amaranth and common ragweed suppression 50 5 8/11/2023 Central Virginia Ag Expo Hat Creek, VA Cover crops for Palmer amaranth and common ragweed suppression 75 The following were posted to the GROW Website, which were partially supported by this project: https://growiwm.org/measuring-cover-crops-for-weed-control/ https://growiwm.org/the-ag-image-repository-a-first-step-in-accessible-precision-ag/ https://growiwm.org/how-a-national-image-repository-can-transform-agriculture/

Publications


    Progress 09/01/21 to 08/31/22

    Outputs
    Target Audience:The key target audiences for this project include cover crop, soybean, corn, and cotton industry stakeholders and research commodity groups. Our findings will also be of interest to the broader agricultural scientists, ecologists, modelers, and precisionagricultural scientists who are focused on understanding the interaction between integrated weed management and. Our targetaudiences will be informed of the research updates through production of timely reports, bulletins and presentations in stakeholder meetings and scientific conferences. Changes/Problems:The Advisory Board has yet to be established, however, invitations are currently being distributed with the goal of the first meeting in late 2022 or early 2023. What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?First year results were presented to an audience of academics and industry members at the Southern Weed Science Society annual meeting in early 2022. Preliminary results have also been disseminated through traditional extension presentations and field days, noted under accomplishments. What do you plan to do during the next reporting period to accomplish the goals? Harvest cash crops (obj. 1) Final statistical analyses of CC impact on weeds (Obj. 1) Incorporate modeling results into IWM tool (Obj. 2) Finalize extension materials (Obj. 3) Train-the-trainer events including at Northeastern Cover Crops Council meeting (Obj. 3) Promote extension materials (Obj. 3)

    Impacts
    What was accomplished under these goals? Objective 1. Year 2 data collection has been completed except for harvest (yield) data. Data has been being entered. Objective 2. Digital imagery has been collected and is being compiled for processing. The imagery will be processed for year 2 this winter. Objective 3. Extension outreach. Co-PI Flessner delivered 5 extension presentations reaching a total audience of 230 that included using cover crops for weed management, supported by findings to date from this project. Co-PI Mark VanGessel and Eugene Law delivered presentations at Delaware and Maryland Weed Management Field Days on June 29th that included this project with a total audience of about 60. Co-Pi Muthu Bagavathainnan presented findings at the Texas Plant Protection Association Meeting, and were discussed to growers in two county extension meetings and a turn-row meeting in Southeast Texas.

    Publications

    • Type: Conference Papers and Presentations Status: Awaiting Publication Year Published: 2022 Citation: Abstract: Chu, S.A., G. Labiche, & Lazaro, L.M. 2022. Suppression of Weeds Via Cover Crops in Soybean. Proc. South. Weed Sci. Soc. 75:30.


    Progress 09/01/20 to 08/31/21

    Outputs
    Target Audience:The key target audiences for this project include cover crop, soybean, corn, and cotton industry stakeholders and research commodity groups. Our findings will also be of interest to the broader agricultural scientists, ecologists, modelers, and precision agricultural scientists who are focused on understanding the interaction between integrated weed management and. Our target audiences will be informed of the research updates through production of timely reports, bulletins and presentations in stakeholder meetings and scientific conferences. However, the project was just initated one month ago, so there is nothing to report. Changes/Problems:The methodology for objective 2 has been altered, but the end goal has not. The changes in methodology has resulted in changes to technology and ease of the user. What opportunities for training and professional development has the project provided?Undergraduate and graduate students have taken or are curently taking the necessary training for this project. How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals?Objective 1. Demonstrate the interaction between climate, soil, and CC management on CC performance and resulting weed suppression in an existing on-farm network across the mid-Atlantic and southern US and through expansion of the network into new states with weed-focused sites. Demonstrations on weed suppression by CCs will be conducted using on-farm and on-station trials in soybean, corn, and cotton fields that have strips with and without CCs. A minimum of two blocks (i.e. replications) will be established in on-farm trials (more if resources permit) and four in on-station trials. The cropping system will be chosen based on a preferred system in each region and will begin with a soybean phase rotating into the subsequent crop. CCs will be established in late fall. No-CC strips will be established when planting by not planting an area or killing CCs with herbicides two weeks after emergence. Management practices as well as intrinsic factors will be recorded and included in the overall data set. CC biomass will be sampled from each plot (from five random 1 m2 quadrats/plot) just prior to termination and will also be analyzed for C:N ratio. Weed emergence will be monitored by counting weed species density (three most prevalent species) in permanently established 1 m2 quadrats (five quadrats/plot); seedling emergence will be counted at biweekly intervals until crop canopy closure and a final assessment at harvest. At harvest, species-wise weed density, ground coverage, biomass, and seed production (three most common species) will be measured in the quadrats. Weed biomass will be quantified by clipping weeds at the soil surface and hand-separated to quantify individual species, and oven-dried and weighed. Weed seed will be separated and quantified. Objective 2. Assess the impact of spatial heterogeneity on weed suppressive potential of cover crops using image analysis-based predictive models. Image and ground truth data collection. Digital images will be collected using a low-cost overhead imaging system mounted with a high-resolution RGB camera, which will be compared with ground truth data collected at the same time. The size of the experimental unit will be 1 m2, which will be replicated 5 times within each plot. First, the influence of CC live biomass on the suppression of winter annual weeds will be assessed by capturing overhead images during cover crop growth period at monthly intervals. Further, starting at CC termination, pictures will be taken every two weeks until crop canopy closure. Ground truth measurements include visual counts of weed density, ground cover rating (%), and aboveground biomass assessment, which will be carried out immediately following image acquisition in every experimental unit at each observation timing. Image analysis-model training. Following image acquisition, two different methods will be employed to analyze the acquired images depending on the level of complexity of the species in the mixture, which is expected to vary across environments. The images will be pre-assessed for quality and pre-processing requirements. The approved images will be standardized to eliminate the variations resulting from illumination and resolution differences and stored in a web database for multi-user processing. Approximately 100 images will be acquired outside of the treatment units within each study site at different plant growth stages to create trainable synthetic images using the image synthesis procedure. Plant segments will then be randomly affixed to the soil texture at random density, generating composite images and ground truth annotations. Different artificial neural network structures will be tested for semantic segmentation for best performance. In addition to synthesized images, true annotated images will be added to the training dataset to improve segmentation accuracy. For this purpose, approximately 1000 images will be collected outside of the treatment unit encompassing different plant growth stages and conditions within each experimental field. The trained model will then be used to classify pixels in the image under consideration for further assessment. It is expected that the model will be robust across multiple environments. Image analysis- model validation. The images acquired from within the experimental units (i.e. 1 m2 quadrats within each plot), will be used to validate the trained model in comparison with the ground truth data collected alongside. Both the object-based method and the neural network-based method developed on the training set will be validated on the experimental dataset. The validation process will also serve to assess the impact of cover crops on weed population dynamics. Assessment of weed suppression potential. Weed detection and classification results from image analysis will be further post-processed to generate information for weed density, canopy cover, and biomass. The canopy masks per species will be assessed against biomass to develop quantitative models that could be used to estimate biomass based on image-derived information, as biomass and canopy pixel coverage areas are shown to have non-linear relationships. Objective 3. Conduct IWM extension outreach and training as part of the implementation of weeds research in an existing on-farm network across the mid-Atlantic and southern US. On-farm research will serve as demonstration to other growers in a region and an opportunity for collaborative co-learning with researchers. The in- field sensor technologies employed by the existing on-farm research project, which allow farmers to view real-time field data (e.g., soil moisture in +/- CC plots), provide a novel means of engaging farmers as collaborators rather than passive recipients of information. Farmers participating in the proposed weeds research module will observe the impact of CCs and CC management decisions on weed emergence and growth and cash crop yields. Farmers will link observations with hard data, improve their decision-making based on these observations.

    Impacts
    What was accomplished under these goals? Objective 1. Year 1 data collection has been completed and data is being entered.Field locations for the on-farm and on-station trials have been initiated for year 2. Some locations have planted the cover crops. Objective2. Digital imagery has been collected and the methodology has been updated to reflect changes in technologies. The imagery will be processed for year 1 this winter. Objective 3. Extension outreach will begin this winter.

    Publications