Reducing plastic mulch use by expanding adoption of cover-crop-based no-till systems for vegetable producers

Reducing plastic mulch use by expanding adoption of cover-crop-based no-till systems for vegetable producers

Summary

To meet our project goals of informing at least 3000 growers about reducing plastic mulch use through no-till cover crops, Rodale Institute (RI) researchers successfully delivered extensive educational programming, completed the second year of RI research trials of tomatoes, and completed a first year of vegetable and fruit production research on 4 collaborating farms, and established 2011-2012 field trials on all 5 sites. Researchers disseminated information on cover crop-based no-till vegetable production to almost 4000 unique visitors through 3 project web articles and more than 350 farmers and educators visited the RI research and demonstration plots and nearly 150 received presentations on the practices at 4 educational events. Presentations focused on the effectiveness of the rye-vetch cover crop combination at both suppressing weeds and increasing soil nitrogen in tomato production while maintaining decent yield, while discussing differences in yield comparisons with black plastic relative to seasonal weather variations and the value of multi-year research to develop production practices that work in the long term.

Objectives/Performance Targets

Impact Objective 1 (Farmer Practices): By the end of this project, the Institute will have documentation that at least 25 regional farmers implemented this system on 10 percent of their collective vegetable production acreage (at least 20 acres), decreasing their input costs for that acreage by 90 percent, increasing their net income for that acreage by 50 percent, relative to their standard black plastic-based system. This performance objective will be assessed by follow-up phone and web-based surveys of farmer participants at project-related field days, extension-hosted events, and grower-oriented conference presentations.

1. At the July 2012 Field Day, “Showcasing the Value of Research In Organic Agriculture”, 8 of the 10 famers who returned surveys (80%) noted that they already used cover crops, and 9 of those 10 farmers (90%) indicated that the most valuable information they sought and found from the field day event regarded rolling cover crops for weed suppression and crop production. This year’s attendees were again pleased with the event over all (though, to counterbalance the 106° temperatures we had in 2011, this year we had a chilly 70° rainy day) and the primary suggestions for new topics related to RI’s livestock research, about which many people were excited and wanted to learn more (livestock topics ranked second to rolled cover crops/organic no-till in respondent interest). Several respondents noted that the sound system wasn’t always effective in helping everyone to hear, suggesting to break into smaller groups for training, and a couple requested better signage in the field. A few others reported a preference for the outdoor field tours in the afternoon over the power point presentations given in the morning. All this feedback is already being incorporated into the planning of RI’s July Field Day for 2013.

2. The project team also developed and carried out a project-specific field event (an evening field walk) entitled “No-Till Vegetable Production and Farm Food Safety GAP Mock Audit Twilight Field Walk”, on August 10th 2013. The event was held at project collaborator James Weaver’s Meadow View Farm, and carried out in collaboration with Penn State Extension. The evening attracted 16 attendees that first spent 45 minutes in the field touring James’ project plots of tomatoes and cabbage, and then took a tour of James’ packing facility with a GAP auditor to discuss steps that growers can take to improve food safety and marketability. The evening events and information were very well received and even led to coverage of the project in the local Reading Eagle newspaper. Survey feedback was positive, indicating that, though many already used cover crops, the farmer participants (who managed over 100 local acres) had learned new practices for both production and packing and planned to integrate them into their existing operations.

3. In February 2012, RI research staff hosted its second annual project collaborator meeting to interact directly with the 4 collaborating project farmers (John and Aimee Good, Doug and Elizabeth Randolph, Mike Baki, and James Weaver) on work plans for the 2012 season. The meeting provided a wonderful platform for everyone to come together, discuss what had worked and what hadn’t worked from the previous season, and make plans and adjustments for the coming year. Christine reported results that had been tabulated from the previous season by that point and made plans with the farmers to adjust the weeding schedule for the coming season, allowing the farmers to weed much sooner and to track their time spent on that effort. While the rolled cover crops hadn’t worked perfectly for all the farmers in that year, they all felt very positive about the system’s potential and were excited to try it again for another season.

4. Christine and Lindsey (the 2012 project technician) continued to work with the 4 collaborating farmers throughout the year to plant their cash crops, collect data, and wrap up at the end of the 2012 season. The Goods and the Randolphs grew acorn squash, while Mike Baki grew tomatoes, watermelon and summer squash, and James Weaver grew tomatoes and cabbages, and the area managed at all four farms totaled about 6 acres. Summer data collection included yields, soil samples for C/N analysis, soil microbiology, soil temperatures, and weed biomass. At the time of reporting, yield data is still being collected from the farmers and plans are being made convene a project wrap up meeting with them in February 2013.

Impact Objective 2 (Farmer Awareness): By the end of this project, the Institute will have documentation that at least 3000 farmers became informed about the cover crop mulch system of vegetable production, as documented by:

1. Attendance / participant surveys at RI field days,

A. One hundred eight people attended RI’s July 2012 Field Day, “Showcasing the Value of Research in Organic Production,” where the no-till vegetable trial was showcased alongside other RI projects. Attendees viewed a presentation about the project including the benefits of cover crops, had a tour of the trial, and responded to a survey. At this Field Day, only 16 of the 108 participants completed their surveys for a 15% response rate, due in part to the fact that a group of over 40 farmers from Canada had promised to return their surveys after they had returned home, but then failed to do so. Also, because of the poor weather that day, the afternoon tour ended on foot, rather than on the wagon, eliminating our primary venue for collecting end-of-day surveys and thus creating the poor response rate. Of the respondents, almost two-thirds were farmers (10), and most of the rest were extension agents and educators (6), working collectively with an estimated total of 600 farmers and land owners each year. Ninety three percent of the farmers noted that they had learned about a new production practice, and almost all noted that the primary new practice they were interested in was no-till rolling of cover crops for production of vegetables and soybeans (new livestock management systems were the other big area of interest).

B. Project presentations at RI’s June 8th field event hosted for PA Women in Agriculture (PA-WAgN), entitled “Annual Tour of Rodale Institute: What’s Happening on the Farm reached over 40 participants, and field tours provided as part of custom group tours throughout the season reached over 600 more visitors of all ages, ranging from elementary and home-school groups to college students to farmer-extension groups.

2. Attendance / participant surveys at grower-oriented conference presentations.

A. Sixteen farmers and other interested parties attended Rodale Institute’s “No-Till Vegetable Production and Farm Food Safety GAP Mock Audit Twilight Field Walk”, on Friday, August 10th, 2013. The event was held at James Weaver’s Meadow View Farm, whose 40+-acre mixed vegetable/nursery/grain farm is located about 5 miles southwest of the Rodale site in Bowers, PA. Participants toured James’ project production field, as well as his packing operation, and discussed current project data with RI’s staff. Almost all the survey respondents noted that they were currently growing cover crops and interested to try incorporating them more fully into their vegetable systems using the cover crop roller.

B. Over 60 farmers, researchers and extension agents received information on project production methods and results via Christine Ziegler’s presentation “Impacts of Plastic and Cover Crop Mulches on Weeds, Soil Quality, Yields, and Season Length for Tomatoes” at the University of Minnesota’s “Extending the Growing Season” Workshop held in April at their Southwest Research and Outreach Center in Lamberton, MN. Verbal feedback from the presentation was uniformly positive, with many questions about different kinds of cover crops that can be used in different regions of the country, and timing of cover crop termination and planting.

3. Independent page views of website articles.

A. “Cover Crops Go Round Three With Black Plastic,” an article posted on our website in June 2012, described the changes we made to our trial through the first half of 2012, and the details of how the work was carried out in the field. This posting had 1621 unique views with an average view-time of 4:05 minutes. (This article is available at http://www.rodaleinstitute.org/20120622_cover-crops-go-round-three-with-black-plastic. (For reference, average view times for web pages, nationally, are approximately 1 minute.)

B. An article entitled “Final Year of Field Research on Alternatives to Black Plastic” was posted in November 2012, detailing more findings from the 2011 season and preliminary data fro 2012. The page had 520 unique page-views with an average of 3:30 minutes spent on page. (This article can be viewed at: http://www.rodaleinstitute.org/20121116_final-year-of-field-research-on-alternatives-to-black-plastic .)

4. Responses to surveys posted in the sidebars of website articles.

A web survey was sent via email to all participants of RI’s 2010 and 2011 field days. Seventeen recipients viewed the survey and 7 completed it, for a view rate of 20% and return rate of 8%. Two of the seven respondents were farmers (representing 130 acres of vegetables, grains, and fruit), one of whom already used cover crops and another who added 20 acres of cover crops as a result of attending the field day. Neither had tried rolling cover crops yet but one was interested in learning more about the equipment, and both felt that the cover crops were a success and were improving their soil organic matter. Two other respondents worked with farmers – one works with 5-6 farmers, and one works with “many”, and the latter is recommending cover crops to his clients. A fifth respondent who didn’t identify as farmer or educator noted that the event increased her understanding of cover crops “enormously” and that she “helped to organize a cover crop conference in Oct 2011 at Princeton University” and “As a result at least one agribusiness company has begun to develop more cover crop options for their farmer’s rotations and we worked with the National Corn Growers Association to collect cover crop data during their survey for the national conference.” Overall, the feedback to the field events was very positive – all noted that they appreciated the information presented and the event as a whole, and wanted to attend again in the future. The same survey will be sent out to attendees of RI’s 2012 Field Day in early January, to capture feedback from that group.

5. Purchases of printed Production Manual.

With 2012 data collected and now being analyzed, dedicated work on the production manual will begin in earnest in January 2013, drawing from reports and presentations given over the previous three years, and taking guidance from farmer and extension feedback as to what issues are of most interest and concern to those target audiences.

6. Responses to survey linked to production manual download.
These data will be collected once the production manual is complete in 2013.

Impact Objective 3 (Professional Development): 8 regional extension agents will each host or schedule to host at least 1 event, collectively reaching 400 farmers, that includes information on cover crop use and no-till termination for vegetable production.
Collaborating extension agent Tianna DuPont will deliver model presentations at the field days, and RI researchers will quantify extension agent adoption through follow-up phone surveys of extension agent field day attendees.

A. With data from the 2012 Rodale Institute trial starting to be summarized and clarified, we are updating information to provide extension agents regarding growth of vegetables with cover crop mulches. Thus far, 2012 data appears to corroborate trial outcomes from 2010, suggesting that rye-vetch mixtures are superior to either vetch alone or rye alone for weed suppression and nitrogen inputs, with yields comparable to black plastic systems. Data from 2011 pointed to somewhat different conclusions, in that the rye/vetch combination was still the best of the three covers used, but yields were highest in the black plastic treatments, likely due to 2011’s unusual weather patterns. As the data are fully compiled and finalize, they will be outreached at grower and research conferences in the spring of 2013, as well as through the outreach publications and web articles outlined for the project.

B. Collaborating local extension agents carried out over two dozen courses in the SE region of PA in 2012. In addition to vegetable production courses that included project information on rolled cover crops and organic no-till, course topics included Beekeeping, Potato Production, Soils, Livestock Grazing and Pasture Management, Backyard Poultry Production, Access to Land, Capital and Equipment for Farm Start-ups, Sheep and Goat Management, GAP Food Safety and Handling, and Novice Farmer Study Circles. These courses were attended by almost 500 farmers and extension agents, and another group of these courses is set for 2013.

Impact Objective 4 (Researcher/Ag Professional Awareness): By the end of this project, the Institute will have documentation that at least 500 horticultural research scientists and extension agents became informed about the cover crop mulch system of vegetable production.
This Impact Objective has not yet been addressed, but will be assessed in Year 3 of the project.

Accomplishments/Milestones

Milestone 1:

(Completed in 2010) More than 1,500 people viewed the introductory project article for an average of almost 4 minutes. Most viewers who responded to the survey posted with the article indicated an interest in finding alternatives to black plastic and a need for more information (n=10). Some had tried conservative experimentation with cover crops already, and were eager to find plastic alternatives, but were concerned about weed-control and lack of equipment. Next year, we plan to boost survey responses by increasing survey visibility, by linking the survey to the RI main page, and by contacting farmers directly by email and phone.

Milestone 2:

Technicians installed 3 temperature data loggers in each RI plot (n=88) and in all the farmer collaborator’s (FC’s) plots in early June 2012 (n=54). Ibuttons were successfully removed in October to collect soil temperature readings throughout the season. Average full-season soil temperatures (June through October) showed no significant differences at the RI site in the nine different treatments (as in 2010 and 2011), ranging in from 59 F in the rolled vetch plots in early June to 98 F in the black plastic rye plots in early July. However, when daily soil temperature highs and lows were separated by month, distinct differences emerged among the treatments (Figure 1), with the rye and rye/vetch black plastic plots showing the highest daytime temperatures in June and July (around 82 F) and the rye rolled and mowed plots showing the lowest daytime temperature in July (around 72 F), a difference of 10 degrees. The month of June showed the greatest differences between daytime and nighttime temperatures for all the treatments, with a change of at least 10 degrees between the time readings. The swing between daytime and nighttime temperatures decreased over the course of the growing season, as did the daytime temperature differences between the treatments, particularly in August, when daytime soil temperatures showed the smallest difference between the treatments.

Figure 1 – 2012 RI Soil Temperature Data

Soil temperatures at the FC plots are still being analyzed and will be reported by the end of January.

Soil samples were taken at different points throughout the growing season at the RI site to determine gravimetric soil moisture. Data for April and June have been tabulated (Figure 2) and analysis of the later season readings is on-going. For these two months, average percent soil moisture ranged from 24.2% for rye/vetch in black plastic to 30.6% for mowed vetch, a range similar to those seen in the last two seasons. Though the treatments including vetch appear to hold more moisture in April, differences among the treatments become negligible by June (to be confirmed by statistical analysis in January). This growing season brought fairly consistent rainfall, and as such, coming analysis of the remaining soil moisture data should clarify whether and how the treatments impacted soil moisture later in the season, given “normal” moisture conditions. (Soil moisture was not measured at the FC locations.)

Figure 2 – Soil Moisture at the RI Site for April and June

Cover crop biomass was collected for analysis of biomass production, percent N, and percent C. Once again, vetch biomass production at RI was even greater this year than last year, reaching nearly 5000 lb/ac (compared to 4000 lb/ac in 2011 and 2200 lb/ac in 2010). Rye biomass reached 10,000 lb/ac, on par with 2011 (and much higher than the 4700 lb/ac in 2010), but the rye/vetch treatments produced less biomass, reaching a maximum of about 7800 lb/ac compared to 11,500 lb/ac in 2011 (Figure 3). What is also interesting to note is that the rye biomass nearly doubled from the time of plow termination for black plastic (April 14th) to the time of rolling and mowing (June 5th), while the rye/vetch biomass did not increase as much over that time period. The vetch biomass also did not increase much between the plowing and rolling/mowing dates this year, but this is due to the fact that plowing and rolling/mowing for this treatment happened only 3 weeks apart (May 22nd to June 5th). Unlike last year, which brought an extremely wet spring, April and May were relatively dry in this area in 2012, which may have hindered vetch growth as much as the excess moisture in 2011.

Figure 3 – Cover Crop Biomass and C:N Ratio (x100) at the RI Site

Cover crop biomass at the FC sites, consisting primarily of the rye/vetch mix, ranged from 4900 lb/ac on April 27th (plow/black plastic at Baki’s) to 12,300 lb/ac on June 1st (rolled at Randolph’s), a range very similar to 2012. Again, Baki’s cover crops showed excellent growth between the plowed and rolled terminations dates (late April to late May) but growth at the Good’s plot (which is located at the RI site) was quite minimal over the same time period. Weaver’s cover crop biomass also only increased from 7800 lb/ac to 10,000 lb/ac from April 12th to May 30th, indicating that a dry spring may have slowed cover crop growth a bit in the area near Rodale Institute.

Nitrogen (N) concentrations were greatest in the vetch and mixed rye/vetch treatments (200 lb N/acre) and lowest in the rye treatments (70 lb N/acre), which is consistent with what the rye/vetch and rye cover crops produced last year (the vetch alone produced around 70 lb/ac more N in 2012 than in 2011). However, again, the vetch and rye/vetch cover crops showed little or no increase in N conten between mid-April and early June, even though the biomass increased. Carbon (C) inputs ranged from 2200 lb/ac for the vetch (at all termination dates) to 4500 lb/ac for the rye/vetch mix at the roll/mow termination date, which is right in line with data from 2011.

Figure 4 – Cover Crop Percent Carbon and Nitrogen at the RI Site

At the FC plots, N concentrations were unusually low this year, ranging from 28 lb/ac in Baki’s plowed/black plastic plots that were terminated on April 27th to 134 lb/ac for Randolph’s plots that were rolled on June 1st. C inputs, however, were excellent in these plots, ranging from 2200 lb/ac to 5500 lb/ac on these same plots, which was exactly the same as 2012. We are not certain how to explain the low N concentration in these cover crops, but it is possible that the vetch simply didn’t grow as well over the 2012 winter as it did in 2011, even though the rye grew normally.

Milestone 3:

After adjusting our weed data collection in 2011 to only assess weed biomass, based on the determination that the weed species data was not of sufficient value, we then adjusted our weed data collection again in 2012. In this year, we only collected weed biomass at 4 weeks after planting, and after that point, we instead measured the amount of time that was required to control the weeds in the plots. Weed biomass was assessed at 4 weeks, both at RI and the FC locations.
At 4 weeks after planting at RI, the rolled and mowed treatments showed similar weed suppression, and in some cases showed statistically similar weed suppression to that of the black plastic (the black plastic serves as a control in this portion of the research, and the weeds collected were those that fell beyond the reach of the plastic, between rows). The mowed rye showed the greatest weed suppression of the non-plastic treatments, amassing less than 4000 kg/ha of weed biomass, while the mowed rye/vetch amassed almost 2000 kg/ha of weeds, and the mowed vetch and mowed rye allowed over 6000 kg/ha of weeds at that date (Figure 5). Despite the fact that the 2012 RI plots produced just as much cover crop biomass as the 2011 plots, they appeared to be less effective at deterring weed growth. In 2011 data, after 4 weeks, the rolled rye/vetch treatments had only 500 lb/ac of weeds, the rolled vetch treatments had 2100 lb/ac of weeds, and the mowed vetch and rye had about 3800 lb/ac of weeds. It is possible that the steady supply of moisture throughout the 2012 growing season allowed for greater weed growth, relative to the dry 2011 mid-summer season.

Figure 5 – Cover Crop Biomass, correlated with 4-Week Weed Biomass at the RI Site

After the 4-week weed biomass cut, weeds at the RI site were managed with an in-row hand weeding, followed by occasional mowing between the plots. Weed management time data is still being tabulated for the RI site and will be complete by the end of January.

Four-week weed pressure at the FC plots was extremely low, ranging from 78 lb/ac in the Good’s plowed fields to 1450 lb/ac in Weaver’s rolled fields (most of the FC plots had weed pressure of less than 500 lb/ac). These weed pressure data are lower than those of 2011, where data ranged between 900-1500 lb/ac, with a high of 3000 lb/ac at Weaver’s. Time and methods for weed control after 4 weeks at the FC sites is still being tabulated. The highest pressure in Weaver’s rolled plots (though it still isn’t very high) may again be due to the fact that he planted on raised beds and used the project’s new raised-bed roller to terminate the cover crop. The roller again appeared to give good kill of the cover crop, and the cover crop biomass was comparable with the other sites, but it is possible that the orientation of the raised-bed roller’s angled drums may have moved the crushed cover crop mat in a way that allowed for weed emergence. Since these data are similar between 2011 and 2012, they suggest that the raised bed roller may need some adjustments before being recommended for large scale use.

Milestone 4:

Total tomato yield was collected and weighed twice or three times weekly at the RI site from August 13th until September 6th. The harvest season started at a reasonable date, due to the normal weather patterns, but ended very early due to an outbreak of Late Blight that struck in late August (only at the RI site). Both total and marketable yields were assessed, and as in previous years, to avoid flooding the market and displacing local tomato farmers, project tomatoes were donated to the Berks County Food Bank.

Because of the blight, marketable yields ranged from 2500 lb/ac in the mowed vetch treatment (total yield for that treatment was 18,000 lb/ac) to 21,000 lb/ac (50,000 lb/ac total yield) in the rye black plastic plots, totaling over 3000 lbs of tomatoes picked throughout the season (Figure 6). (To compare, in 2011 total yields ranged from 15,000 lbs/acre in the mowed rye treatment up to 84,000 lbs/acre in the rye-vetch black plastic treatment, and a total of around 6500 lbs of tomatoes were picked over the season.) These yields are lower than the Pennsylvania 10-year commercial average of 10,500 to 22,000 lbs/acre due to the blight and the shortened picking season. While the black plastic plots generally yielded statistically more total tomatoes than the rolled or mowed treatments for all cover crop types, there were no statistical differences in marketable yields among the nine treatments. Though these data are rather different from those of 2010 and 2011, due to the impact of the late blight, they suggest, in their raw form, that the rye/vetch rolled and mowed treatments can produce comparable yields to those of the black plastic, as was seen in 2010. Statistical comparison of all three years’ data is on-going and should be complete by the end of January.

Figure 6 – Total and Marketable Tomato Yields at the RI Site

Harvest data from the FC’s is still being tabulated, but raw 2012 data on acorn squash from the Good’s and Randolph’s showed that yields in the rolled plots were higher than in their standard treatments. These data analyses will also be completed by late January.

Milestones 5, 11, 14, 15, and 16:

The July 2012 Field Day, “Showcasing the Value of Research in Organic Production,” hosted at Rodale Institute, educated a total of 108 participants on cover crop use, supplemental weed control practices, and no-till practices. In addition to the July field day, the second project farmer field day, “No-Till Vegetable Production and Farm Food Safety GAP Mock Audit Twilight Field Walk”, gave 16 participants an up-close and focused opportunity to review the trial on an FC’s farm, learn about the FC’s experiences in implementing the production practices, and receive up-to-date trial data. A third outreach presentation entitled “Impacts of Plastic and Cover Crop Mulches on Weeds, Soil Quality, Yields, and Season Length for Tomatoes” was given at the University of Minnesota’s “Extending the Growing Season” Workshop held in April at their Southwest Research and Outreach Center in Lamberton, MN. Survey data and participant feedback from these events, as well as data on project articles presented on RI’s website, are listed in the “Objectives/Performance Targets” portion of this report.

Milestone 6:

As in previous years, RI staff worked with the four collaborating farmers throughout the growing season to lay out field treatments; assist with cover crop incorporation, rolling, and crop planting; take cover crop and weed biomass cuts; deliver and plant cover crop seed; sample soil for percent moisture, rocks and fines, and active organic carbon; and answer any questions the farmers had about the project or the work involved. All the farmers were very willing and helpful collaborators throughout the season and a delight to work with. The winter planning meeting provided a good opportunity for all to see each other again, discuss ideas and plans as a group, and make sensible changes for the coming growing season. While the farmers’ 2011 experiences with the rolled cover crop treatments were mixed, ranging from full success at the Good’s and Randolph’s to fairly serious failure at Baki’s and Weaver’s, all four farmers were excited to try the treatments again in 2012, making adjustments for weed pressure (allowing weeding after 4 weeks), and all carried through admirably.

Milestone 7:

On-farm and RI trial soil samples were collected in September and October and are currently being processed to determine percent moisture, and percent rocks and fines. Data for active organic carbon is also currently being processed at Cornell. Samples of cover crop biomass were analyzed on-site this year for carbon and nitrogen concentration and active carbon data for 2011 and 2012 will be reported as soon as it is tabulated and available, by late February 2013.

Milestones 8, 9, 12 and 13:

The FC Winter Workshop in late February 2012 brought the stakeholders together to review the article that had been posted on the website in January and discuss work plans for the coming season. FC costs and savings calculations will be made in winter 2013 to encompass both full field seasons of the project.

Milestone 10:

The on-line field day participant survey was sent to participants of the 2010 and 2011 events in mid-2012, and results from this survey are outlined in the “Objectives/Performance Targets” portion of this report. Plans are in place to send the survey to participants of the 2012 Field Day in early January, and results from that mailing will be tabulated in late February 2013. If data from these outreach mechanisms are not adequate to fulfill our interests and information needs, then plans are being made to commence a phone survey of a cross-section of event participants in order to glean more tangible and quantifiable data on the adoption and use of rolled cover crops for vegetable production.

Milestones 17, 18, and 19:

Due to the time needed to finish processing and analyzing the 2012 data and correlate it with data from the previous years, work on the production manual, peer-reviewed manuscript and final project articles will begin in earnest in January 2013. The revised timeline for these deliverables will be May 2013 for a review draft of the production manual and a review draft of the manuscript complete by June 2013, with a final web article posted by July 2013 to summarize final result and announce the production manual.

• Figures
• Milestones Table 2012 Annual Report

Impacts and Contributions/Outcomes

The major accomplishments of the third year of project work have been the collection of field data at RI, the continued development of relationships with the farmer collaborators, and successful outreach through a variety of field days, presentations, and web materials. With the end of field operations for this project, this final year of work will summarize all the project data into the Production Manual and manuscript, making the data and discoveries from this project work available to as wide an audience as possible.

Collaborators: