Small-scale vegetable farmers who are interested in organic production are continually seeking cost-effective and practical management practices that conserve soil, reduce labor, and increase the profitability and sustainability of their livelihood. Preliminary results of a demonstration trial at Rodale Institute in 2016 showed that using no-till low input technology has the potential farming to conserve soil and sustain vegetable production. Quiet Creek Farm owners John and Aimee Good, grow organic produce for a 250 member CSA and are interested in cost effective management systems that reduce their dependence on frequent cultivations to conserve soil and ensure high yields. The Goods are partnering with Rodale Institute to compare side-by-side the impacts of using a low-input no-till system, a high-input no-till system and bareground (standard farmers’ practice) management systems. They are interested in gaining knowledge and experience in using a roller-crimper to determine the feasibility and effectiveness of no-till low-input technology for soil and weed management in an organic system. Similar treatments will be compared within existing field trials at Rodale Institute. In the Rodale trial, the low-input no-till system will be compared to high-input no-till and plasticulture (standard farmers’ practice) systems. In all trials, we will assess soil health, weed biomass and density, crop yield and feasiblity. Results will be shared with growers and interested clientele through Rodale’s Annual On-Farm Field Day, a web article, and presentations at grower conferences.
In United States, one of the responses to soil degradation has been the promotion of soil conserving tillage practices known as reduced-or no-till agriculture. While these new ways of farming represent new opportunities, no-till transplanters, seed drills, and cover crop termination equipment require a high initial investment and can be considered too expensive for beginner and limited resource farmers. Thus, discouraging them from adopting no-till practices that promote soil conservation. Dependence on cultivation to control weeds may be more feasible for new farmers that are risk adverse and thus shy away from adopting no-till farming to avoid incurring significant debt.
In discussions with Pennsylvania and northeast farmers at the 2016 Mid-Atlantic Vegetable and Fruit Association conferences, small-scale and beginner vegetable crop farmers expressed interest in finding affordable low-input management system to accelerate the adoption of reduced or no-till system.
In spring 2016, Dr. Zinati demonstrated in a non-replicated design a low-input system that included a hand broadcast seed spreader and the use of a 2-ft wide walk-behind BCS with roller-crimper for planting and termination of cover crop, respectively, and transplanting tomato plants by hand. This was compared to high-input technology that included a no-till grain drill, a 10 ft wide roller-crimper and no-till transplanter. In comparison to no-till high-technology or bareground systems, preliminary results showed that the residue mulch suppressed weed growth compared to bareground, which required three cultivations during the season. Tomato yield was almost similar to the high input system. Thus, in this trial low-input no-till technology can be considered a potentially affordable management system to support small-scale and biointensive vegetable farmers.
Effectiveness of using no-till with low-input technology has not been tested on growers’ farms and compared to growers’ management practices. John and Aimee Good, successful small-scale CSA farmers in Pennsylvania, are interested in reducing their dependence on seasonal cultivations and conserve soil health. It is essential to partner with farmers such as the Goods to evaluate whether the adoption of no-till practices using low input technology will be profitable for them as an alternative system to conserve soil health and sustain crop production for their CSA members.
The overarching goal of this project is to demonstrate low-input approaches that are affordable to small-scale and low-capital beginner organic vegetable farmers to improve crop productivity and quality and conserve soil from degradation. We propose a one-year project to address the following questions:
1) How effective is a low-input no-till technology system on conserving soil in comparison to standard farmers’practices (bare ground with multiple seasonal cultivations and black plastic) and high-input no-till technology? 2) Will the low-input no-till technology system improve crop productivity relative to standard farmer’s practice? 3) How effective are the proposed managment practices in managing weed pressure measured as weed density, weed biomass, and their relationship to yield? The specific objectives of this project are to: 1) Demonstrate that low-input no-till technology can be used effectively as a soil and weed management system by reducing cultivation and conserving soil; 2) Compare costs and benefits of using low-input and high-input no-till technologies on crop yield and nutrient content; and 3) Transfer this knowledge to small-scale, beginner vegetable farmers.
Field plots will be established at our collaborator’s farm in spring of 2016. In a randomized complete block design with four replications, winter squash will be grown on beds 4 ft x 30 ft (1.2 m x 9 m) per treatment per replicate. Dr. Zinati will coordinate with the collaborating farmers on field activities to ensure timely execution of treatments and collection of data.
The treatments at the partnering Quiet Creek farm:
- Grower’s standard method – Bareground Treatment: includes tilled in cover crop, transplanting with water wheel transplanter, and seasonal mechanical cultivation;
- No- till, low-input technology: includes rolling cover crops into mulch using a 2-ft wide walk-behind BCS roller-crimper and transplanting by hand. The BCS is a two-wheel small farm equipment with take off shaft to which any number of tools can be attached such as 2-ft roller-crimper, mower or tiller; and
- No- till, high-input technology: includes rolling cover crops into mulch using a 10 ft wide roller-crimper driven by tractor and transplanting with no-till transplanter.
At the Rodale Institute Research Farm, in a randomized complete block design with four replications, treatments 2 and 3 metioned above will be compared to black plastic treatment (includes tilled in cover crop, black plastic, transplanting with water wheel transplanter and seasonal mechanical cultivation). Winter squash will be grown in 10ft x 50 ft beds.
At the Good Farm a cover crop mixture of wheat, hairy vetch and crimson clover were established in September 2016 while at Rodale Institute Research Farm a cover crop mixture of cereal rye and Austrian winter pea were established in mid-September 2016.
Seedling beds will be prepared by tilling in cover crop mixture, disking, and shaping the beds for either bareground or laying down black plastic. No spring tillage is required for the low- and high-input technologies. Cover crop mixtures will be rolled-crimped with a 2-ft wide BCS crimper or a 10-ft wide roller-crimper, respectively.
Winter squash seedlings ‘Waltham’ (butternut) will be established in the greenhouse in mid-April- early May 2017. Seedlings will be transplanted into one row beds, with 24 inches spacing within rows, two weeks after bed preparation in late May-early June 2017.
Weed species such as ragweed, foxtail, galinsoga,and pigweed compete with the young winter squash seedlings during the growing season. The standard practice of weeding for bareground production is two to three mechanical cultivations before winter squash plant branching exceeds bed width. Additionally, in black plastic treatment 1-2 seasonal cultivations between rows is typical. Treatments with cover crop mulches require no cultivation. Winter squash will be harvested in late August or early September 2017 and cured in the greenhouse before distributing to CSA shared members in October-November 2017.
Soil health assessment:
Soil health measurements will be for physical, chemical and biological properties:
- At the partnering farmers’ site: composite soil samples (eight cores) from 0-20 cm deep will be collected three times during the growing season from each treatment from 3 replications (total of 27 samples), air-dried, sieved through 2-mm sieve and sent for chemical analysis (pH, macro and micro nutrients, organic matter, carbon and nitrogen) to the AASL at Penn State University. For biological analysis, 27 moist soil cores collected from top 0-8 cm deep will be put on ice in an ice chest and shipped overnight to Ward Laboratory for biological assessment. Soil samples will be collected at beginning of the season, mid-season (first signs of fruit formation) and before harvest. At the same time, physical properties such as bulk density and compaction will be determined in-house. A penetrometer will be used to measure sub-surface compaction by recording the soil depth at which root penetration is hindered (300 psi).
- At Rodale Institute Research Farm: A total of 27 soil samples will be assessed for chemical properties and another 27 soil samples for biological properites and sent to above-mentioned laboratories. Funding will be required for only 15 samples per each of chemical and biological analyses. For physical properties, soil samples will be determined in-house.Weed density and biomass:
- Assessment of weed density (number per area) and biomass (weight per area) will be conducted per each treatment, replicate and site before transplanting, mid season and before harvest. Weeds in 5.4 ft2 (0.5 m2) quadrants will be counted and cut, dried at 65 oC and weighed.
At harvest, Dr. Zinati will harvest and record number and weight of marketable and unmarketable fruits per treatment per replication and give the harvest to the Goods for their CSA shares. At Rodale Institue, Dr. Zinati and Dr. Smith will harvest and record number and yield per treatment per replication. Yield data will be included in a model with weed density and biomass to determine the yield-weed relationship in each system.
Statistics and data presentation:
Dr. Zinati and Dr. Smith will assess weed biomass and density, crop yield and quality, and soil health per site. Collected data on weed, yield, crop nutrient content, soil quality indicators, and profitability will be compiled, and analyzed by standard ANOVA using the generalized linear model (GLM) of SAS® 9.3. An enterprise budget of revenues and expenses will be prepared for each system based on inputs such as hours and cost of weeding, cultivation, farmer return, profit and benefits gained for soil health. Analyzed data will be presented in tables and graphs and written in technical and scientific formats.
Expectation of proposed method:
In this project, we will demonstrate the effectiveness of using low-input no-till technology as a viable option to small-scale and beginner farmers with limited resources as an alternative management system to cultivation, use of black plastic, and high-input no-till to improve soil conservation and enhance crop productivity.
At the grower’s site:
Samples of cover crop biomass were collected from 0.5 m2 quadrats on May 16, 2017, and dried in the oven for dry weight and nutrient analyses. Similarly, soil samples were collected at 0-20cm deep, dried and sieved for chemical analysis, however, for biological analysis samples were taken from 3 inch deep, packed in ice chest filled with ice and transported to Rodale Institute’s Laboratory and stored frozen until analysis. Similarly soil samples for physical, chemical and biological properties were taken at the end of the season before harvest. Soil bulk density and soil compaction were assessed at the beginning and the end of the season. The depths at which soil penetrometer readings were 300 psi were recorded and the averages of three readings per each treatment were used to determine the depths where root growth would be restricted.
The experimental field was flagged for three treatments: a) bare-ground treatment (referred to as grower’s standard), b) no-till low input treatment (referred to as BCS), and c) no-till high input treatment (referred to as RC). Only in plots that were flagged for the standard treatment, the cover crop was first flail mowed and then the soil was spaded twice with the Celli spader forming two rows per plot on May 19, 2017 (Photo 1).
The cover crop biomass in plots that were flagged for low- and high-input technologies was rolled and crimped twice, on May 24 and June 1st 2017 (Photos 2 and 3).
Seedlings of butternut squash ‘Waltham’ were transplanted into two rows per plot with 24 inch spacing between plants using the water wheeler trans-planter for the standard treatment (Photo 4) and no-till planter for the rolled-crimped plots (Photo 5). All seedlings received fish emulsion solution at planting. The Goods did not add any irrigation system to this study because they usually produce rain-fed winter squash.
Hand-hoeing and in-season cultivation were accomplished in the standard treatment on June 22 and July 10, 2017, respectively. In the rolled-crimped treatments weeds were only hand weeded once. Time spent on hand hoeing and weeding was recorded to compare cost and benefit of using the various management systems.
Leaf tissue samples (17 per treatment) were collected and placed in paper bags, oven-dried for four days at 55 C before they were ground and analyzed for nutrients at the PSU AASL. Winter squash fruits were sampled from 10 plants per treatment on August 29, 2017 and cured in a greenhouse for two weeks. Fresh post-cured weight of butternut winter squash fruits were recorded (0-day storage). Whole fruit subsamples were taken and stored for 0, 30, and 60 days in a cool and dark room to assess for sugars, nutrients and carotenoids concentrations. At the end of each storage period the fruits were weighed, cut open, subsampled the edible portion, and kept in a freezer at -20 C before they were further freeze dried for sugar, nutrient and carotenoid analyses. Although this last step was not listed in the submitted proposal it is important to note that in discussions with Dr. Zinati, the partnering growers (the Goods) became interested in learning whether the post-harvest fruit quality (weight, nutrition, and disease free) of winter squash will be similar or greater than those produced under their standard treatment. The Goods were looking into expanding their CSA shares to include winter squash fruits among potato and sweet potato in their winter shares (November- January) as an added income, it was important to take into consideration sampling of fruits per storage period during the current study and processing the samples for quality analyses.
Rodale Institute’s site:
Measurements on soil compaction were taken on April 11, 2017, followed by weed measurements, cover crop (rye and Austrian pea mix) biomass sample collection, soil sampling for physical and chemical analyses on May 11, 2017, following same methods listed under the grower’s section. The cover crop in plasticulture treatment was mowed using a flail mower and the soil was moldboard-plowed on May 11, 2017, then disked twice on May 11 and 16, 2017. The plastic mulch was laid on May 24, 2017 (representing the standard treatment) with drip irrigation. Cover crop biomass was rolled-crimped using a walk-behind BCS (representing the low-input technology treatment) and a 10-ft roller crimper front-driven by a tractor (representing the high-input technology treatment) on May 24 and June 1st, 2017 (Photo 6). Seedlings of butternut squash ‘Waltham’ were transplanted into two rows per plot with 24 inch spacing between plants using the water wheeler trans-planter for the standard treatment (plastic mulch, Photo 7) on June 1st, 2017 and no-till planter for the rolled-crimped plots (Photo 8) with drip irrigation on June 7th, 2017. All seedlings received fish emulsion solution at planting.
Weed free areas were established on July 11, 2017 and weed counts were recorded in 0.5 m2 quadrats. Compaction measurements using a penetrometer were taken on August 15, 2017. Leaf tissue samples were taken on July 6th, 2017. Winter squash fruits were harvested from weed-free areas on August 30th, 2017. Fruits were cured in the greenhouse for two weeks and subsamples of marketable fruits per treatment were weighed and stored at 0, 30, and 60 days in a dark cool room. At the end of each storage period, fruits were cut open and sections from the edible portion were stored at -20 °C. Frozen samples were freeze dried and will be sent, to Dr. Casey Barickman’s Laboratory at the Mississippi State University, for sugar and carotenoid analyses and to PSU AASL for nutrient analysis.
Cover crop biomass and plant height: The average height for the cover crop mix hairy vetch, crimson clover and wheat was 92.08 cm (36.25 in), 32.67 cm (12.86 in), and 57.10 cm (22.48 in), respectively. The mean cover crop mix biomass was 4,111 kg/ha (3,670 lb/acre). While this value may be satisfactory for standard grower’s treatment (cultivation), however, it was well below the threshold value (greater than 8,000 kg/ha) identified for consistent suppression for annual weeds under rolled-crimped management systems.
Weed species and biomass: Weed species were identified and were dominated by chickweed, henbit, aster, pennycress, and wild mustard. The mean weed biomass at the beginning of the season was 479 kg/ha (427 lb/acre). However, weeding was necessary in all treatments during the growing season. The low biomass of rolled-crimped cover crop did not provide a season-long weed control as it was expected.
Soil physical properties: Bulk density at the beginning of the season was 0.68 g/cm3 in standard treatment and 0.88 g/cm3 in rolled-crimped treatments. However, at the end of the season soil bulk density values increased to 1.00 g/cm3 in all treatments. Soil compaction values read by a penetrometer were not significantly different between treatments at the beginning 27.5, 23.63, and 20.40 cm (Standard, BCS, and RC, respectively) and at the end of the season 37.50, 35.00, and 35.00 (Standard, BCS, and RC, respectively). However, results showed that the soil was less compacted (greater readings) at the end of the season under any management system.
Rodale Institute’s site
Cover crop biomass: The rye/Austrian pea biomass was low, ranging from 2,987 kg/ha to 4,440 kg/ha total dry weight, which is below the minimum target of 8,000 kg/ha for good weed control in rolled-down cover crop systems. The low biomass of cover crop is attributed to the cool and wet spring season of 2017.
Weeds species and biomass: The field site was heavily infested with weeds. Chickweed, dandelion, and mustard were the dominant weed species in all treatments. The high weed biomass in the BCS and RC treatments (2,662 kg/ha) resulted in significantly lower crop yields than in plasticulture treatment (305 kg/ha).
Crop yield: The plasticulture treatment yielded 12,347 kg/ha (11,016 lb/acre) whereas the BCS and the RC treatments yielded 3,658 kg/ha (3,264 lb/acre). The plasticulture treatment out yielded the BCS and RC which may have been attributed to lower weed pressures, warmer conditions under plastic compared to rolled-crimped mulch, and more nitrogen availability to plants.
Soil physical properties: Average soil bulk density was similar between treatments ranging from 1.00 to 1.14 g/cm3. Soil compaction measurements at the beginning and end of the season in BCS and RC were 33.83 cm and 32.50 cm, respectively and they were not significantly different from those in plasticulture treatment (33.78 cm and 30.65 cm, respectively).
Preliminary results showed that the biomass of the cover crop mix was below the threshold level needed for consistent suppression of spring and summer annual weeds in rolled-crimped treatments. The partnering growers realized the importance of choosing the cover crop mix and its role in providing a high biomass of rolled-crimped mulch to suppress weeds and reduce weeding activities once they transition to using the proposed technologies. To start with, we recommend that for a successful production of winter squash in no-till low- or high-input technology management systems the growers have to select a field site that is not heavily infested by weeds. Soil compaction in proposed technologies (low-input and high-input) was similar and not different from that in standard treatment (cultivation).
After one growing season the soil compaction was reduced in all treatments. However, soil bulk density slightly increased at the end of the season compared to the beginning of the season. Statistical analyses of crop yields, weed diversity, and soil chemical and biological properties are underway. Videos on rolling crimping with BCS and 10-ft roller crimper will be prepared. Results from this project will be shared with growers at the Mid-Atlantic Fruit and Vegetable Convention at Hershey, PA end of January 2018 and summaries in a web article which will be posted on Rodale Institute’s web site.
Education & Outreach Activities and Participation Summary
Outreach and Education:
- John Good, our partnering grower was trained, interviewed, and videoed on the use of the 10 ft roller-crimper on June 16, 2017 (Photo 9). Two other growers (one of whom is a new grower) were trained on using the BCS on June 1 and June 5th, 2017 (Photos 10 and 11).
- The site was visited by researchers from Iowa State University on May 24, 2017, and by 21 farmers from Norway on June 13, 2017 (Photo 12) and 13 Argentinian delegates on June 7th, 2017.
- Twenty six farmer apprentices of the northeast region registered under the CRAFT (Collaborative Regional Alliance for Farmer Training) program and 12 interns were engaged in and demonstration and hands-on experience on measurements of soil compaction (Photos 13-16) and soil sampling (Photo 17) on June 28, 2017.
- Dr. Zinati showcased the project to the over 200 attendees of the Rodale Institute’s Annual Field Day and discussed the objectives and the equipment being used for rolling and crimping of cover crop on July 21, 2017 (Photo 18).
- An article was published in NEW FARM, fall issue of 2017 and was emailed to 10,000 readers on September 9, 2017.
AREAS FOR FURTHER STUDY
In addition to analyses proposed in this project, we would like to also assess the impact of management systems and storage periods on fruit quality; specifically minerals and carotenoids in the winter squash at post-harvest and at various storage periods. These analyses will benefit the project by providing additional data on nutrient density in winter squash fruits under different management systems. The data will address the grower’s interest in selecting management systems that improve soil and plant health and provide healthier, higher quality fruit for the consumer, while at the same time improving farm income.
In the future, we would like to test soil and foliar amendments such as compost and compost extracts for weed and nutrient impacts under these management systems.