Sustainable pest management in high tunnel winter greens production

2013 Annual Report for LNE10-302

Project Type: Research and Education
Funds awarded in 2010: $79,668.00
Projected End Date: 12/31/2013
Region: Northeast
State: New York
Project Leader:
Judson Reid
Cornell Vegetable Program

Sustainable pest management in high tunnel winter greens production


Interest in growing winter greens continues to remain high in NY, as evidenced by high enrollment numbers (35 people) for our Dec. 4th Winter Greens Production School. Many of the attendees (57%) are considering greens production, and only 14% have grown greens for more than 2 seasons. Demonstrations at local farms, statewide meetings, and regional schools also conveyed key winter pest management information gathered during this project, reaching 217 people (10 events total) during this reporintg period. On-farm case study trials were conducted at 10 farms in 9 NY counties in the 2012-2013 growing season. Data was collected on efficacy of several management options for aphids, slugs, and caterpillars, preferences of pests for certain hosts, and the impact of cultural practices on pest populations. Cooperator surveys showed measurable gains in pest management knowledge and skills. All 4 2012-2013 cooperators receiving a verification visit (Fall 2013) have shown adoption of techniques taught through this project. 7 sites in 4 WNY counties were recruited for the 2013-2014 season to continue on-farm work. Regular scouting has led to early and successful pest intervention on several farms in the 2013-2014 growing season.  

Objectives/Performance Targets

The overall performance target for this project is that 20 high tunnel growers will adopt biological or biorational control methods to manage pests of cool season greens gaining $2000 of marketable product per season. Progress toward meeting that target is confirmed by the completion of the following milestones:

  • Statewide winter meeting reaches 40 growers – January 23 2013
  • Continue on-site grower trials – Sept. 2012-March 2013, Aug. 2013-Spring 2014
  • On-farm meeting demonstrates methods to 40 growers. – May-Dec. 2013


  • Statewide winter meeting reaches 40 growers
    • 55 people attended a presentation at the Empire State Producers’ Expo – Jan. 23, 2013.
  •  Continue on-site grower trials.
    The project team worked with 10 growers in the winter of 2012/2013 to conduct on-farm pest management case studies. The work is continuing in the winter of 2013/2014, with seven growers participating. Growers learned to recognize pest damage, identify the causal pest, select and use biological or biorational controls, and to account for the impact of cultural and general management practices in mitigating pest problems. The project team gained an increased understanding of the influence of cultural practices, crop type and canopy structure, and temperature on the severity of pests and the efficacy of various control measures. Greater details of each case-study site is available in the attached Case Studies document.
    • On-farm meeting demonstrates methods to 40 growers.
      • The following meetings contained on farm demonstrations, education on winter pest management techniques, or discussion of adopting farmers’ experiences:

March 8th, Busti Cider Mill and Farm Market, Busti, NY-8 growers
May 8, Canticle Farm, Allegany, NY – 5 growers
June 12, Quest Farm, Almond, NY – 8 growers July 12, Hector, NY – 5 growers
October 9, Native Offerings Farm, Little Valley, NY – 8 growers
October 15, Fisher Hill Farm, Canandaigua, NY – 13 growers

Additionally, 35 people attended the High Tunnel School – Winter Greens Production Day held in Batavia, NY on December 4. The intensive school had a heavy pest management focus: two presentations related to preventative and reactive pest management, grower experiences with pest management, an on farm tour at a 2012-2013 cooperating farm (Kent, NY), and an in-field scouting lesson. Participants included established greens farms, farms considering winter production, urban farming and school gardening program coordinators, and research and extension professionals.

Geographical Distribution of Winter Greens Production School Attendees (Batavia, NY)

Similar meetings were held on December 9th in Paul Smiths and on December 13th in Voorheesville, NY. These meetings reached an additional 80 growers in the northern and eastern regions of the state. Structural design and siting influences on diseases of winter grown greens were among the topics at these meetings.


  • Adoption surveys mailed to 200 growers contacted during the project

Grower contact information is being compiled and survey questions are being refined. Survey distribution is anticipated in early February of 2014, with analysis completed by June 2014.

  • Adoption verification via minimum of 20 farm visits.

Adoption is measured by observed changes in production techniques and changes in grower knowledge and attitude regarding winter pest management. To date, four grower cooperator farms have been visited, and all have demonstrated adoption. Farm visits are planned for the winter of 2014 to continue verification.


Impacts and Contributions/Outcomes

The ten farms participating in case studies in the 2012-2013 season were surveyed to measure their knowledge and skill gain through this project. The attached table shows their agreement with common winter pest management statements. Overall, grower cooperators showed a significant increase in their knowledge and skill set regarding common winter pests.

Grower comments related to the project include:

“I found this project to be very beneficial. Has taught me a lot and I am able to plan better for next season’s high tunnel production.” – Monroe County cooperator

 “It was nice to get an understanding of the issues (insect, disease) we face and how to combat them.” – Cattaraugus County cooperator

 “It was very helpful to have regular scouting in the tunnel and that enabled me to better understand the pest & disease issues.” – Ontario County cooperator

 “Thank you for the opportunity to participate in the project. The regular interaction with [the] project field representative…was a great learning experience for us. We will take the knowledge we gained working with her and improve our 2013/2014 winter greens crops.” – Allegany County cooperator

 Labor Impact
Of the 6 farms that had previously grown greens, 3 found that improved pest management led to less pest pressure and also an easier harvest when compared to the 2011-2012 season. 2 growers also reported spending less time sorting greens after harvest when compared to the previous year. Overall, 4 of the 6 farms found that an improvement in pest management led to decreased labor inputs.

Skills/knowledge impact for project team
A common theme of the 2013-2013 winter growing season was the influence of environmental conditions on the presence and severity of pest populations in winter greens. For example, at some farms it was observed that weedy sow thistles growing near tunnels often were infested with large black aphids. Farms that did not remove the weeds suffered an aphid migration into the tunnel following frost. The aphids found lettuce a suitable alternative and were difficult to control in the crop. It was also observed that slug pressure was more intense in wetter areas of tunnels, such as points where external water infiltrated. Additionally, slugs caused more damage when there was a dense canopy cover that created a dark, humid environment. Weed management and good crop spacing were demonstrated to be important factors and viable management options for pest control.  

Host preferences and the influence of canopy on success of aphid controls were also studied in 2013. Cabbage caterpillars are destructive to brassicas, while cutworms feed more indiscriminately. Woolybears prefer bok choi over chard. Aphids, with the exception of those moving in from weedy sowthistles, could be found first and in higher concentrations on leafy brassicas. They were often first observed on the lower leaves of kale. Once established, aphids prefer sheltered canopy areas, such as the whorl of pak-choi type vegetables, inside the curled margins on developing chard leaves, and deep within a lettuce head. This had a profound impact on the success of control tactics. Contact biofungicides are unable to reach aphids in many of those places. Ladybeetles or parasitoid wasps performed much better in dense canopies and areas where good spray coverage is difficult to obtain.

 We have also noticed an increase in disease incidence in 2013. On average, diseases accounted for 41% of lost marketability on cooperator farms in the 2012-2013 season. In all cases, excess relative humidity, or soil moisture, are causal factors. The system itself makes humidity management challenging. Growing winter greens in high tunnels is really about growing in low tunnels. Cornell Vegetable Program research has repeatedly shown that a high tunnel itself is not effective at protecting crops from low temperatures. The addition of low tunnels (hoops with row cover), traps enough heat in the soil and canopy to allow the production of greens in NE climates all year long.   However, the low tunnels also trap humidity which increases the opportunity for diseases, such as Gray Mold or Downy Mildew.

 Similarly, we are seeing increasing crop losses from less common winter pests: leaf miners (chard and spinach), spinach crown mites (spinach) and vertebrates such as voles (fleshy brassicas, head lettuces, leafy brassicas). Their damages during winter production can be significant, and lead to major losses. Spinach crown mite is particularly damaging – one farm lost 20-30lbs of spinach, another attributed 89% of lost spinach to crown mite.

Work in 2014 will continue to examine these on farm observations and to evaluate the impact of this project on the expanding winter greens production community in New York State.


Elizabeth Buck

Extension Aide
Cornell Vegetable Program
420 Main St
Batavia, NY 14020
Office Phone: 6074253494
Kathryn Klotzbach

[email protected]
12690 Route 31
Albion, NY 14411
Office Phone: 5857984265
Dr. Brian Nault

[email protected]
Associate Professor
Cornell U. Dept of Entomology
Baron Laboratory-NYSAES
610 W. North St
Geneva, NY 14456
Office Phone: 3157872354