Determining the commercial viability of an exclusionary production system using disease-resistant columnar apple and sweet cherry cultivars

2005 Annual Report for LNE03-182

Project Type: Research and Education
Funds awarded in 2003: $137,169.00
Projected End Date: 12/31/2007
Region: Northeast
State: New York
Project Leader:
Peter Jentsch
Poma Tech Inc.

Determining the commercial viability of an exclusionary production system using disease-resistant columnar apple and sweet cherry cultivars

Summary

The project manager continued to develop the 5 ‘exclusion’ sites (including 1 CSA farm (Community sponsored agriculture), 2 commercial farms, 1 historic farm, and one research site at Cornell's Hudson Valley Lab.). The disease-resistant columnar apple and dwarfing sweet cherry trees planted in a v-trellis high-density system was maintained for optimum growth in preparation for 2005 fruit production. The addition of wood chip mulches, weed removal, use of the drip irrigation, and development of the fixed-canopy spray system (HVL site only) are being used to familiarize fruit growers with an integrated pest management system to protect against insect and vertebrate pests, hail and in the case of cherry, rainfall, without the use of synthetic and in some cases, organic pesticides.

The winter of 2004-05 was moderate compared to the previous year, causing slight fruit tree injury and minimum reduction of fruiting buds on apple and cherry throughout the Hudson Valley. Yet the project trees being in their 3rd leaf did not produce significant fruit quantity in 2004, as most commercial varieties typically come into production in their 4th and 5th leaf. Plans to conduct pollination and fruit related evaluations were postponed again until 2006. Given the lack of fruiting potential and cost of exclusion netting, the placement of netting to reduce insect and vertebrate damage to the fruit was added in spring 2005 and data to determine the efficacy of netting relative to non-netted plots were evaluated. The entomology department evaluated the degree of insect pressure and efficacy of netting versus the non-netted plots. They also collected weather data to determine the environmental factors related to the netting versus the non-netted plots plots, which is included in this report. The plant pathology department collected and analyzed incidence of apple diseases to determine the degree of fungicide resistance for each variety and to determine the major differences in diseases between plots.

In September of 2003 the pomologist at Cornell’s Hudson Valley Lab resigned to take a position at Penn. State and his replacement is only not been advertised with candidates being considered beginning thie winter 2006. This has indeed left a large void in the project, as much of the data collection required will now require fulfillment by other departments.

Objectives/Performance Targets

Spring 2005

The exclusion production system is to be developed on each of the 5 farms and research sites. Evaluation of insect and disease will be made. Weather stations will be established and maintained to record environmental data throughout the growing season.

1. PAK Unlimited provided the netted panels that were affixed to the production system used for exclusion.

2. Overhead spray system continued to be developed for canopy applications at the HVL site.

3. Continuation of weed management through the application of weed barrier of composted chipped hardwood for optimum tree growth.

4. Maintenance of plots including pruning for optimum tree growth was continued.

5. Weather stations were established to monitor two collection sites to determine environmental conditions within exclusion plots compared to that in an un-netted plot.

6. Incidence of insect fruit damage and foliar presence was determined through pre-June drop data collection. Data was analyzed and presented in this report.

7. Incidence of disease to fruit and foliage was determined through early-mid season data collection. Data was analyzed and presented in this report.

Summer 2005
Growers and researchers will begin management protocols while making evaluations throughout the growing season.
1. Researchers to maintain detailed records and costs of inputs to conventional, IPM, and organic blocks while following exclusion management protocols.

2. Pomology team was to conduct fruit tree trunk and canopy volume measurements for growth baseline initiated (Pomologist no longer resides at the HVL and a substitute department will conduct horticultural data in 2006).

3. Entomology team to continue ground cover management.

Fall 2005
Year-end report to be sent to researchers, growers and NESARE.

1. Write–up and analysis of data in each area of applicable study for year two.

2. Expenditures for establishment and management of each system compiled.

3. Foliar analysis for nutritional analysis.

Accomplishments/Milestones

Spring:
A total of 94 cubic yards of composted wood chip was added to the 5 sites to maintain weed control.
No additional nitrogen was required in 2005 as manure at planting provided adequate supplies for the third growing season.

Summer:
Technical time spent on weed removal was reduced by 75% from the previous year as reduction in weed composition was accomplished through the use of the second year mulch applications.

Insect, disease and weather data was collected and analyzed to evaluate the efficacy of the exclusion production system. Efficacy of the exclusion system for disease and insect management was significantly superior, producing than the untreated plots with no pesticide inputs.

Fall:
Soil and foliar analysis was taken and evaluation confirmed adequate nutritional status in production plots with higher levels of both available nitrogen and organic matter compared to the commercial plots as well as neutral pH levels.

The exclusion production system was well maintained on each of the 5 farms and research site. Growers and researchers began management protocols while making evaluations throughout the growing season.

Impacts and Contributions/Outcomes

The development of the exclusion system and education of growers to become involved with function of the exclusion system continued in 2005.

Elimination in the use of herbicides to manage weed competition through the use of wood chip mulch and elimination of fungicide applications for disease management through the use of disease resistant cultivars has dramatically reduced the number of chemical applications required for this system of fruit production. Elimination of chemical drift and worker exposure are apparent consequences using this method of pest management. Yet costs for labor in weed management continue to have offset any monetary savings that might have been realized in chemical and application reduction.

Poster kiosks describing the project are established on farm sites and in retail markets affiliated with individual project farms and will continue in the spring to broaden the community awareness of the project and its implication on fruit production, as well as benefits to apple and cherry consumers. Grower and community interest in non-spray apple production in commercial, historical / visitor based site, and pick you own sites where projects are visible, continue to develop.

Significant reductions in pest damage to foliage and fruit within the exclusion plots were realized this season. No significant differences between apple varieties for insect variables were observed with the exception of OBLR feeding. High pressure from tarnish plant bug, plum curculio and leafroller larva caused considerable damage to the un-netted fruit, which exhibited a 22% clean fruit rating mid-season. In contrast, the exclusion plots experienced nearly 75% clean fruit, most of the damage (17%), to our astonishment, being caused by wind abrasion of the netting that caused callusing to the fruit surface.

The entomological data seems to suggest that commercial releases of beneficial predatory and parasitic insects may have contributed to the control of pest insects within the exclusion plots. Trichogramma minutum releases to the exclusion plots only, for egg parasitism of summer obliquebanded leafroller (OBLR) generation, was initiated 5 days after the first OBLR adult emergence. Releases were made to optimize on early parasitism of eggs. Since the plots were infested during the previous year with overwintering OBLR larva, and the similar quantity of foliar damage occurring in both exclusion and un-netted plots, it seems likely that T. minutum impacted the second generation to reduce fruit damage to less than 10% in the exclusion plot versus 32% fruit damage in the un-netted plots. Applications of Hippodamina convergens were also made for aphid control, yet environmental conditions and natural predation eliminated aphid populations in the un-netted plots prior to data evaluations.

Treatment effects on disease pressure were observed this year with lower overall disease pressure recorded within exclusion plots. This is believed to at least partially be the result of higher temperatures within the exclusion plots reducing the initiation of apple scab development early in the season. Recorded weather perimeters reveal approximately a four to five degree oF difference between exclusion and un-netted plots. This slight rise in temperatures may be responsible for reduced disease incidence. Wind reductions of > 75%, the possibility of reduced inoculum exposure due to the filtering aspect of the netting, and lower relatively humidity within exclusion plots may have been partially responsible for reduced disease incidence.