Developing Integrated Pest Management Protocols for Northeast Organic Apple Production

Developing Integrated Pest Management Protocols for Northeast Organic Apple Production

Summary

During the 2010 fruit growing season, in collaboration with USDA-ARS Appalachian Fruit Research Station (Tracy Leskey / Starker Wright) and Geneva Experiment Station (Harvey Reissig) we evaluated similar pest management programs on two uniquely different organic apple orchard systems owned by Steve Clarke of Clarks Farms in Modena, NY and Fabio Chizzola of Windward Orchard in Accord, NY. The insect pest management programs employed

Surround WP (50 lbs./A at TC, P, PF, 1C),
Isomate twin ties for mating disruption of Oriental fruit moth (OFM): Grapholitha molesta (Busck) and Codling moth (CM): Cydia pomonella (Linnaeus), (applied at 1st pheromone trap catch at 200 ties./A), Cyd-X (4 oz./A @ 4 applications 10d intervals for each of 2 codling moth generations beginning at 1st hatch or 250DD50),
the use of Entrust and GF-120 combinations for Obliquebanded leafroller (OBLR): Choristoneura rosaceana (Harris) and Apple Maggot (AM): Rhagoletis pomonella (Walsh)
in conjunction with baited red spheres (aptly named ‘Curve Balls’), a trap and kill alternative technology to control damage on apple, employed in pest control strategies.

Apple tree fruit phenology was two to three weeks ahead of insect development leading to significantly lower levels of European apple sawfly (EAS): Hoplocampa testudinea (Klug) and plum curculio (PC): Conotrachelus nenuphar (Herbst) injury in the mid-Hudson Valley.

In Milton, NY, significantly lower levels of insect damage was observed in season long management of disease resistant varieties on dwarfing M-9 rootstock using a high density slender spindle planting system. However, in Accord, NY, employing standard trees approximately 22-30’ high on a 25’ x 25’ spacing using similar rates and timings of the same pest management programs, demonstrated significantly higher levels of insect damage occurred from PC occurred.

Excellent control was achieved from fruit managed in the high-density block at Clarks Farms in Modena, with management providing over 89% clean fruit across the orchard. However, 98% fruit damage was observed in Accord. Differences in application coverage, spacing and insect density play important roles in observed differences between farms.

Objectives/Performance Targets

The objective of this study was to evaluate the efficacy of a diverse and comprehensive, OMRI approved pest management program and a experimental method likely to be approved for organic apple production, used to control late season apple maggot damage. Evaluations of two distinctly different organic orchards: one being a 5-acre high-density block of mixed varieties of disease resistant NOFA certified apple and the other, a newly renovated transition orchard of disease susceptible varieties on standard seedling stock using traditional spacings. These sites were chosen for their stark differences in design, historically high PC and AM population damage levels, and marketing dynamics.

Milton, NY: The mixed variety block containing scab resistant varieties included Honeycrisp, Liberty and Golden Supreme, Red Free varieties. Two rows of mixed Cortland and Red Delicious are also included in the organic block.

Tree phenology beginning with
green tip (GT) on 20 March,
1/2” Green on 2 April,
tight cluster (TC) on 6 April,
Pink (P) on 10 April,
King Bloom on 20 April,
petal fall (PF) on 28 May @ 80% PF of ‘McIntosh.

Actual PF applications on 30 May, 1C on 11 May, 2C on 2 June, 3C on 11 June, 4C on 24 June, 5C on 16 July, 6C on 31 July.

1st generation of CM using 250DD50 for larval emergence on 2 June; 2nd application for 1st Gen. CM using 360DD50 on 11 June; a single 2nd Gen. CM application on 16 July after 250DD50 from 1st adult pheromone trap capture.
The 1st AM adult fly caught on 21 June with threshold occurring on 15 July.

Trees on the M.9 rootstock were approximately 12 ft high, 12’ wide, and planted to a commercial spacing of 7’ x 20’ to 520 trees/A. The treatment applications were made using a tractor mounted conventional airblast sprayer made at 100 GPA, 160 psi at 3.2 mph,

using Surround WP at 50 lbs./A applied at TC, P, PF, 1C;
Isomate twin ties for mating disruption of Oriental fruit moth (OFM): Grapholitha molesta (Busck) and Codling moth (CM): Cydia pomonella (Linnaeus), were applied at 1st pheromone trap catch using 200 ties./A,
Cyd-X applied at 2C-5C using 4 oz./A @ 3 applications and a single application at 5C for the 2nd generation of codling moth beginning at 1st hatch or 250DD50,
the use of Entrust and GF-120 combinations for Obliquebanded leafroller (OBLR): Choristoneura rosaceana (Harris) and Apple Maggot (AM): Rhagoletis pomonella (Walsh)
in conjunction with baited red spheres (aptly named ‘Curve Balls’), a trap and kill alternative technology to control damage on apple, employed in pest control strategies at threshold of AM at 5-6C.

The latter part of the season we used a split block design employing Curve Balls at 1 sphere per tree in the eastern ½ of the block while Entrust and GF-120 combinations were employed in the alternate western portion of the block. The Curve Ball are baited red spheres in which the insecticide Entrust (spinosad) is impregnated into a wire mesh paraffin wax and sugar base cap, hung to densities of 1 per 100 fruit. Spheres were applied to 7 rows within the block along with volatile attractant to increase attractiveness. Each split block was separated by a boarder row of untreated apple.

Accord: This mixed variety block of three acres containing seedling scab susceptible varieties included McIntosh, Cortland and Red Delicious, approximately 30’ high and planted to a traditional spacing of 25’ x 25’ with approximately 50 trees/A given the missing trees in the block. The treatment applications were made using a tractor mounted conventional airblast sprayer made at 150 GPA, 180 psi at 2 mph. The timing for the Accord farm was slightly different from Milton as higher levels of PC damage were observed.

The interval from PF to 2C was tightened to 10 day intervals to attempt to reduce damage from EAS and PC.
Surround WP at 25 lbs./A was applied in 2 applications at TC, P, and at to 50 lbs./A at PF, 1-2C. However, poor agitation and inadequate coverage from a low output fan and pump did not provide the developing fruit with a sufficient dilution of kaolin clay to cover fruit and keep PC from damaging nearly 100% of the developing fruitlets. In part this was due to the height of the tree, relative to the dispersal of kaolin droplets, and relative low levels of fruit per tree relative to very high levels of PC adults.

Mating disruption was initiated however, given the significant fruit loss shortly after fruit set, Cyd-X was not applied. Curve Ball control strategies were initiated at the first AM fly capture at 3-6C. Entrust alone was applied at 3 oz./A at 340DD43 for Obliquebanded leafroller control.

The 2010 petal fall date was the earliest on record at the Hudson Valley Laboratory occurring on the 28th of April, 15 days earlier than the mean. The degree day accumulations for that date were also lower than previously recorded for petal fall with 305 degree days base 43; 177 days earlier than the mean and 92 DD earlier than the previous low accumulation which occurred in 2007.

Pre-bloom insect populations were delayed in their occurrence with low population pressure from rosy apple aphid (RAA): Dysaphis plantaginea (Passerini), tarnished plant bug (TPB): Lygus lineolaris (P. de B.), and OBLR. Post bloom insect occurrence was dominated by TPB. EAS, which oviposit on flower clusters, occurred primarily in late blooming varieties with very low levels of damage this season. Very low levels of plum curculio were observed in late migration predominately on mid and late flowering varieties. The low incidence of EAS and PC, coupled with the low levels of apple scab, allowed for high numbers of abandoned fruit to remain on the trees this summer. This will provide high inoculum levels of internal lep and AM to over winter this season

Early season insect pressure being quite low led some growers to reduce 1st and 2nd cover applications of insecticides. This provided the internal lepidopteran complex (OFM and CM) opportunity to damage apple, observed primarily in the eastern Hudson Valley region. Frass appeared somewhat later than predicted during mid to late June given the early fruit maturation. Relatively high levels of the internal lepidopteran complex (15.3% for 1st generation; >28% for 1st and 2nd generation combined at harvest) were observed in untreated controls (Rogers McIntosh 1st gen. only; red delicious 2nd gen. at harvest) by the end of this season.

Growers monitored Obliquebanded leafroller closely this season in many Hudson Valley orchards. Applications were made using DD based insect phenology predictions for early emergence. In general, very low damage levels of OBLR observed this season.

Apple maggot density was relative depending on scattered rainfall patterns throughout the region. Very high populations were noted in the northern Hudson Valley where rainfall provided ideal emergence conditions, while few flies were observed in weekly counts to the south. In general, the insects observed slipping through the cracks this season were San Jose scale (SJS): Quadraspidiotus perniciosus (Comstock), the Stink bug complex (SB): Green stink bug, Acrosternum hilare (Say); brown stink bug, Euschistus servus (Say), CM, and AM (in northern Hudson Valley orchards). We noted that 50% SB damage observed in a block of golden delicious in a southern Hudson Valley orchard, leading to the abandonment of the block. Higher numbers of Brown Marmorated Stink Bug, Halyomorpha halys, (BMSB) have been observed throughout the southern Hudson Valley this fall. Fruit in research blocks are showing earlier SB feeding damage that may be caused by BMSB yet all three species including dusky brown and green SB have been noted on fruit throughout the very dry late season.

Accomplishments/Milestones

In this first year of evaluating a comprehensive organic program we were able to determine the efficacy of stratified OMRI certified insect pest management tools in two very different orchard environments. However, it must be said that one years data does not imply sustainable effectiveness of any given program and as such, multiple years of testing should be required with similar results prior to investing in a said program.

Milton: That being stated, the use of these products appeared to most effective in a high density planting system in high yielding systems where excellent coverage of fruit can be obtained and high volume of fruit ‘dilutes’ the levels of insect damage, thereby reducing the overall percent damage levels. Surround in pre-bloom applications was ‘stratified’ onto developing foliage and fruit prior to PC emergence. The material performed well in systems with high holding capacity of dense foliage for repellency and greater re-distribution during rain events. The combination of Isomate OFM/CM twin ties and Cyd-X significantly reduced the internal lepidopteran population from the previous seasons damage of 41% CM in the 1st generation to over 80% damage by the 2nd generation at harvest. Natural population levels of apple maggot were much lower than the previous year, most likely due to extended drought conditions in the lower Hudson Valley, thus reducing the overall AM population and damage levels to fruit at harvest. Curve ball trap density using 1 trap per tree gave acceptable organic control of apple maggot, slightly less control than did the Entrust / GF120 combination treated fruit applied during the peak AM emergence. At this stage of development it is difficult to say that the GF120 and Entrust would have provided economic savings above the cost of the Curve ball, yet if OBLR or other leafroller (LR) are present to cause significant damage to fruit, then there is added benefit for its use in LR management.

Impacts and Contributions/Outcomes

2010 was the most productive and profitable year the Clark organic orchard has had to date. Steve Clark had not only the highest yield per acre but the highest level of clean fruit and using the Union Square markets in New York City, was able to carry more volume this season while the market provided high pricing for premier varieties such as Honeycrisp and Golden Supreme. Steve Clark was pleasantly surprised at these results and will continue to use multiple pre-bloom applications to obtain the stratification of clay on his trees to keep PC from becoming established in the orchard. He plans on continuing to use mating disruption and codling moth virus to maintain low levels of internal lepidoptera and is uncertain about which direction to go regarding apple maggot. Although Surround WP works well against AM, the residue at harvest is a real disadvantage, requiring a considerable amount of work to remove.

WestWind orchard has already decided to transition his large trees to pick your own with minimal management while establishing a high density planting of newly developed high density disease resistant varieties on G11. His goal is to maintain the aesthetic charm of his old orchard, purchase a high volume handgun sprayer for high dilute and pressure applications to manage these beautiful trees while establishing and sell fruit from the newly developed tall spindle trees. He estimates that he will produce over 1000 bu./year by the 4th year, allowing him to pay off his investment.

Collaborators: