In This Issue:
Calendar
American Fruit Grower - Highlights Rich Eshlemen
Analysis of Pesticide Use in North Central Ohio Orchards, 1999
Apple Storage Concerns
January 13-14: Greenhouse Food Production Workshop, OARDC Fisher Auditorium, Wooster. Contact Mary Donnell, (419) 354-6916,
January 24-26: Indiana Horticultural Congress, Adam's Mark Hotel, Indianapolis, IN. Contact Jim Simon at (716) 494-1328 for more information.
January 28-30, Power Show Ohio, Ohio State Fairgrounds, Columbus, Ohio.
February 7-9: Pre-Conference Tours for the Ohio Fruit & Vegetable Growers Congress in conjunction with the North American Farmer's Direct Marketing Conference and Ohio Roadside Marketing Conference, Cincinnati, OH. For information contact Mike Pullins at (614) 249-2424.
February 10-12: Ohio Fruit & Vegetable Growers Congress, Cincinnati, OH. More details later.
Background
Producers enrolled in the North Central Tree Fruit Integrated Pest Management (IPM) Program post spray records at a location accessible to the scout/technicians. This allows for the protection of those people, as well as providing a source of information for analysis of orchard pesticide use. This report will look at pesticide use on the basis of "dosage equivalents," "environmental impact quotients," and cost of materials.
Dosage equivalents are based on the application of labeled rates; one dosage equivalent is defined as one application of a pesticide at the recommended rate that is needed for control of a given pest. When the recommendation is a range, the midpoint is considered the dosage equivalent, or DE. Sixty-nine pesticides and formulations labeled for apples and peaches were included.
Environmental Impact Quotients (EIQ) are useful as a method to measure the environmental impact of pesticides. In most IPM programs, pesticides are chosen on the basis of their efficacy or cost rather than on their potential environmental impact. Cornell researchers have ranked pesticides by environmental impact, which was included as a chapter in the Encyclopedia of Environmental Analysis and Remediation, available from John Wiley & Sons, Inc. A condensed version, with a table including in alphabetical order over 200 pesticides, is available from this web site: http://aruba.nysaes.cornell.edu/ipmnet/ny/program_news/EIQ.html.
The values of individual effects of each pesticide (applicator, picker, consumer, groundwater, aquatic, bird, bee, beneficials), the major components of the calculations (farm worker, consumer, and ecological), and the average EIQ values are presented in the table.
The costs per dosage equivalent were calculated from the price list of a major orchard supplier in Ohio. A mid-season (July) payment date was selected.
Results and Comments
The pesticides were divided between fungicides (including bactericides), insecticides, and miticides with values for individual blocks of DE and season costs for 18 apple and 6 peach blocks. In apples, the dosage equivalents applied ranged between 7.56 to 20.72 and costs per acre between $118.91 and $365.02. The average DE was 16.26, which compares favorably with 17.06 in a New York study. The greatest variation between blocks was in the use of fungicides. A more normal expectation would be that fungicide DEs would match the sum of insecticide plus miticide DEs, rather than the roughly 2 to 1 ratio experienced in 1999. Growers had experienced heavy disease pressures (particularly apple scab) in the 1998 season, and some were reluctant to reduce protective sprays.
The dosage equivalents applied in the peach blocks ranged from 7.65 to 12.70 and costs per acre between $124.14 and $254.32.
An examination of EIQs per dosage equivalents: the average was 1600 in the apple blocks and 1566 in the peach blocks. These are particularly high, as we would expect EIQs to be about 1000, according to the Cornell work. An explanation lies in the use of Ziram and Polyram for apples, and Ziram and sulfur for peaches. These are the EIQs per dosage equivalents for these and other fungicides:
Sulfur = 778
Ziram = 467
Polyram = 134
Captan = 86
Syllit = 68
Topsin M = 54
Nova = 4
Rubigan = 2
A better EIQ model was created for apples excluding Ziram and Polyram, resulting in an EIQ rating of 586, and actually reducing season cost by $10.50 per acre. For peaches, a better EIQ model without Ziram and sulfur yielded an EIQ rating of 595 at an additional cost of $5.20 per acre.
By using EIQ, IPM practitioners and growers can incorporate environmental effects, along with the efficacy and cost, into the pesticide decision-making process.
Ted W. Gastier
Extension Agent, Agriculture
Tree Fruit Team Coordinator
Ohio State University Extension Huron County
180 Milan Avenue
Norwalk, OH 44857
Phone: (419)668-8210
FAX: (419)663-4233
E-mail: gastier.1@osu.edu
Information presented above and where trade names are used, they are supplied with the understanding that no discrimination is intended and no endorsement by Ohio State University Extension is implied. Although every attempt is made to produce information that is complete, timely, and accurate, the pesticide user bears responsibility of consulting the pesticide label and adhering to those directions.
All educational programs conducted by Ohio State University Extension are available to clientele on a nondiscriminatory basis without regard to race, color, creed, religion, sexual orientation, national origin, gender, age, disability or Vietnam-era veteran status.
Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, Keith L. Smith, Director, Ohio State University Extension.
TDD # 1 (800) 589-8292 (Ohio only) or (614) 292-1868