Protecting Beneficial Arthropods in Ohio Orchards

PROJECT BACKGROUND
Our farm is a small family owned and operated fruit growing operation founded in the 1850’s. It is completely contained within our small village and has a number of residential neighbors. Nine distinct types of trees and small fruit are raised, although apples are our primary crop. We emphasize direct retail sales and U-pick methods of marketing our crops.

We have implemented several significant sustainable practices over the past 15 years. Tree row volume spraying was started about 15 years ago. We started avoiding harsh broad spectrum insecticides about 10 years back, and began to use pheromone traps scouting to time sprays five or six years ago.

PROJECT DESCRIPTIONAND RESULTS
Goal:
Numerous beneficial arthropods, including beneficial insects and predator mites, have been found in Ohio orchards. Could their populations be enhanced by using pest control strategies based on pest and predator populations, rather than on a calendar? Could spray applications be reduced and still achieve satisfactory fruit quality?

Process:
Two part-time scout/technicians were employed to monitor conditions in our orchards. Numerous other growers were enlisted as cooperators, both to broaden the experimental base and to increase awareness of the program. Approximately 330 acres of apple and peaches were enrolled for scouting. These blocks influenced pest control decisions on about 750 acres, all in North Central Ohio.

The scouts visited farms on a weekly basis to check traps and assess populations of both beneficial and injurious arthropods. Scouting reports were discussed immediately with the grower. In addition, a weekly newsletter was mailed to all cooperators with scouting results. Economic action thresholds were included, along with local degree day accumulations, thereby allowing individual growers to adjust their pest control strategies to pest pressures.

People:
Huron County Extension Agent Ted Gastier was primarily responsible for administering this project. The scout technicians were Eugene Horner and James Mutchler. Kathy Phillips, Mary Ellen Hamernik, and Cathy Weilnau, office secretaries, assisted with budgeting and preparation of the newsletter. Dr. Celeste Welty, Entomologist, and Dr. Michael Ellis, Plant Pathologist, provided assistance with the field day.

Cooperating growers included the following: The Joe Burnham family, Lloyd Dayton, William Dodd, Rich and Betty Eshleman, The William Gammie Family, Dean Hasen, The Haslinger family, The Kuns family, The William Lees family, The Malone family, The Dwight Miller family, the Moore family, Carl Poorman, Rolland Schumaker, Ron Novak, The Soviak family, The Steinbauer family, Ralph Walcher, and Larry and Dona Mae Welch.
Results:
Beneficial arthropods were observed at sometime in all participating orchards. Stethorus punctum and predator mites provided significant control of European red mite. There remain questions on the tolerance of these predators to several new miticides just introduced this year.

The number of sprays required for the season was reduced as compared to a calendar-based system. Additionally San Jose scale control was enhanced by scouting for the emergence of the vulnerable “crawler” stage for spray timing. Spray material was economized by spraying only those trees found to be infested.

Discussion:
There are numerous advantages to this program, as well as some disadvantages. We were able to save sprays, which reduced the toxicity pressure on the beneficials. We did have red mite, but Stethorus punctum kept them in check, thus saving another spray. There is also a public relations benefit. It is good to be able to say to my customers that we have a program in place to effectively target our fruit pests.

A disadvantage of a scouting based spray plan is that it is more complicated to plan and implement. Care must be taken not to endanger the scout with too recent sprays. Coordinating insect sprays with disease sprays is more complicated.

Plans to study the effect of ground covers on beneficials were dropped when it was learned that earlier OSU research showed no clear correlation. Budgeted funds were directed toward monitoring leaf damage from Spotted tentiform Leafminer, a perennial problem.

OUTREACH
Outreach consisted of several distinct parts. The weekly newsletter reached all cooperating growers, as well as Ag agents in our North-east District and other extension personnel. A survey of growers at season’s end indicated they found the newsletter to be useful in the management of their orchards.

Our farm hosted a “Twilight” meeting in mid-July and invited fruit growers to visit with both the scouts and Extension specialists. Thirty-five growers participated. The meeting included presentations by Dr. Celest Welty and Dr. Michael Ellis of OSU Extension. An orchard walk with scouting demonstrations was also conducted.

Our growers will be meeting December 4th for a “Fruit Breakfast” to share the results of this project.

In cooperation with OSU Extension we will be continuing our outreach at the Ohio Fruit Grower’s Congress (our state organization’s annual meeting) in February 1997. there will be two sessions on trapping and scouting, one basic and one advanced.

The results of this project will also be carried forward to a follow up project in 1997, funded in part by NCRSARE and hosted by Richard and Betty Eshleman of Clyde, Ohio. Growers have expressed interest in continuing some type of summer training session.