William M. Coli

Effect of understory and border vegetation composition on phytophagous and predatory mites in Massachusetts commercial apple orchards

Abstract Ground cover and border composition were determined using ordination in 28 Massachusetts commercial apple orchard blocks. The presence or absence of phytophagous and predatory mites was recorded after 2 min timed scans of ten randomly selected apple leaves and of the five most commonly occurring plants at ten aisle, row, and border sampling sites. Orchard ground cover vegetation was very diverse. Grasses were the predominant ground-cover in aisles, with broadleaf plants predominant in the rows. Orchard borders were somewhat less diverse than the orchards themselves. Rubus spp. were the most frequently occurring border plants. All types of phytophagous and predatory mites examined were significantly more likely to be found on herbaceous forbs and woody plants (dicots) than on grasses (monocots).

An assessment of grower perceptions and factors influencing adoption of IPM in commercial cranberry production

A survey was developed and distributed to the Massachusetts cranberry grower community in 1999 to identify biological, educational, social and political barriers to the adoption of available integrated pest management (IPM) practices. The response rate for the 450 growers who received the survey was 54%. Approximately 80% of respondents claimed to practice IPM frequently and 16% identified themselves as occasional practitioners. Most growers practiced IPM because they agreed with IPM philosophy (80%) and believed it had environmental benefits (73%). Ninety-two percent agreed that more IPM-related research and education programs would encourage them to adopt practices they are not currently using. A significant percentage of respondents used multiple IPM component practices, with practices involving monitoring and detection of pests along with judicious use of pesticides being most common. Factor analysis was used to condense 104 potential responses to 22 factors, which were then used as predictors with six demographic variables (IPM adoption, education level, age, experience, farm size and work status). Demographic factors influenced a growers tendency to incorporate IPM into routine farm activities. Full-time, highly experienced growers in charge of large operations tended frequently to use more IPM practices than less experienced growers who worked part-time and managed smaller farms. A large proportion of respondents agreed that IPM can reduce pesticide residues in food (92%) and the environment (96%), and can help to preserve beneficial insects (96%). Although many growers held the perception that IPM can pose measurable economic risk (and subsequently act as a barrier to adoption), growers appeared to feel less strongly about the economic benefits than potential environmental ones.

Second-level integrated pest management in commercial apple orchards

As historical background helpful to understanding current concepts and practices of apple pest management, we review the origin and rise of key pests of apple in North America and the evolution of approaches to their management, culminating with the concept of integrated pest management (IPM). We propose four levels of integration of orchard pest management practices. First-level IPM integrates chemically based and biologically based management tactics for a single class of pests, such as arthropods, diseases, weeds or vertebrates. Second-level IPM, the focus of our effort here, integrates multiple management tactics across all classes of pests. We describe components of second-level IPM for Massachusetts apple orchards, which are threatened each year by an exceptionally broad range of injurious pests. We illustrate the tentative advantages and shortcomings of second-level IPM using 1993 data from six commercial orchard test blocks. Our predominant approach was to use chemically based tactics for controlling arthropods, diseases and weeds early in the growing season, and afterwards to rely exclusively (for insects) or largely (for other pests) on biologically based tactics, such as cultural, behavioral, and biological controls. Compared with nearby first-level IPM blocks, insecticide use in 1993 was reduced substantially (about 30%), with only slightly more insect injury to fruit and little difference in populations of foliar insect pests. The results for mite pests and diseases were less encouraging although summer pruning significantly reduced disease injury caused by flyspeck. We discuss how second-level IPM poses special biological or operational challenges to apple pest management practitioners. The concept has merit, but refinements are necessary before it can be recommended broadly to commercial apple growers in Massachusetts as an economical and reliable alternative to first-level IPM.

IPM adoption in northeastern U.S.: An examination of the IPM continuum

Survey data from sweet corn, strawberry, apple, and potato growers in nine northeastern U.S. states were used to assess relative levels of adoption of integrated pest management (IPM). Grower adoption of an IPM system was measured by assigning numerical values for completion of specific management practices, and summing the number of practice points. Practices included those for management of soil, nutrients, weeds, diseases and insects, and education. Numerical scores were used to describe IPM adoption as a continuum, with growers classified as low, moderate, or high adopters based on their completion of practices. The relative level of IPM adoption varied among crops and states. Forty-nine percent of sweet corn growers were found to be moderate-to high-level IPM adopters, while 76% of strawberry growers, 90% of potato growers, and 69% of apple growers were moderate- to high-level adopters, respectively. Variation among states with respect to adoption of IPM is described and discussed.

Use of visual traps for monitoring insect pests in the Massachusetts apple IPM program

Abstract Visual traps were evaluated for effectiveness as monitoring devices for the tarnished plant bug (Lygus lineolaris, TPB), European apple sawfly (Hoplocampa testudinea, EAS) and apple blotch leafminer (Phyllonorycter crataegella, ABLM). Results indicate: 1. A significant positive linear relationship between on-tree fruit injury surveys and cumulative captures on white, sticky-coated rectangles of TPB adults, for the tree development periods silver tip through tight cluster or silver tip through late pink, and for captures of EAS adults in blocks receiving no pre-bloom insecticide sprays. 2. A significant positive relationship with linear and quadratic components between on-tree fruit injury surveys and cumulative captures on white rectangles of EAS adults in blocks that did receive pre-bloom insecticide sprays. 3. A significant positive relationship with linear and quadratic components between peak mines per leaf and cumulative captures of ABLM adults on tent-shaped, red enamel (sticky side up) traps for silver tip through late pink or silver tip through two weeks past petal fall. Provisional economic injury levels are suggested as 2.0% and 0.7% fruit injury and 0.13% mines per leaf for TPB, EAS and first generation ABLM, respectively. Provisional action threshold levels based on these economic injury levels are presented for TPB (cumulative capture of 2.4 per trap for silver tip through tight cluster or 4.2 per trap for silver tip through late pink respectively), EAS (cumulative capture of 4.7 per trap in blocks that received no pre-bloom insecticides, or 5.5 per trap in blocks receiving pre-bloom insecticides) and ABLM (cumulative capture of 13 moths per trap from silver tip through late pink).

Patterns of pear thrips activity in the northeastern United States, 1990-1992

Pear thrips, Taeniothrips inconsequens, activity and damage in forest stands of sugar maple (Acer saccharum Marsh.) was monitored in 18 states over a three-year period (1990–92). New state records were recorded in southern and mid-western states. In 1990, thrips activity was greatest; damage to maple foliage was related to thrips activity during and just after maple buds opened. In subsequent years, thrips activity was lower and damage less apparent.