Horticulture Principles and Practices

gibberellic acid spray overcomes stunting and axillary bud suppression. Sour cherry
yellows is a common viral infection of cherries that is commercially controlled by the
application of gibberellic acid on a significant scale.
8.4 CHOOSING A PESTICIDE
8.4.1 STEPS IN THE DECISION-MAKING PROCESS
OF PEST CONTROL
The following are general steps that may be followed in the development and implementation
of a pest-control strategy (Figure 8–1). Depending on whether the pest problem
is new, as well as the experience of the person making the decisions, some of the
steps may be skipped.
1. Detection. A pest-control program always starts with a problem. The pest must
first be detected. The presence of a pest may be detected by visual observation of
the organism or the damage it causes. While certain pests can be identified from
a distance, some pests have hiding places (e.g., the underside of the leaf, under
stones, or under debris) and require the grower to make an effort to search at
close quarters. The key to successful pest control is early detection. It is
advisable, therefore, that the grower routinely inspect the plants and look for
pests and disease organisms known to be associated with the production
operation and those prevalent in the area.
2. Identification. When a problem has been observed, it is important to make a
positive identification of the insect or pathogen. Without knowing the organism
involved, no sound control measure can be developed. Trial and error is wasteful.
If the grower does not have the expertise to positively identify an insect or
disease organism, a sample of an infected plant or the organism itself should be
collected and sent to an appropriate identification center, such as the department
of agriculture at a land grant institution or the U.S. Department of Agriculture
(USDA) Extension Office. County extension agents should be consulted before
contacting the national office.
3. Biology and habits. An organism has a life cycle. In insects that undergo a
complete metamorphosis, there is a dramatic change from one stage of
Detection
Identification
FIGURE 8–1 Steps in the
decision-making process for
pesticide application.
Biology and Habits
Economic Importance
Choice of Method
Application
Evaluation
Record Keeping
8.4 Choosing a Pesticide 247