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Ministry of Agriculture, Food and Rural Affairs

How to Scout

Systematic monitoring of pest populations, weather conditions, plant health and disease symptoms are critical components of an IPM program.

Tools needed to monitor pests

  • a 16-20x hand lens
  • traps
  • collection bags and vials
  • field maps
  • flag tape
  • shovel or sturdy trowel
  • pocket knife
  • scouting forms and record sheets

Monitoring strategies

  • Review pest control calendars to know when certain pests will be active.
  • Learn to identify life stages and damage caused by diseases and pests.
  • Understand the biology and life cycle of pests and diseases.
  • Recognize beneficial insects, as well as harmless insects.
  • Use historical data to identify hot spots and previous problems.
  • Keep a field map and record the location of damage.
  • For each visit, record the stage of crop development, disease severity, population levels of insect pests and beneficials, and damage observed.
  • Keep a journal or log of rainfall amounts, daily highs and lows, and weather events.
  • Keep a record of pesticides applied and other control measures used.

Monitoring procedures

  • Monitor at least once a week and preferably twice a week during critical stages.
  • Monitor at approximately the same time each day and keep the light behind you.
  • Inspect plants in several areas across the field to get an accurate idea of pest pressure.
  • Stand back and look for patterns, such as patches or areas of poor plant growth or where colour is off.
  • Get close and examine fruit clusters, the underside of leaves and inside the canopy, etc.
  • Scout the edges of the field and interior of the field separately.
    Give special attention to border areas.

Sample collection involves the collection of data to represent the entire area being monitored.

  • Divide large areas into sample blocks.
  • Walk in a W or zig-zag pattern across the field to collect samples from a representative area.
  • Look away from the plant when you take samples of leaves and fruit, etc., otherwise you will tend to choose damaged leaves or fruit and bias the sample.
Sampling patterns Monitoring techniques Traps
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