Scouting Patterns 

Many pests scouted for are small or only found on a few plants out of hundreds. How a scout walks a block can determine whether the pest is found or not. There are three general methods for scouting: the rigid block method, the random walk method, and hot spot scouting.
    Rigid block scouting. The rigid block scouting method is the most thorough and, therefore, the most time consuming of the scouting methods. It is necessary to scout for the spruce spider mite, balsam woolly adelgid, rosette bud mite and hemlock rust mite.

    To scout a block using the rigid block scouting method, enter the block two to four rows from one corner. Record the row you start with on the scouting form so that on your next visit you will be able to start your survey one or two rows above or below this row. Walk the full length of the row, scanning from side to side up to five rows in each direction, depending on the size of the trees. To detect insect problems, it is necessary to see the top half of every tree and a full side of most trees. In a field of 3- to 5- foot trees, you may see five rows in each direction. In a field of 6- to 8-foot trees, you may see only three rows well. When you see a problem tree, go to it for a closer look, but return to your original row to continue through the field. When you reach the end of the row, step over six to ten rows as previously decided from tree size. Continue this pattern until you have covered the entire block.
    Random walk scouting. The random walk scouting method is less time consuming, but it does not give you the confidence you need to scout for most pests. It is appropriate for evaluating balsam twig aphid damage and weed populations. It would also serve as a method to evaluate the effectiveness of some pesticide treatments.

    To scout using the random walk scouting method, enter the block from one side, and circle through the block, trying to see into all areas of the field. Each time you scout the block, enter from a different side and take a different path. Walk toward any problem trees that can be seen from a distance.
    Hot spot scouting. Hot spot scouting is making repeated visits to a few small and specific areas of the field that tend to have early or recurring pest activity. Hot spot scouting can also be used to determine the size and stage of weeds, to time herbicide treatments, or to monitor the effects of weather on spider mite or rust mite populations. In some cases, frequent trips over several weeks may be necessary as a pest problem develops.
    Identify the "hot spot" through other scouting methods, and mark it with flagging and on a field map. Hot spot scouting can let you know if a treatment threshold is being approached, but use another scouting method to determine if the entire block requires a pesticide application.