Which perimeter practice is effective for occasional invaders, and why might some treatments fail?

Which perimeter practice is effective for occasional invaders, and why might some treatments fail?

• A. Ignoring exterior gaps
• B. Spraying only the interior walls
• C. Using only baits indoors
• D. Treating cracks/openings around windows and between foundation and siding

Answer: (D)

The key idea here is stopping occasional invaders at their entry points with a perimeter barrier. Treating cracks and openings around windows and where the foundation meets siding blocks the main routes pests use to get inside, giving you a preventive shield that reduces interior activity. This approach is best because it targets the source of the problem—pests entering from outside—so interior treatments aren’t the only line of defense. If you ignore exterior gaps, spray only interior walls, or rely solely on indoor baits, you miss the entry points and re-infestation is likely as soon as pests find another way in or come back from outside. Exterior crack-and-opening work, combined with an exterior barrier, is especially effective for occasional invaders because they respond to entry points more than to interior-only measures.

The key idea here is stopping occasional invaders at their entry points with a perimeter barrier. Treating cracks and openings around windows and where the foundation meets siding blocks the main routes pests use to get inside, giving you a preventive shield that reduces interior activity. This approach is best because it targets the source of the problem—pests entering from outside—so interior treatments aren’t the only line of defense. If you ignore exterior gaps, spray only interior walls, or rely solely on indoor baits, you miss the entry points and re-infestation is likely as soon as pests find another way in or come back from outside. Exterior crack-and-opening work, combined with an exterior barrier, is especially effective for occasional invaders because they respond to entry points more than to interior-only measures.