Which factor could limit the effectiveness of spot fumigation?

Insufficient chemical concentration is a key factor that can limit the effectiveness of spot fumigation because it directly relates to the ability of the fumigant to penetrate and act on the target pests. In spot fumigation, the goal is to deliver a sufficient amount of fumigant to kill the pests in a specific area. If the concentration of the fumigant is too low, it may not reach the necessary levels required to be lethal to the pests present in the treatment area.

Adequate concentration is crucial because different pests have varying levels of resistance and susceptibility to fumigants. If the concentration is below the effective threshold, it may fail to eradicate the target pests, leading to incomplete control and potential reinfestation. Therefore, ensuring that the fumigant is present at the recommended concentration is essential for achieving successful pest management outcomes.

Other factors, such as pest mobility, short application time, and pest feeding habits, can certainly influence the overall effectiveness of a fumigation strategy. However, they do not affect the inherent potency of the fumigant as directly as insufficient chemical concentration does. Maintaining the correct concentration ensures that the fumigant is capable of doing its job effectively.