Which of the following describes a disadvantage of soil incorporation?

The choice that highlights a disadvantage of soil incorporation is that it requires additional machinery. Soil incorporation typically involves the use of specialized equipment to mix pesticides into the soil effectively. This requirement can increase operational costs due to the need for purchasing, maintaining, or renting additional machinery. Furthermore, the logistics of bringing in extra equipment can complicate the process and delay applications, making it a notable disadvantage compared to methods that might not require such machinery.

In contrast to this, while environmental runoff, impact on beneficial soil organisms, and ineffectiveness compared to foliar treatments can also present concerns in pest management, they are not defining characteristics of soil incorporation itself. Instead, those issues may pertain to broader concerns of pesticide application or specific pest control strategies, not exclusively to the method of soil incorporation.