To better control vector attraction, biosolids should be incorporated directly into the soil.  Not only does this aid in vector attraction, but also helps in bringing the material and the soils together and when combined, build a better soil tilth.   Sumas has a complete line of equipment for this process, including but not limited to discs, harrows and injectors.  Biosolids are historically applied following removal of a crop or before planting a cover crop. During this application period, incorporation with the use of a disc is the most common method, allowing the field to be worked prior to planting or before preparation of the next crop being planted has began.   Application to CRP ground does not allow the soil to be worked, this allows for a heavier application rate (aka. 5-10 year load), but still usually requires at a minimum harrowing of the materials into the existing vegetation.