Select the layer that contains the soil areas.

Soil Production Factors

•Soil production factors can be indicated in one of two different ways:

oInclude a section in the advanced layer settings of the soils layer titled [Prod Factor] and list there the productivity factor for each soil type in the format "CbA=0.99"

oOr include a field named "Prod Factor" in the soils layer's layer format. And then populate this field for every feature with the production factor. Ex. "0.99".