PHYS FACTORS AND RATINGS = Physical Factors and Ratings
These are factors which limit productivity on a local rather than a broad basis. Examples of physical factors include flooding, salinity, sand and gravel pockets. They are expressed in terms of a percentage of potential production. There can be a maximum of three miscellaneous factor deductions per soil area. In this sample field sheet two physical factor deductions have been applied. These are as follows: PSA- the symbol for poor drainage and salinity and SD which is the symbol for sand. On this sample sheet four percent of the area has salinity which is reducing the crop yield to nothing. The deduction is applied by multiplying the master rating by .96 which is the same thing as subtracting 4% from the master rating. Similarly on this sample field sheet there is a SD 80 discount. The potential productivity rating is being reduced by twenty percent for the presence of pockets of sand found throughout the cultivated soil area. For instance: 40% of the area of the field could be affected by the sand reducing crop yields over the affected area by 50%. 40% x 50% = 20% reduction.

Abbreviations:
BE = Bedrock
BO = Solidization + Burnout
F = Flooding
FR = Frost
G = Gravel Pockets
LT = Loose Top
PD = Poor Internal Drainage
PDT = Poor Drainage & Peat
POD = Podsolization
PSA = Poor Drainage & Salinity
PT = Peat
SA = Salinity
SD = Sand Pockets
SOL = Solidization
SST = Sub-Surface Texture


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