Vineyard soils must be well drained. In the SSURGO database there are 8 capability classes with higher numbers indicating increasing restrictions to use. Much of the land in the county is highly suitable for agriculture and viticulture.
Capability classes are designated as follows Hutton (1972),
Class I - soils have few limitations that restrict their use.
Class II - soils have moderate limitations that reduce the choice of plants or that require moderate conservation practices
Class III - soils have severe limitations that reduse the choice of plants, require special conservation or both.
Class IV - soils have very severe limitations, require very careful management or both.
Class V and above - Very severe limitations not suitable for cropping.
Notes. Soil capability sub-clases where ignored. Increasing slope increases restriction classes. In this analysis the soil capability class was calculated from the restiction class on the lowest slope and incremented on the basis of slope class. Slopes were calculated from a 100m Digital Elevation Model.
| Slope Class % | Increment to capability
base class |
| 0- 3 |
0 |
| 3-8 |
1 |
| 8-15 |
2 |
| 15-24 |
3 |
| +24 |
4 |