While uphill or rolling land is the most desirable, the degree of slope can also limit its suitability. The ideal site has a 4 to 8 percent slope. It may be difficult to operate machinery on slopes of more than 10 percent. Selecting a site for an orchard involves below ground considerations as well, primarily soil depth and soil texture. An old recommendation for a desirable orchard soil is that it be deep and well-drained.
Soil drainage is probably the most important factor in the longevity of an orchard.
This is because of the inherent inability of certain types of fruit trees to survive when planted in imperfectly drained soils. Apples are intermediate and pears can survive on the more poorly drained soils. One classification of soils is based upon the mineral part of soil and consists of four sizes of particles. Clay particles are the smallest, followed by silt, sand, and gravel. The USDA has devised another system of classifying soil particles.