Holyoke soils are nearly level to very steep and are on bedrock controlled hills, modified by glacial action. Slope ranges from 0 to 50 percent. The soils formed in a thin mantle of glacial till over bedrock. Some pedons have been modified by silty windblown deposits. The underlying bedrock is primarily basalt but includes red sandstone, conglomerate, or shale.
Rock outcrops range from few to many.
Mean annual temperature ranges from 47 to 54 degrees F., mean annual precipitation ranges from 40 to 50 inches, and the growing season ranges from 135 to 195 days. These are the Boonton , Branford , Broadbrook , Cheshire , Enfield , Haledon , Hartford , Ludlow , Manchester , Menlo , Narragansett , Watchaug , Wethersfield , Wilbraham , and Yalesville soils on nearby landscapes. All except Yalesville are very deep to bedrock. Boonton, Broadbrook, Cheshire, Narragansett, and Wethersfield soils are well drained associates. Branford, Enfield, Hartford, and Manchester soils are on outwash terraces and are underlain by stratified sand and gravel.