Kentucky bluegrass (KBG) is the most widely used turfgrass in the United States, followed by bermudagrass. In Arizona, Kentucky bluegrass is best adapted to areas of high elevation of 5500 feet or above where it lasts all year long when managed properly. There are many Kentucky bluegrass turfs in Payson, the White Mountains, Flagstaff and higher elevation areas of the like. Kentucky bluegrass should not be used for bermudagrass overseeding.

Due to the dry climate in Arizona, we are fortunate that we do not have extreme disease pressures. We do have some minor leaf-spot problems in the fall and do have to a limited extent the circular patch diseases (necrotic ring spot and summer patch).

Necrotic ring spot causes circular patches of straw colored turf, usually with a green patch growing in the middle. Summer patch is distinguished by causing larger irregular patches where all the turf is usually killed.

We mainly have Mid-western (common) types of KBG which have been established in Arizona. These types have the narrow leaves which are very upright in growth stature, but do not form a very dense turf. The common types do grow back from drought damage from underground rhizomes more readily than most other types.

Listed in the accompanying table is a KBG variety classification scheme which is generally accepted nationwide. For general purpose lawns the common types are still acceptable. For shaded areas, select one of the northern latitude (compact) types. When selecting for high maintenance golf courses and high maintenance athletic fields, choose an "aggressive" type or a "mid-Atlantic" type variety.

What is the biggest mismanagement problem with KBG in Arizona? Thatch build-up and improper removal (time of year) and improper fertilization. More on that in a later issue.