annual bluegrass

By Dominic Petrella

The University of Minnesota Turfgrass Science Team has partnered with the Minnesota Golf Course Superintendents Association (MGCSA) to perform on-site research determined by the members themselves. As part of this project, we conducted a study at the Rush Creek Golf Club in 2017. We examined the following research question: Will early spring paclobutrazol applications eliminate annual bluegrass?

Paclobutrazol is a plant growth regulator used to inhibit annual bluegrass (Poa annua) growth.  This suppression makes the desirable turfgrasses more competitive, allowing them to crowd out the weedy annual bluegrass.

When warm February weather occurs in Minnesota, it can cause damage to annual bluegrass.  We partnered with a MGCSA member to investigate whether warm February temperatures, in combination with an application of paclobutrazol, would give us the opportunity to push annual bluegrass over the edge and eliminate it from putting surfaces.

Research questions

The University of Minnesota Turfgrass Science Team has partnered with the Minnesota Golf Course Superintendents Association (MGCSA) to perform on-site research determined by the members themselves. As part of this project, we conducted a study at the Medina Country Club and the Les Bolstad Golf Course in 2017. We examined the following research question: Will installing covers during a February warm-up reduce the risk of injury to annual bluegrass due to deacclimation?

Plants that overwinter undergo physiological changes to acclimate to cold temperatures, allowing them to survive until spring.  However, when warm temperatures occur in winter, cold hardiness gained through acclimation can be lost, a process called deacclimation.