Convert Fwys to CB to Rdc Inputs

bensulide will suppress true winter annual recruits. Post-emergent herbicides are available, and many have been shown to be safe on CB however, they have not received widespread interest due to potential risk of CB injury and cost. Products such as Velocity, Prograss EC and Xonerate have all demonstrated effective annual bluegrass control. Recently, a new selective herbicide was developed for annual bluegrass control, Methiolzolin (PoaCure). This selective herbicide has both pre- and post-emergence activity that is remarkably slow and often allows for seamless Methodical reduction of annual bluegrass in fairways will routinely leave voids that allow seeding of CB to be effective. The Summer presents an ideal time to seed CB as day lengths are at their maximum to promote establishment without competition from annual bluegrass (Brede, 2006; Bauer et al., 2012; Klein, 2021). Creeping bentgrass can be slit-seeded into void areas at rates of 2-3 lbs/1000 square feet for most effective establishment, followed by applications of nitrogen fertilizer up to 0.5 lbs/1000 square feet. Irrigation can be applied routinely in small amounts to keep seeded areas moist until establishment. The benefits of this approach are that course closure and drastic disruption practices are not required. However, there are several obstacles that make this approach less than ideal. Communication Established turf, even managed into a stressed state, will always have an advantage over seedlings (Cattani & Nowak, 2001). Stressed playing surfaces with large voids can disrupt play and be undesirable for golfers. The golfer must cope with several years of this sub optimal playability, and one must assess if golfers will accept these conditions to support long-term payoff. Therefore, an alternative option that intentionally disrupts play for less time to reset the desirable CB population might be a preferrable long-term solution. Eradication “Reset” Approach An eradication strategy uses a non-selective vegetation control strategy that eliminates the existing stand of turfgrass and re-establishes the fairways by seeding new desirable CB varieties. Recently, this method was used and well-documented by John Hoyle of Corning Country Club. This method is a more aggressive derivative of processes studied previously (Bauer et al., 2012), and has a formula as described in several USGA Greens Section articles (USGA Green Section, 2018; Jacobs & Gross, 2019; Klein, 2021). transition from mostly AB to mostly CB. Introducing Creeping Bentgrass

the seedbank if a fumigant is available. Aggressive conversion programs are the most disruptive to golf play but allow for the most rapid conversion. Either conversion program must have persistent exclusion strategies to prevent recolonization of annual bluegrass or other less desirable species. Methodical Approach Ecology The methodical approach centers on shifting to new varieties without large-scale disruptive practices over a long period of time (5-7 years). As described in a variety of scenarios (Gaussoin & Branham, 1989; Reicher & Hardebeck, 2002; Dobie, 2020: Diehl et al., 2021) this process requires management alterations to purposely impose stress on the undesirable species providing a competitive advantage for CB. As annual bluegrass populations decline and leave voids, it is imperative to have seed at the ready for seeding of CB into the voids leftover. This is a long-term approach, requiring many years before the transition to CB fairways can be Alteration of routine cultural practices to favor CB requires a wholesale shift in ideology. Essentially, discipline is required to withhold inputs (water, nutrients and pesticides) that are required for optimum performance of annual bluegrass. Creeping bentgrass performs better under lower soil moisture, lower Nitrogen levels, and fewer pesticides than annual bluegrass (Laskowski, 2017). In addition, damage thresholds can be raised to allow certain pests (dollar spot, anthracnose, annual bluegrass weevil) to selectively kill annual undesirable species, thereby promoting population shifts to CB (Diehl et al., 2020). Plant Growth Regulators The scientific literature is awash with research conducted on the use of plant growth regulators for suppressing annual bluegrass. Specifically, the use of class B growth regulators (paclobutrazol, flurprimidol) can reduce annual bluegrass populations (Dobie, 2020; Diehl et al., 2021; Klein, 2021; Petelewicz & Orlinski, 2021) that will significantly aid in this methodical approach. Herbicides Herbicides are simply plant growth regulators applied at lethal rates. There are several selective pre- and post emergent herbicides available for annual bluegrass control in fairways, but be aware of restrictions when shifting to CB, as not all selective materials are labelled or safe for use on CB. Herbicides are essential tools in the early phase of the exclusionary strategy. Once a good stand of CB is established, late summer applications of preemergence herbicides such as considered a success. Change Culture

Converting Fairways to Creeping Bentgrass to Reduce Inputs

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