Impact of Dry-injection Cultivation to Maintain Soil Physical Properties for an Ultradwarf Bermudagrass Putting Green

Abstract

<jats:p>Traditional hollow-tine (HT) aerification programs can cause substantial damage to the putting green surface resulting in prolonged recovery. Despite the growing interest in new and alternative aerification technology, there is a lack of information in the literature comparing new or alternative technology with traditional methods on ultradwarf bermudagrass [<jats:italic>Cynodon dactylon</jats:italic> (L.) Pers. × <jats:italic>C. transvaalensis</jats:italic> (Burtt-Davy)] putting greens. Therefore, the objective of this research was to determine the best combination of dry-injection (DI) cultivation technology with modified traditional HT aerification programs to achieve minimal surface disruption without a compromise in soil physical properties. Research was conducted at the Mississippi State University golf course practice putting green from 1 June to 31 Aug. 2014 and 2015. Treatments included two HT sizes (0.6 and 1.3 cm diameter), various DI cultivation frequencies applied with a DryJect 4800, and a noncultivated control. The HT 1.3 cm diameter tine size had 76% greater water infiltration (7.6 cm depth) compared with the DI + HT 0.6 cm diameter tine size treatment. However, DI + HT 0.6 cm diameter tine size had greater water infiltration at the 10.1 cm depth than the noncultivated control. Results suggest a need for an annual HT aerification event due to reduced water infiltration and increased volumetric water content (VWC) in the noncultivated control treatment. It can be concluded that DI would be best used in combination with HT 1.3 or 0.6 cm diameter tine sizes to improve soil physical properties; however, the DI + HT 0.6 cm diameter tine size treatment resulted in minimum surface disruption while still improving soil physical properties compared with the noncultivated control.</jats:p>

Short‐term effects of alternative cultivation practices on putting green infiltration rates

“…It should be noted that the tine spacing for HTC was much closer than SIC which resulted in approximately seven and five holes within the inner ring of the infiltrometer for HTC and SIC, respectively. Craft et al (2016) also reported that SIC applied five times per year did not improve the infiltration rate compared to nontreated control. This lack of effect is possibly due to a relatively small area of impact and no alleviation of surface compaction.…”

“…The process was repeated until two consecutive readings were the same. Surface firmness was measured using a handheld firmness meter (Field Scout TruFirm; Spectrum Technologies) which records the penetration depth of a falling plunger as it hits a surface (Craft et al, 2016;Dickson et al, 2017). Firmness was measured following the single drop of the plunger on nine points across a grid and averaged within each plot for subsequent analyses.…”

“…F I G U R E 1 Position of infiltrometer ring for measuring infiltration after air-injection cultivation (AIC) where infiltration measured directly at the injection hole (a), adjacent to injection hole (b), and midway between injection holes (c) scale of 0 to 100% (100% = holes fully recovered; Craft et al, 2016). Recovery was rated 7, 14, 21, and 28 DACE.…”

“…Cultivation practices such as core aerification, vertical mowing, and topdressing are commonly used to manage soil OM or compaction. Core aerification that removes soil cores is typically considered the most effective method for physical removal of OM, reducing compaction, and increasing infiltration rates, increasing surface aeration and rooting (Craft et al, 2016;McCarty et al, 2007;Rowland et al, 2009; Crop Science Sorokovsky et al, 2007). Typical core aerification practices can reduce the aesthetic and functional aspects of a putting green, temporarily causing reduced revenue or distaste within the course membership.…”

“…Air-injection cultivation injects high pressurized compressed air to the depth of 15 to 30 cm using the Air2G2 (GT AIRINJECT Inc.). These alternative cultivation practices have been reported to increase infiltration and drainage or reduce soil compaction with minimal surface disruption (Craft et al, 2016;Dickson et al, 2017;Green et al, 2001). A considerable amount of research has been conducted to compare the effect of traditional cultivation practices on soil physical properties (Bunnell et al, 2001;McCarty et al, 2007;Rowland et al, 2009;Sorokovsky et al, 2007), whereas only a few studies have been conducted to evaluate the effect of alternative cultivation practices (e.g., AIC and SIC).…”