Dale J. Bremer

Evaluating Small Unmanned Aerial Systems for Detecting Drought Stress on Turfgrass

This study was conducted to evaluate early detection ability of small unmanned aerial systems (sUAS) technology for drought stress on turfgrass. Certain reflectances collected by sUAS and a handheld device declined more in less irrigated treatments before drought stress was evident in visual quality rating (VQ) and percentage green cover (PGC). The near infrared (NIR) band and GreenBlue vegetation index performed the best consistently for drought stress prediction among the other vegetation indices (VI) or bands from sUAS. Results indicate using ultra-high resolution remote sensing with sUAS can detect drought stress as well as, if not better than, a handheld device before it is visible to the human eye, and may provide valuable evidence for irrigation management in turfgrass.

Performance and Recovery of Turfgrasses Subjected to Drought and Traffic Stresses

This study is an effort to determine effects of drought and traffic in turfgrasses. During a 41-day summer drought in 2015 and 2016, warm-season (C4) grasses were more affected by traffic than cool-season (C3) grasses when percent green cover and turf quality were measured. This was because the non-trafficked plots in C4 grasses maintained higher percent green cover and turf quality throughout the drought due to better drought-stress tolerance than the C3 grasses. Regardless of traffic treatment or mowing height, C4 grasses maintained higher percent green cover and visual turf quality than C3 grasses during drought and recovery periods. There was a larger separation between traffic treatments within the higher (rough) height compared to the lower (fairway) height. Overall, traffic application during a drought will have a negative and accelerated impact on the above-ground portion of turfgrass, which will vary due to turf species and mowing height.

Small Unmanned Aircraft Systems Detect Turfgrass Drought

Kansas State University is evaluating the ability of using small unmanned aircraft systems (UAS) to detect drought stress in turfgrass. Their research indicates high resolution remote sensing with small UAS can detect drought stress before it is visible to the human eye. Preliminary measurements of a golf course revealed interesting differences in fairways, tees, and greens between summer and fall seasons. Additional research will be conducted in 2016.

Influence of Glyphosate Timings on Conversion of Golf Course Rough from Tall Fescue to ‘Sharps Improved II’ Buffalograss

All treatments, except the control that received no glyphosate application, resulted in acceptable buffalograss establishment (>90% buffalograss green cover) by 70 days after seeding (DAS). However, any treatment not sprayed prior to seeding date or that received a 7 DAS application lagged behind in establishment for 6 weeks after seeding.