Cover Story continued
These questions are beginning to be answered. Partnering with the Un-manned Systems Lab in the Mechanical Engineering department at Virginia Tech, our team has utilized UAVs to create high-resolution diseaseincidence maps. In spring 2016, disease-incidence maps were generated from five different bermudagrass golf course fairways infected with SDS. Aerial imagery was collected using an Iris+ (3D Robotics, Inc.) multirotor UAV, fitted with a HERO 3 (GoPro, Inc.) digital camera and PixHawk Mini mission planner. Aerial images were mosaicked using Agisoft PhotoScan 1.2.6 Professional. Spring dead spot ground-truth coordinates were obtained to geo-rectify the maps using the Raven Phoenix 300 w/Omnistar HP correction for sub-decimeter
spatial resolution. The fairways were rated visually and using digital image analysis to determine accuracy and to quantify disease incidence. In fall 2016, these disease incidence maps were used to make preventative fungicide applications to compare the efficacy of the fungicide Tebuconazole 3.4 F (tebuconazole, Quali-Pro) vs. the efficacy of Velista (penthiopyrad, Syngenta) vs. the site-specific application of Velista based on disease incidence. It is known that Velista is more expensive than Tebuconazole, but it has proven to be more effective in other SDS suppression trials. The applications were rated in spring 2017 and compared to non-treated plots. This research aims to translate remotely sensed data gathered through UAV imaging into usable information
for site-specific management of SDS on bermudagrass fairways. Additionally, exploration into the spatial distribution of SDS across fairways may enhance our understanding of the disease epidemiology by focusing on changes in microclimate and soil characteristics.
Predicting water deficiencies with unique sensors on drones Water usage receives much scrutiny in our industry because this limited resource drives global food and fiber production. Drought restrictions are first imposed to non-essential commodities, which includes recreational areas such as sports fields. This scrutiny has led sports turf managers to explore various methods to minimize their water usage, including
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Quadcopter equipped with a MicaSense Rededge sensor taking flight on a golf course fairway.
18 | VIRGINIA TURFGRASS JOURNAL July/August 2017 www.vaturf.org