Evaluating Cut Quality Testing Methods for Consumer Lawn Tractors.

Tests were designed to measure the distribution of the clippings from the side discharge unit as well as determine if excess clippings accumulated under the mowing deck after cutting in a mulching or bagging set-up. Ideally the clippings are distributed such that a minimum residual is left on top of the turfgrass and those that remain are adequately distributed without clumps or windrows. All the tests were conducted with healthy overseeded ryegrass in Raleigh, NC and Bradenton, FL. Only dry turfgrass surfaces were used for testing. Three mower replicates were tested for four mower models in our initial testing. All mower set-up was according to the Operating Manual provided with each mower. All mowers and mowing components were labeled so that they could be tracked and used on the same mower for the duration of the study. Mowers were driven over a set course for each test mode with one operator. Engine and ground speed were monitored during the study. Fresh clippings were collected from the turfgrass surface in previously determined locations and weighed to characterize distribution. The overall clipping throw distance was estimated from the point of discharge. Turfgrass visual ratings were made 24 hours after mowing by two experienced turfgrass professionals. Data collected included an evaluation of clipping distribution, windrowing, and clumping, as well as the presence of swirl marks and uncut grass blades. All ratings were made using a 1 (poor) to 9 (excellent) scale. Bag capacity and square footage covered were measured during bagging operations. In addition to weighing clippings and visual ratings, trials were run using digital image analysis (DIA) as a way to better document clipping dispersal. All trial data was subject to ANOVA using standard statistical analysis techniques. Testing methods used in these studies were capable of separating classification variables.