ROBO -GOLF: Robotic mowers for better turf quality, reduced fertiliser cost and less use of fossil energy on golf course fairways and semi-roughs

Summary

In WP1 and WP2, field trials at NIBIO Landvik comparing robotic and manual mowing were continued from 2020 and 2021. A dry autumn 2021 combined with a very dry spring and summer 2022 affected the trial area severely, with dry spots and outbreaks of antracnose in some of the experimental plots, and white clover developed markedly in both manual and robotic mown plots, especially in the semi-rough and in Kentucky bluegrass in the fairway. Irrigation was done in spring and summer.

In WP1, turfgrass quality in the fairway plots of colonial bentgrass was significantly lower than for the other species (regardless of mowing system). From June to August less white clover was observed in the robotic mown fairway plots compared with the manual mown plots. In the semi-rough the situation was the opposite with more white clover in the robotic mown plots. Lower ratings of turfgrass quality in the robotic mown semi-rough were explained by the higher coverage of white clover, most obviously in perennial ryegrass. In September root length and thatch accumulation were measured in sandplots in the fairway trial. No differences between robotic and manual mowing were found here.

In WP2, the N fertiliser effect of return of clippings at robotic vs. manual mowing showed a trend for higher quality with robotic mowing, but the difference from manual mowing with return of clippings was not significant. In both mowing systems and at all fertiliser levels, return of clippings gave significantly higher turfgrass quality compared with when clippings were removed. Regarding turfgrass quality and clipping yields, return of clippings corresponded to around 60 kg N/ha/year in this experiment. A trend for more white clover with robotic mowing on unfertilised fairway plots was observed, and confirmed the observations from WP1 semi-rough.

In WP3, demonstration trials at fairway and rough on five golf courses compared robotic and traditional mowers. Observations in 2022 from Bærheim GC, Norway, showed more dry spots and diseases in traditional mown fairway compared with robotic mown. At Hirsala GC in Finland, observations of less compaction resulted in improved drainage on the robotic mown areas compared with the traditional mown areas.

Fundings (kSEK)