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

WP1: Field trials comparing robotic and manual mowing of pure stands of colonial bentgrass (CB), red fescue (RF) and Kentucky bluegrass (KB) on fairways, and perennial ryegrass (PR), RF and KB on semi-rough, were established at NIBIO Landvik, Norway, in spring 2020. Robotic mowers (Husqvarna 550) on fairway (mowing height 15 mm) and semi-rough (mowing height 35 mm) were installed in August 2020. Despite a winter with little snow cover and deeply frozen soil, there was no serious winter damage and no plots had to be reseeded. A substudy on encroachment by broadleaf weeds was established in May 2021, with dandelion, white clover and broadleaf plantain planted in fairway and semirough subplots. Turfgrass quality and associated features in robot-mown plots were compared with control plots mown with a cylinder mower on fairway and a rotary mower on semi-rough AprilOctober 2021. Results showed less disease in robot-mown plots, notably microdochium patch in CB on fairway and red thread in PR in semi-rough. However, more white clover was observed in robot-mown plots, notably in PR in semi-rough. Overall turfgrass quality was high with manual and robotic mowing on fairway and semi-rough, but in late summer there was a tendency for lower quality on robot-mown semi-rough plots (RF, PR).

WP2: The N fertiliser effect of returning clippings in robotic vs. manual mowing was studied on fairway seeded with a mixture of KB, CB and EF. Robotic vs. manual mowing was compared August-November 2020 and April-November 2021. N rates of 0, 3, 6, 9 and 12 g/m2/yr, each split into six equal inputs, were applied over the season. For both manual and robotic mowing, returning clippings increased clipping yield compared with clippings removal. The N concentration in clippings was higher in spring and early summer than in late summer and autumn. Turfgrass quality assessments gave high ratings for robotic and manual mowing.

WP3: Large-scale demonstration trials with robotic and cylinder mowers on fairways and rotary mowers on semi-roughs were laid out at Bærheim GC (Norway), Grenå GC (Denmark), Jönköping GC (Sweden), Ness GC (Iceland) and Hirsala GC (Finland). Turfgrass quality, broadleaf weed cover and energy use were recorded monthly from May to October by the course manager on all five courses. Turfgrass quality in robot-mown plots was mostly similar to manually mown plots on fairways, but better than manually mown plots on semi-roughs.

Contact
Karin J. Hesselsøe

Karin J. Hesselsøe, Norwegian Institute for Bioeconomy Research (NIBIO), Department for Urban Greening and Vegetation Ecology, Turfgrass Research Group, Landvik, Reddalsveien 215, 4886 Grimstad, Phone:+47 41396851. E-mail:karin.hesselsoe@nibio.no

FACTS
Category: Water, nutrients, construction
Status: Ongoing
Project period: 2020 - 2023

Fundings (kSEK)

 

2020

2021

2022

2023

Total

STERF

250

326

336

160

1072

Husqvarna

952

376

396

304

2028

Participating golf courses

81

83

83

0

250

Total

1283

785

818

464

3350

 

Project objectives

  • To generate and disseminate knowledge about implications for turfgrass quality, fertiliser requirement, weed encroachment and susceptibility to various diseases of switching from conventional manual mowers to robotic mowers on fairways and semi-roughs with grass species typical for Nordic golf courses.

  • To generate and disseminate knowledge about implications for labour and energy use, CO2-emissions and soil compaction of switching from conventional manual mowers to robotic mowers on fairways and semi-roughs with grass species typical for Nordic golf courses.

  • To generate and disseminate knowledge about implications for player and greenkeeper satisfaction of switching from conventional manual mowers to robotic mowers on fairways and semi-roughs with grass species typical for Nordic golf courses.