ICE-BREAKER: Reducing the agronomic and economic impact of ice damage on golf courses and other grasslands


Winter kill due to ice encasement (IE), meltwater and subsequent problems with re-establishment is a severe problem on grasslands. This project is a joint effort by the golf industry and the Research Council of Norway, with the Norwegian Golf Federation as the project owner. It includes six work packages (WPs). WP 1-4 focus on how to prevent ice and water damage and WP 5-6 on how to re-establish winter-killed greens from seed.

In WP1, we will screen turfgrasses for tolerance to anoxia. On 3 December 2020, disc samples of 35 varieties representing seven species were taken from the SCANGREEN trial at Landvik, Norway, vacuum-sealed and incubated at 0.5°C to simulate IE. Samples will be taken out weekly after 5 to 13 weeks of anoxia and tiller survival wil be determined in the greenhouse.

In WP2, we will study the effect of direct ice cover, plastic sheets under the ice and timing of snow/ice removal on the survival of creeping bentgrass (CRB), annual bluegrass (AB) and red fecue (RF) greens at Apelsvoll, Norway.

WP3 includes four large-scale trials started in November 2020. Ventilation systems and ventilation frequencies will be tested on a total of 60 covered greens at four golf courses. Temperatures and CO2/O2 concentations will be monitored by wireless sensors installed under the covers.

WP4 focuses on the risk of pytoinhibition during the transition from IE to high light intensities/cold temperatures in spring. This work will be carried out in close collaboration with US researchers.

In preparation for WP5, CBG and RF greens were established from sod at Apelsvoll in June 2020. On 30 November 2020, the greens were covered by a 10 cm ice layer that will most likely cause 100% winter kill. At ice melt in spring 2021, toxic metabolites will be identified and their impact on germination and seedling growth determined in laboratory and field trials.

WP6 is a joint effort with the USGA project ‘Understanding Factors Associated with Successful Re-Establishment of Golf Course Putting Greens Following Winterkill’. The combined effect of temperature, light intensity and photoperiod on photosynthesis and growth of seedlings of four CBG varieties will be studied in parallel field trials in Minnesota (45°N), USA, and Landvik (58°N) and Tromsø (70°N), Norway, in spring 2021. A demo trial testing sowing methods and tarp materials for faster and most secure re-establishment of the same CRB varieties will be conducted on an ice-killed green in Central/Northern Sweden in collaboration with the Swedish Golf Federation.

Trygve S. Aamlid

Trygve S. Aamlid, NIBIO Department for Urban Greening and Vegetation Ecology, Turfgrass Research Group, Landvik, N-4886 Grimstad, Tel: + 47 90 52 83 78. E-mail:

Category: Overwintering
Status: Ongoing
Project period: 2020 - 2023

Fundings (kSEK)

  2020 2021 2022 2023 TOTAL
STERF 314 549 397 379 1639
Other sources 834 1195 1210 821 4060
Research Council of Norway 964 1666 1296 589 4515
TOTAL 2112 3410 2903 1789 10214

Project objectives

Primary objective
Better understanding of and improved strategies to prevent and repair damages caused by prolonged ice cover and melting water on golf courses and other grasslands.

Secondary objectives
1. Develop an efficient laboratory method for screening of grass cultivars and breeding lines, including a first evaluation of 30 new and/or commonly used cultivars of creeping bentgrass, red fescue (Festuca rubra L.), colonial bentgrass (Agrostis capillaris L.) and velvet bentgrass (Agrostis canina L.) for LDIE50 (Lethal Duration of Ice Encasement for 50% of plants)

2. Develop technology to predict ice damage and a decision-support system for when to remove the ice on golf greens by using wireless sensors to monitor temperature and O2/CO2 concentrations under ice. 

3. Determine to what extent an impermeable plastic barrier between the grass and the ice, including aeration pipes under the plastic, can protect grasslands from damage from long-lasting ice encasement and melting water. 

4. Elucidate if snow and ice removal from greens at different times during the winter can reduce ice and water damage.

5. Analyze to what extent impaired photosynthesis due to the formation Reactive Oxygen Species (ROS) upon re-exposure to aerobic conditions after ice melt or ice removal contribute to ice damage and if such damages can be alleviated by the use of shade cloths.

6. Identify toxic metabolites in the thatch/mat of young and old greens of various species and determine to what extent these inhibitors delay germination and/or seedling growth when reseeding golf greens after ice encasement.

7. Compare in large scale trials various sowing machines / sowing methods and explore the advantage of using primed seed of slowly vs. quickly germinating creeping bentgrass cultivars when reseeding greens that have been killed by ice encasement.