Better turfgrass survival in a changing winter climate


WP1. In late November 2011 and 2012, six turfgrasses used on golf greens were tested for deacclimation after 6 or 12 days at 10˚C in weak light. The ranking of freezing tolerance (LT50) was consistent:  creeping bentgrass (mixture of ‘Penn A1’, ‘Penn G6’ and ‘Independence’) > velvet bentgrass ‘Villa’ > chewings fescue ‘Musica’ > slender creeping red fescue ‘Viktorka’ > colonial bentgrass ‘AberRoyal’ > and annual bluegrass. Creeping bentgrass and annual bluegrass dehardened more than the other species, but creeping bentgrass was still the most frost-tolerant species after deacclimation. None of the species was able to reharden at 2 °C for 23 days after 12-d dehardening to their original freezing tolerance. The inability to reharden was positively correlated with induction of elongation growth.

WP2. Strong creeping red fescue, Kentucky bluegrass, chewings fescue and perennial ryegrass were grown on fairway with a high or low watertable in autumn to evaluate effects of pure drainage on winter survival. Plants were collected from the field and tested for freezing tolerance three times during winter 2011-12 and 2012-13. In the first winter, the plants were more  freezing tolerant on 30 January than on 12 December or 19 March. In the second winter, with ice under snow from the end of December to the end of March, the freezing tolerance declined from 7 December throughout the winter. There was no effect of high watertable on acclimation of the plants, but fescues survived better in drained soil during the second winter. There was no relationship between LT50 values and crown moisture.

WP3. Six green grass species (as in WP1) had different winter microclimate: natural conditions, ice encasement (IE), plastic cover or plastic cover and airfilled mat. Several times during two winters, the survival of the grasses was measured as regrowth. During both years the natural conditions, with snow cover, gave the best winter survival. Only IE gave substantial damage. Velvet bentgrass had superior tolerance to ice encasement. Colonial bentgrass responded negatively to protective covers due to snow mould (unsprayed!), and was also weak against IE. Annual bluegrass showed the lowest tolerance to IE and was the only species that benefited from protective covers.

Full-scale experiments on three golf courses over three winters in Finland, Sweden and Norway concluded that plastic covers, which prevented water intrusion, protected the greens from damage in winters with a high risk of ice encasement.

As part of the project, an international seminar, “Turf Winter Survival”, was arranged at Gjøvik, Norway (11-12 November) with 56 delegates from 8 countries (Photos 1,2). The main results, all presentations and a book of abstracts are available on the STERF website. The seminar received publicity on several websites.

Category: Overwintering
Status: Finished
Project period: June 2011 – December 2014

Fundings (kSEK)














1 008

Other sources:

1 028

1 315



3 294


1 373

1 584

1 263

1 081

4 220

Project objectives

Principal objective: To reduce winter damage to grasses used for golf courses, recreational areas and pastures through better understanding of dehardening reactions and appropriate management in a wetter and less stable winter climate.

Subprojects (SP):

  • To determine the deacclimation susceptibility and reacclimation potential of five species commonly used on greens under controlled conditions (SP1);
  • To monitor cold hardiness levels from 15 Dec. to 1 May of four species growing on a fairway with low or high watertable and relate this to temperature, moisture content and carbohydrate content in turfgrass crown tissue (SP2);
  • To assess the impact of turfgrass covers, snow removal and increasing duration of ice encasement on the survival of five turfgrass species under green conditions (SP3).

Project participants

Tatsiana Espevig


Norwegian Institute for Bioeconomy (NIBIO), Department for Urban Greening and Environmental Technology, Turfgrass Research Group, Landvik, Reddalsveien 215, 4886 Grimstad, Norway.

+47 406 23 778

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