Page 23 - GreenMaster Winter 2023

winter injury
in the fall
Leaves left over winter can smother turf, resulting in bare patches and etiolation.
1. AERATION
Fall is a great time for aerating the turf. Core aeration helps alleviate soil compaction, promotes better water and nutrient infiltration, and encourages root growth. Note that core aeration, followed by sand topdressing, can sometimes create a layer of sand mixed with thatch which can then become hydrophobic. If you begin to see signs of hydrophobicity, use of a wetting agent can alleviate that issue. A new product to manage soil water repellency is the enzyme laccase, which could provide an organic approach to thatch management, although the performance of this product is yet to match the efficacy of commercial wetting agent (Sidhu et al. 2020).
2. OVERSEEDING
Overseeding after aeration allows new grass varieties to establish themselves before the onset of winter, enhancing the overall turf density and competitiveness against weeds. Selecting appropriate grass species and cultivars based on regional climate and course usage is crucial.
3. CULTIVAR SELECTION
Selecting the right grass cultivars is a fundamental step in preventing winter injury and snow mould. Different grass species and cultivars vary in their cold tolerance, disease resistance, and overall adaptability to winter conditions.
In a study across three Nordic countries over four years, the winter survival of creeping bentgrass was significantly better than Kentucky bluegrass, perennial ryegrass, and fine fescues when maintained at 3 mm and 5 mm height of cut (NIBIO, 2023). The relatively new varieties of creeping bentgrass ‘Matchplay’, ‘L- 93 XD’ and ‘777 Triple Seven’ performed the best regarding winter survival and disease resistance, closely followed by ‘Piranha’ and ‘Valderrama’. Of the Kentucky bluegrass cultivars, ‘Limousine’ produced the highest quality turf stand with improved density and winter-hardiness compared to ‘Professor’ and ‘Traction’.
4. FERTILIZATION
Late summer and early fall are ideal periods for fertilization, providing essential nutrients that support root growth and carbohydrate storage. Applying a balanced fertilizer with a
GreenMaster • CGSA • 23