Impact of snow manipulation on overwintering disease and frost damage across pasture grass species

TL;DR

Snow manipulation reduces overwintering diseases in pasture grasses but can increase frost damage in some species.

Contribution

The study identifies species-specific responses to snow manipulation for disease and frost management in pastures.

Findings

Snow manipulation reduced Mild-T days and disease severity, especially in timothy.

Perennial ryegrass showed severe frost damage despite reduced snow mold.

Orchardgrass maintained productivity through strong regrowth after overwintering losses.

Abstract

Snow manipulation regulates soil temperature, reducing overwintering diseases and supporting pasture growth, though it has a limited effect on supporting grass growth. This study assessed the snow manipulation effects on overwintering damage and disease control in timothy (TY), orchardgrass (OG), and perennial ryegrass (PR). Snow manipulation decreased Mild-T days (soil temperatures near 0 °C), which correlated with reduces disease severity, particularly in TY. In plots with < 20 consecutive Mild-T days, maximum disease severity was lowest in TY (0.13) compared with that in OG (1.78) and PR (1.63). However, total overwintering damage also depended on disease and frost resistance. Although snow mold reduction did not consistently decrease damage, PR exhibited severe frost damage, making it highly vulnerable to snow manipulation. Contrastingly, OG compensated for overwintering losses with strong regrowth, maintaining similar dry matter yield. Snow manipulation effectively controls overwintering diseases but may raise frost damage in less cold-resistant species. TY showed the greatest adaptability, PR was highly frost-susceptible, and OG maintained productivity despite overwinter losses. These findings highlight the need to consider disease and frost resistance when using snow manipulation for disease control.

The online version contains supplementary material available at 10.1038/s41598-025-21885-8.

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