← GlossaryAgronomy
Disease pressure
How favourable current conditions are for turf disease — mostly a function of warm nights and long leaf wetness.
Most turf pathogens need the leaf to stay wet and the night to stay warm. A cool night dries the canopy and ends the infection window; a warm humid one extends it, and several in a row are what turn a spot into an outbreak.
Published models exist for specific diseases and are worth using where you have the inputs for them. A general pressure index is a prompt to walk the greens, not a spray recommendation, and anything that presents it as a recommendation is overselling.
What it means for a small course
Treat any index — ours included — as a reason to go and look. The decision to spray is made by a person standing on the green.