The UK Phenology Network reports on the first flowering dates of allergenic plants. They offer an analysis of the national mean first flowering dates for four grasses (Meadow Foxtail, Cocksfoot, Timothy and Yorkshire Fog) and three trees (Silver Birch, Pedunculate Oak and Sessile Oak) up to 2024.
Nature’s Calander (naturescalendar.woodlandtrust.org.uk), the UK’s phenology network, now has more than two decades of contemporary data on most of its recorded events. These include popular events, such as tree leafing and the flowering of woodland plant, but also the first-flowering dates of a number of allergenic species.