Phenology: Reading nature's seasonal calendar

"Phenology is the study of seasonal changes in plants and animals from year to year, such as when flowers bloom, birds nest or insects emerge. Derived from the Greek word "phaino," meaning "to show" or "to appear," phenology helps us observe and understand how the natural world responds to climate and environmental changes over time. Gardeners, farmers, naturalists and scientists have long relied on phenology to guide decision-making."

"Phenology is all about timing. For gardeners and farmers, seasonal changes signal the best times to plant, prune, fertilize and harvest. Shifts in temperature - warmer or cooler - can move these events weeks earlier or later on the calendar. Phenology also plays a critical role in pest and disease management. By tracking seasonal patterns, gardeners can better time interventions such as applying beneficial nematodes or setting pheromone traps for wasps."

"These seasonal patterns are especially vital for pollinators. When the timing is right, pollinators arrive just as the plants they rely on for nectar and pollen are blooming. But when that timing is off, the results can be harmful. For example, if native bees emerge before their host plants bloom, their survival is at risk. Similarly, if native milkweed doesn't go dormant in time to prompt monarch butterflies to migrate to overwintering sites, the monarchs may be endangered."

Phenology studies annual seasonal changes in plants and animals, such as flowering, nesting and insect emergence, and derives from the Greek phaino meaning "to show" or "to appear". It links observable biological timing to climate and environmental change. Practitioners including gardeners, farmers, naturalists and scientists use phenological cues to schedule planting, pruning, fertilizing and harvesting. Temperature shifts can advance or delay these events by weeks, affecting pest and disease management and the timing of interventions like applying beneficial nematodes or setting pheromone traps. Phenological mismatches can harm pollinators and migratory species, for example when bees emerge before host plants bloom or milkweed fails to cue monarch migration.

Read at The Mercury News