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Track a Lilac invites viewers to find a nearby lilac and report whether they see leaves or flowers on their plant. The data contributes to a national database that will be used by researchers to better understand the timing of lilac leafing and blooming across the country. Participants follow three simple steps: show us where you are, tell us what you see on your lilac, and report your observation.

Lilacs are broadly distributed across the nation, are quite common in backyards, and are easy to recognize. With a simple datasheet, members of the public can take part in this citizen science effort to track the phenological activity of lilacs all across the country.

These observations are part of an effort over 60 years in the making! Phenology observers have been tracking lilacs since the 1950s as part of a research project to understand how plants respond to environmental change. These observations have enabled the creation of the USA-NPN's Spring Index models, which predict leafing and flowering in lilacs. These models and associated maps can be used to predict the activity of early season plants at locations across the country and see how the timing of spring activity in a particular year compares to a long-term average.

Researcher Bios

Track a Lilac Scientists

The data and resources contributed to Track a Lilac and Nature's Notebook are used by scientists around the globe as well as by many members of the USA National Phenology Network staff. The many scientific publications that have resulted from the incoming data are curated on the USA-NPN website and are summarized in a public-friendly format in the USA-NPN Publication Summaries. Nearly all members of the USA-NPN staff have participated in scientific analyses using these data as well.


Project URLs



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