April 9, 2020. With just a couple of clicks, you can help the USA National Phenology Network’s Track a Lilac citizen science project. Phenologists consider lilacs to be a crucial tool in tracking the Earth’s warming. Phenology is the science of measuring our climate with repeating biological events, such as the blooming of lilacs.
Since lilacs bloom only in response to temperature, they have been used to measure our changing climate for more than 50 years. The common lilac is considered to be an ‘indicator plant,’ one that is sensitive to temperatures, rather than seasonally changing light.
According to the USA National Phenology Network (NPN), spring is happening about 2.5 days earlier every decade. Be a part of this important project, and help track the lilacs you love in your yard and neighborhood.
This helpful 2-minute PBS video shows you more info.
Tell them where you are, and what you see on the lilac.
Enter your zip code, and if you see breaking leaf buds, open flowers or full flowering lilacs. See the samples below. Scroll down to see the simple form.
Breaking leaf buds
In at least 3 locations on the plant, a breaking leaf bud is visible. A leaf bud is considered “breaking” once the widest part of the newly emerging leaf has grown beyond the ends of its opening winter bud scales, but before it has fully emerged to expose the leaf stalk (petiole) or leaf base. The leaf is distinguished by its prominent midrib and veins.
For the whole plant, at least half (50%) of the flower clusters have at least one open fresh flower. The lilac flower cluster is a grouping of many, small individual flowers.
For the whole plant, virtually all (95-100%) of the flower clusters no longer have any unopened flowers, but many of the flowers are still fresh and have not withered.