Lilacs were used in the mid-twentieth century to study the effects of location and climate on plant phenology.Phenology is the study of the timing of a plant’s reproductive cycle, such as flowering.
Syringia vulgaris, common lilac plants, were distributed to volunteers in 1956, and they sent postcards to the project coordinator every year indicating when their plant first flowered. This allowed J.M. Caprio, the man who started the project, to study trends in flowering based on location.
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