Are you eagerly waiting for spring? The first daffodils to bloom … chickadee song … snow drops and crocuses?

You’re not alone! Probably since the dawn of civilization, winter-weary folks have counted the days for green sprouts and blossoming flowers. Some of those folks kept detailed notes on what they saw and when.

Two especially avid record-keepers lived nearly a century apart in different regions of America: Henry David Thoreau, author of Walden, and Aldo Leopold, author of Sand County Almanac.

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Thoreau chronicled the arrival of spring around and near his beloved Walden Pond in Concord, Mass., during the mid-1800s. Leopold kept notes on plant blooming dates in Sand County in central Wisconsin in the mid-1900s, something volunteers still do many years after his death.

Thoreau and Leopold practiced phenology, the study of plant and animal life cycles and interactions.

As it turns out, Thoreau and Leopold’s observations are more than dusty historical records. A group of scientists is using their records to compare the differences in flowering times of native plants. This will shed light on how plants are responding to climate change.

The recently published study, “Record-Breaking Early Flowering in the Eastern United States,” used data collected by the two nature writers. The results were clear:  Many plants are blooming considerably earlier than in Thoreau’s and Leopold’s times.

For example, Boston University biology professor Richard’s Primack’s team visited Thoreau’s sites and learned that in an average year, flowers bloom about 11 days earlier than in Thoreau's time. In Wisconsin, biologist Stanley Temple chronicled similar findings.

The authors of the study are concerned that “ecological mismatches” may result – that is, trees and shrubs may bloom before their pollinators emerge, or be damaged by frost, reducing their ability to bear fruit or set seed. Migratory birds returning from the tropics, like warblers and vireos, may arrive after their food, an early flush of leaf-eating caterpillars, has begun to decline.

The field of phenology requires more study through the country. And you can help!

A new program known as “Nature’s Notebook,” sponsored by the USA-National Phenology Association, invites citizen-scientists to observe the natural world and submit findings via the internet to a national database. New Jersey’s forests, preserved open spaces and backyards abound with species whose phenology can be recorded by citizen observers.

Here are four easy steps you can take:

  • Learn about plants and animals in your area;
  • Learn how to observe – what to look for and when;
  • Create an account and password with USA-NPN; and
  • Log in to Nature’s Notebook to register your data.

Nature’s Notebook contributors already include backyard gardeners in Maryland, high school students tracking flowers in Arizona, farmers tracking the timing of wheat productions in the Midwest, and Boys’ and Girls’ Clubs building and monitoring phenology gardens in California.

For more information about the Nature’s Notebook program, and phenology in general, go to the USA-NPN website at To read the study, “Record-Breaking Early Flowering in the Eastern United States,” go to

And to learn more about preserving New Jersey’s land and natural resources, visit the New Jersey Conservation Foundation website at or contact me at