1. Early Phenologists
USA-NPN NCO
December 2016

2. Photo: John Phelan via Wikimedia Commons
I’m going to tell you a story about a man named Henry. Henry was a great lover of the outdoors, and a natural history buff. He spent many years of his life walking around his hometown of Concord Massachusetts, looking carefully at the nature that surrounded him.

3. Photo: John Phelan via Wikimedia Commons
He would walk pathways, taking note of the different species of grasses, wildflowers, shrubs and trees.

4. Photo: John Phelan via Wikimedia Commons
He noticed how things changes through the seasons, and noticed when leaves emerged, when flowers appeared, and when leaves started to turn color and fall from the trees.

5. Photo: ptwo via Wikimedia Commons

6. Photo: victorgrigas via Wikimedia Commons
He took note of the dormancy of winter, and waited for the first signs of spring to emerge.

7. Letter from the Morgan Library & Museum, New York
Henry liked to write, and kept detailed records of the changes see saw around him. He wrote down all of this observations of nature, and other musings, in his journal each night. Perhaps by now some of you have guessed the identity of the famous Henry?

8. Photo of Henry David Thoreau from the National Portrait Gallery
The answer is Henry David Thoreau, one of our early phenologists. In 1860, Thoreau began to extract information on phenology from his journals, and compiled the information in charts.

9. Chart from the Morgan Library & Museum, New York
The charts showed observations of many individual species over a number of years, allowing a comparison of flowering times and other phenological changes from year to year.

10. 2012. Primack, R. B, Miller-Rushing, A.J
Flowering plants
7 day average
In 2003, Researcher Richard Primack from Boston University and Abe Miller-Rushing from the National Park Service learned about this dataset and recognized its importance. They were able to compare Thoreau’s observations from the 1850s at Walden pond to observations at the same location in recent years.
They found that, on average, the first flowering date for 34 of the most common species has shifted about 7 days earlier than they did in his time. There are a number of reasons for this, including the potential influence of the urban heat island in proximity to Walden Pond. However, the important thing to note is that without his valuable dataset, we would not have information about what happened in the past.
Here is a summary of that research:
2012. Primack, R. B, Miller-Rushing, A.J

11. Photo: FHWA via Wikimedia Commons
Why does this shift matter? If flowering times shift earlier, but the pollinators that these plants rely on do not, there can be mismatches in these relationships. Also, invasive species can gain an advantage, as we’ve seen with purple loosestrife, and invasive species in Concord. This species leafs out in warmer years, helping it get the pollinators and crowding out other native species.
One of the largest differences that Primack and Miller-Rushing found was how few native wildflower species were present compared to in Thoreau’s day.

12. Other early phenologists
Photos: Jefferson portrait by Rembrandt Peale, Powell images from the National Portrait Gallery, Washington, Aldo Leopold portrail from Aldo Leopold Foundation, Nina Leopold Bradley photo from Journal Sentinel files,
Leopold
Jefferson
Here are a few examples of early citizen scientists who paid careful attention to phenological happenings. Their reasons for doing this varied from curiosity, to documentation of travels, to understanding how best to tend to one’s land.
Thomas Jefferson – kept detailed records of crops at his home in Monticello
John Wesley Powell – explorer and soldier in the 1800s who mapped various geological features
Aldo Leopold and his daughter Nina Leopold Bradley kept detailed records at The Shack in Wisconsin of plant and animal phenology, including arrival times of migratory birds
Powell
Leopold-Bradley

13. Phenology Video by Climate Wisconsin (produced by the Wisconsin Educational Communications Board):

14. Follow in the footsteps of Thoreau…join us!
You too can become a citizen scientist. Join us in collecting phenology observations through Nature’s Notebook, and become part of the USA National Phenology Network.
Photo: Brian F Powell

15. Contact nco@usanpn.org
Questions?
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USA-NPN NCO
December 2016