Pawpaw, Asimina triloba, is a small understory tree very common in Appalachian forests. The fruit, prized by people and possums alike, has a custardy texture and flavor. The fruit, as well as the tree, is called Hoosier banana, at least in Indiana. Pawpaw is a member of the family Annonaceae, an important family of mainly tropical trees and shrubs. Pawpaw has many tropical characters, from its strange purple flowers to its broad, undissected leaves.

Here are some photos of the amazing flowers and young fruit of pawpaw. Click the pictures for really big images. The purple flower is especially glorious at full screen.

Phenology is the study of the timing of natural events. Phenology observers record the date and location of important seasonal events, such as bud burst, flowering, insect emergence and animal migration. Once a Victorian hobby, phenology has never been of much interest to Americans. The USA National Phenology Network (USA-NPN) aims to change that by creating a network of observers, from school children to scientists, to systematically collect and report phenology data.

By combining phenology data with short- and long-term climate and weather data, scientists are better able to track the impact of climate change on the natural world. The USA-NPN was launched in Spring 2008 as a collaboration between the US Geological Survey, the University of Arizona, the University of Wisconsin – Milwaukee and Project Budburst of the University Corporation for Atmospheric Research.

The creation of a national phenology network is not only of benefit to scientists. It can help connect people with nature in a way that is useful to our understanding of climate change. Because of the technical complexity of most science, it is more and more difficult for citizens to be scientists. In the 19th century, many scientific observations were made by hobbyists. The national phenology network offers the promise of restoring the tradition of the amateur scientist.

Phenological observations are easy to make. All you need is a calendar, notebook and perhaps a ruler. The USA-NPN is trying to systematize observations by creating several projects at different levels of sophistication. Project Budburst is suitable for anyone, regardless of experience, and is especially suitable for schools. Project Budburst provides activity guides for native trees and shrubs, native flowers and ornamentals. A set of 18 widely-distributed native species, known as calibration plant species, has been selected to create an extended network of observations with sufficient overlap among observations to allow species responses across the entire country to be compared.

Anybody who is concerned about the impacts of climate change/global warming on our environment should join this effort.  For the investment of a few hours a year, you could help create a very important database that will help scientists study the impacts of global warming on the natural world. Sign up for Project Budburst today!

Picture: Red maple flowers. Picture by Tom Kimmerer

USA National Phenology Network | The Pulse of Our Planet

Is climate change bringing an earlier spring?  Article in SFGate.com