Budding Darwins and other amateur naturalists can help a nationwide project as they watch the autumn aspens turn gold.

The timing of aspen leaf changes and other natural events such as pollination, bird nesting and animal mating are all important to scientists studying climate change. Ordinary citizens can help scientists track the events by recording observations of aspens and 299 other plant and animal species through the USA National Phenology Network.

"Phenology is the study of the seasonal life-cycle events in plants and animals — things like when leaves come out or change color, when flowers open, when birds migrate, when insects molt," said Theresa M. Crimmins, outreach coordinator for the National Phenology Network, via email. "Our organization has been established to track these events across the nation because phenology has been identified as a key indicator of climate change. For example, many events are occurring earlier in the spring with warmer spring temperatures."

The project has an online interactive map and visualization tool where information is posted for various locations around the country. Only half a dozen New Mexicans are participating in the network, tracking changes of juniper, ponderosa pine, aspen and cheatgrass in the state. Data, maps and models from observers are open for use by anyone.

"We encourage tracking of events throughout the year — for example, when leaves turn color and fall from trees in addition to when they begin to green up and grow," Crimmins said.

Scientists use phenological data to study changes in ecosystems, such as how climate shifts impact forests through insects, disease and fire.

The network was founded in 2005 by the U.S. Geological Survey, the University of Arizona, the University of Wisconsin-Milwaukee, the National Science Foundation, the U.S. Fish and Wildlife Service and the U.S. Environmental Protection Agency. Today, they partner with two dozen other universities, conservation groups and government agencies to promote and operate the network.

The online monitoring system wasn't launched until 2009. When the new website went live that March, the site crashed from so many people clicking on it to take a look. Several thousand people joined the network and reported hundreds of thousands of observations in the first year.

Nature's Notebook, a link on the Phenology Network website, lets people choose a state and view a list of all the species scientists are tracking as part of the project. More than two dozen are listed for New Mexico. Viewers can click on a plant or animal species to learn more about them and why observing them is important. Then the site tells the observer what to look for and write down to put into the online database.

The quaking aspen, for example, is the "the most widely distributed tree in North America."

An aspen grove, as it turns out, is usually a bunch of trees all connected by the same root system. While aspen trees can grow from seeds, most new tree suckers sprout out of the main root branch growing from a mature parent tree. These ramets (individual members of the colony) are all part and parcel of the same root system, and biologists consider them a single organism or "clone." One aspen clone can cover up to 100 acres and produce thousands of trees.

Scientists also think the aspen clone is one of the longest living organisms. Commonly, a clone can live 5,000 to 10,000 years. Even if the trees die in a wildfire or are cut down, the root system below ground can survive and produce new offspring. The oldest known clone is the Pando in Utah's Fishlake National Forest. Scientists believe the Pando is 80,000 years old.

Why watch aspens change color, besides to appreciate their beauty? The tree is a "calibration plant species" for the National Phenology Network. Changes in the habits and timing of events for these species give scientists an idea of the "big picture" of impacts on plants from climate change.

Some people are allergic to aspens. Tracking the pollen production of these and other sneeze-producing plants in New Mexico, such as junipers and ragweed, can help build a system to warn allergy sufferers.

Contact Staci Matlock at 986-3055 or smatlock@sfnewmexican.com.

ON THE WEB

For more information about the USA National Phenology Network and how to get involved, visit www.usanpn.org/.