Up in the Air
Trees are deeply rooted, held fast to the Earth by a web of roots as wide as the canopy above them. Scientists studying trees are not so tightly bound to the ground; studying trees and the species that depend on them has them looking up in the air. In July, we feature a scientist whose fascination with bats continues to grow, how tree breeding gives trees a lift in defending themselves against invasive pests and diseases, how wildfire creates its own atmosphere, and a partnership focused on measuring tree canopy.
Investigate the atmosphere with the GLOBE’s (Global Learning and Observations to Benefit the Environment) science-based protocols for environmental education.
Sybill Amelon does not remember a time when she was not fascinated by wildlife. She began honing her skills in observing nature and recording her observations as a young child, a process that sometimes included bringing varying forms of nature indoors, to her mother’s consternation. “As long as I can remember, I’ve done science stuff, even before I went to school,” Amelon said. “It’s just part of me.”
Today, Amelon is a research wildlife biologist with the Northern Research Station’s lab in Columbia, Missouri, where much of her work, her free-time and her home-life centers on bats. The more she has learned about the similarities and differences that span all species of bats, the more fascinating bats have become for her. “The diversity always amazes me,” Amelon said. “They are such an important component of our ecosystems, yet worldwide so many are in steep decline.”
Amelon’s interest in bats began in the 1990s, when she was a district biologist in the Forest Service’s National Forest System. Her job included evaluating whether proposed management actions would impact bats, but data on which to base that evaluation was sparse. Rather than hunt for research, Amelon decided to do research; she earned a doctorate and later became a scientist with the Northern Research Station.
For the past several years, Amelon’s work has focused on white-nose syndrome, a fast-spreading catastrophe for eastern bats that hibernate in caves. Caused by a non-native fungus, Pseudogymnoascus destructans, or Pd., white-nose syndrome has killed millions of bats since sick bats were first discovered in New York. After many years of research on tools to slow the spread of white-nose syndrome, today Amelon’s work focuses on conservation of surviving bats.
This year, Amelon has been trapping bats and outfitting them with ultra-lightweight transmitters as part of research exploring whether chemicals in the environment affect bats. Before releasing them, she also takes hair and fecal samples for analyses, which will help determine if chemicals are accumulating in bats. “In the wake of white-nose syndrome, it is important that we understand all of the factors that affect the health of bats,” Amelon said. “This research will help us see whether chemicals that are commonly used in the environment might have an effect on bats.”
Amelon’s work with bats does not stay at the office. She volunteers in bat rescue, helping relocate bats that find their way into houses and rehabilitating bats injured in accidents or by people trying to get them out of the house. She is providing foster care to several orphaned baby bats as well as permanently injured bats that are now part of an educational program she conducts for schools and local organizations. “Bats are just remarkable animals,” Amelon said. “I learn something new and surprising all of the time.”
Atmospheric Fire Research
In addition to creating flames, heat and smoke, fires create changes in the atmosphere leading to turbulence which in turn effects fire behavior and smoke dispersion. Scientists at the Northern Research Station are working with collaborators to study this turbulence so that they can provide the best available data to firefighters and inform the decisions they make. A recent publication, “Observations of turbulent heat and momentum fluxes during wildland fires in forested environments” describes results of the latest investigation.
Scientists used data gathered from two prescribed fires conducted in the New Jersey Pinelands National Reserve to determine how atmospheric turbulence varied before, during and after the passage of the fire front. Turbulent heat fluxes during wildfires contribute to convective heating and cooling of fuels, which are key factors in fire spread. They also affect the behavior of the smoke plume, including its size, shape and where it travels.
“This work is important as it increases our understanding of the atmospheric dynamics during fire and lays the foundation for the development of new predictive tools to predict how fires and smoke will move and spread,” said Warren Heilman, research meteorologist with the Northern Research Station based in Lansing, Mich., and lead author on the publication. “In turn, this knowledge helps us anticipate the effects of fire on ecosystem health and human health and safety.”
Into the Canopy
Forest research can take you to new heights; just ask Dave Carey, a research technician at the Northern Research Station’s lab in Delaware, Ohio, whose job has taken him 70 feet in the air via a bucket lift to pollinate beech trees. Carey’s journey to the top of a tree was part of work led by Research Biologist Jennifer Koch to breed trees to be resistant to non-native pests and diseases. These diseases and pests can run unchecked in forests that did not evolve with them and, as a result, trees such as beech, ash and elm have little ability to defend themselves.
Beech bark disease is caused by an invasive beech scale insect that feeds on the bark, creating entry points for fungal infection that weakens and can even kill the tree. Naturally occurring trees with resistance to the scale insect are the basis of Koch’s breeding program.
In 2002, Koch partnered with the Michigan Department of Natural Resources to identify beech trees in Ludington State Park that appeared to have some resistance to beech scale and beech bark disease. The process of increasing the trees’ natural resistance began with Carey getting a lift into the tree canopy in a scissor lift bucket courtesy of the Consumers Energy Electric Company. He collected branches from resistant trees for later pollen collection in the greenhouse and also installed densely woven pollination bags over the branches of selected beech mother trees. The bags prevent the female flowers from being pollinated with unwanted pollen from susceptible trees.
When the Ludington State Park resistant beech trees flowered, Carey again used the bucket truck to return to the canopy to remove the pollination bags and paint pollen collected earlier from the resistant trees on the beech tree’s female flowers. He replaced the pollination bags with mesh bags designed to prevent wildlife from eating developing seeds and later collected mature seeds that researchers hoped would produce a large proportion of resistant seedlings. Subsequent tests showed that when both parents are resistant roughly 50% of the seedlings produced were also resistant to the beech scale insect.
While tree breeding accelerates trees’ ability to develop resistance to pests and disease more quickly than unassisted evolution (natural selection), it takes time to develop trees that have sufficient genetic diversity and pest/disease resistance to be useful in forest restoration. In October 2017, Koch and Carey and the entire research partnership celebrated a significant achievement: planting beech trees in Ludington State Park that were the descendants of the trees first identified as being resistant to beech bark disease 15 years earlier.
“Although tree breeding is not an overnight fix to the invasive species we’re dealing with in forests today, it allows us to help our tree populations survive and adapt to insects and diseases that we are not going to be able to eliminate, keeping our forests healthy and resilient in the long run,” Koch said.
Urban Tree Canopy Assessments
Trees growing in urban areas help create the ambiance that makes a downtown special. In addition to their beauty and cooling shade, urban trees provide many ecosystem services including wildlife habitat, reducing air pollution and storm water runoff. Scientists now have the ability to qualify and quantify the benefits of urban trees using the Urban Tree Canopy Assessment suite of tools. Forward-looking community groups are partnering with the USDA Forest Service to gather data about their forests so that they may better plan for the health and long-term sustainability of the benefits trees provide.
One such group is the South Central Regional Council of Governments (SCRCOG) in Connecticut. In the process of updating two regional plans, they were asked to address the issue of trees, including the potential benefits in terms of pollution reduction, stormwater management, alleviation of urban heat, creation of wildlife habitat, and strengthening a sense of place in the communities.
The Council of Governments reached out to Jarlath O’Neil-Dunne of the Spatial Analysis Laboratory at the University of Vermont who is funded in part by the USDA Forest Service Northern Research Station. O’Neil-Dunne is known to have a vast experience in conducting Tree Canopy Assessments including an assessment of New Haven, Connecticut.
The Tree Canopy Assessment was conducted from August 2018 through May 2019 in 15 municipalities in the South Central Region of the state and has provided the Council of Governments with detailed information on existing and potential tree canopy in the region. “Jarlath’s suggestions and ideas throughout the process have improved the assessment and allowed for the development of several valuable databases,” said Eugene Livshits, Senior Regional Planner for the South Central Regional Council of Governments. “He has worked very hard to make the findings most useful to the Region and the 15 municipalities.”
SCRCOG is currently in the process of reviewing the results and analysis of the assessment, which will be presented to the Regional Urban Forestry committee in late summer or early fall of 2019.
Having a latte in the shade at an outdoor café, relaxing under an old oak tree in a city courtyard, and waiting for a bus sheltered from the sun by vegetation are made possible by the presence of an urban tree canopy, the layer of tree leaves, stems and branches that provide tree cover.