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So far Annemarie has created 25 entries.

Would you give a few minutes a year to reveal the future of forests?

What would be the easiest citizen science project ever? Watching paint dry? Falling off a log? Maybe. But what would you, or anyone else, learn from that?

We are starting a citizen science project almost as easy but much more important. Its called A Tree’s Life and all you need to do is monitor red maple growth in your yard. We even give you the supplies. It’s really just one supply called a dendrometer, and it does most of the work.

We want to measure trees because they have a very important job to do. Trees take carbon dioxide (a greenhouse gas) from the air and release oxygen. Even more important, though, is that they use the carbon to build more tree tissue. That’s how they grow, and as they grow, they store carbon that would otherwise remain in the atmosphere.

Dendrometers are flexible plastic rulers that are installed on the tree’s trunk and expand as the tree grows. Photos: Michael Just

Trees provide many other services like filtering air and water, providing shade to reduce energy costs, and generally make life better. Unfortunately, warming from urbanization and from climate change can reduce tree growth due to water stress, pests, and other factors. In other cases warming might make trees grow more and become healthier due to a longer growing season.

The problem we want to address is that no one knows how trees in different habitats (urban, suburban, rural) and different latitudes will respond. So how can one predict the rate of carbon accumulation in the atmosphere, and thus climate change, if we don’t know how the primary terrestrial carbon sinks – trees – will respond? We can’t. Can we predict where urban trees and forests will thrive or decline? Not very well.

Our goal is to monitor the growth, and thus carbon sequestration, of hundreds or thousands of trees to help figure this out. If you have a red maple and a few minutes each year, please help us. You will contribute to our (all of humanity’s) understanding of how climate change and urbanization will affect forest health and carbon sequestration by trees.

Find out more about the study and sign up to participate.

March 7th, 2017|Categories: Feature, Urban Ecology|Tags: , , |

New Paper – Cities: more of the same for people and animals

Say you are on a road trip. You fall asleep, head lodged against the (hopefully passenger side) window. The last thing you see before drifting off is a string of stores: Starbucks, Target, Bed Bath and Beyond, Walmart, Home Depot……Zzzzzzzzz.

You wake up in half an hour, 2 hours, or 3 days, peek your eyes open and think you haven’t moved at all. The same string of stores would be outside your window again and again. Stop to eat in downtown Atlanta, San Antonio, Seattle or any city in between and you have the same experience. A few unique restaurants you never heard of and maybe you can track down some regional specialty but for the most part you have the same foods as in your home city.

Look familiar? GoogleMaps.

This is called ‘urban homogenization’ and animals experience the same problem. Herbivorous insects and pollinators find the same plant species in urban landscapes across the country. Look outside your window. Do you see holly, boxwood, azalea, ligustrum, and cherry laurel shrubs? How about the trees?: red maple, lacebark elm, crape myrtle, crab apple? Since the plant community looks similar so does the community of arthropods that use those plants for food. Bugs that need a ‘regional specialty’ may be excluded from urban ecosystems.

The temperature, soil moisture, and air quality of distant cities are often more similar to each other than each city is to local natural areas. Kevin McCluney, a former postdoc in our lab (now at Bowling Green State University), conducted a study to determine if environmental homogenization among cities led to homogenization in arthropod hydration (or dehydration).

Can you guess which is Orlando, Raleigh, and Phoenix? Photos: Kevin McCluney.

Now, check out how different the natural environments are surrounding these three cities. They are in the same order as above: Raleigh, Phoenix, and Orlando. In the third photo, Kevin McCluney takes measurements outside of Orlando.

In a new paper, Kevin and coauthors report that due to homogenization in plant communities and landscape maintenance practices, like irrigation, that arthropods in a wet city (Orlando) and temperate city (Raleigh) were less hydrated than in adjacent natural areas but arthropods from a dry city (Phoenix) were more hydrated than arthropods from the adjacent desert areas. Thus, arthropods in very different background climates become more physiologically similar in cities.

Arthropod hydration and other physiological traits like heat tolerance affect their survival, plant and prey consumption, activity patterns, and reproduction. Understanding how physiological states change in cities can help predict the fate of species we are trying to conserve and the damage caused by pests to improve urban plant and wildlife management.

Read the full article:

McCluney,K.E., Burdine, J.D., Frank, S.D. (2017) Variation in arthropod hydration across US cities with distinct climate. Journal of Urban Ecology, 3 (1): jux003. doi: 10.1093/jue/jux003

March 3rd, 2017|Categories: Urban Ecology|Tags: , |

As spiders leave the kitchen, pests keep cooking

A spider in the family Anyphaenidae has made its home on a twig infested with scale insects.  Photo: Emily Meineke, Harvard University

I think by now most people accept that we can’t hope to preserve all extant creatures over the next 50 or 100 years. Global changes in temperature and habitat will help some species and hurt others, as Elsa Youngsteadt showed in her recent paper. Since we can’t save every creature, what is really important to protect? Increasingly, people try to understand and protect species and ecological interactions that generate ecosystem services for people, rather than diversity per se.

Former undergraduate researcher Anna Holmquist examines branches in the field. Photo: Emily Meineke, Harvard University

Urban warming makes street tree temperatures similar to what is expected under climate change, so we have studied them to predict the effects of warming – urban and global – on pest abundance and tree health. Street trees also host a surprising amount of arthropod diversity if you just look hard enough. In a new paper, our former graduate and undergraduate students, Emily Meineke and Anna Holmquist, with help from Gina Wimp at GWU, studied the effects of warming on spider communities in street tree canopies.

The team tested two predictions. Spiders like to eat and often become more abundant in places where prey is more abundant. So we predicted that, since heat increases herbivore abundance, spider abundance would follow. However, because some spiders probably benefit from warming while others do not, we predicted the composition (member species) of the spider community would be different in hot and cool trees.

The fitness of this spider probably increases with warming since it is hot and sweaty from exercise and yoga. Other spiders (not pictured, you can only work kids so hard) die in, or leave, hot places. Thus, yoga spiders will be more common on hot trees and the community composition will change. Artwork by: I.F.

Ghost spiders, like this one, are nondescript but perform important ecosystem functions. Photo: Matt Bertone, NCSU.

Spiders were by far the most abundant natural enemy group. However, as herbivore abundance increased with warming, spider abundance stayed the same. This is bad news for trees because it means that herbivores can increase unchecked. Instead, urban warming altered spider community structure due in part to a whole family of spiders, Anyphaenids — aptly named ghost spiders – virtually disappearing from the hottest trees in one year of the study. This is bad news for conserving urban biodiversity and also because ghost spiders feed on particular pests like lace bugs.

In this experiment, warming reduced biodiversity but also likely reduces biological control by predators, an important ecosystem service. Something happens in these trees to make a common ecological interaction – predators congregating to prey – stop happening. The consequence is that pests go nuts and trees suffer.

Read the full paper here:
Meineke, E.K., Holmquist, A.J., Wimp, G.M., Frank, S.D. (2017) Changes in spider community composition are associated with urban temperature, not herbivore abundance. Journal of Urban Ecology, 3 (1): juw010. doi: 10.1093/jue/juw010.

January 26th, 2017|Categories: Feature, Natural Enemies, Urban Ecology|Tags: , , , |

Who wins and loses with warming? Where you live matters.

Climate change is generally considered bad for people, earth’s biomes, and, of course, polar bears. But as the climate warms will all critters suffer? Will they all be affected the same way? No. In addition to the losers who slowly fizzle out under the oppressive heat, there will be winners who benefit from warming.

An animal’s response to climate change depends largely on two things: the amount of warming in a habitat and the physiological limits of the animal. It has been shown pretty convincingly that animals closer to the equator are more sensitive to warming than animals farther north. I know what you are thinking, “but tropical animals are hot all the time, they should be used to it.” I thought the same thing, but how it works is that since they are hot all the time, they live close to their thermal limits. So for animals in hot places, a little more heat pushes them over the edge.

Therefore the biological effects of climate change are expected to vary geographically, particularly for ectothermic animals such as insects. Elsa Youngsteadt and other folks in the lab took a road trip to test the hypothesis that insects at high latitudes, where it is cold, should generally benefit from warming whereas insects at low latitudes should have mixed responses: some should benefit, but others should be pushed over their thermal limits.

In a brilliant new paper Elsa reports her findings from this trip. The team sampled insects from street trees in the hottest and coolest parts of four cities–Raleigh, Baltimore, Queens, and Boston–taking advantage of the urban heat island effect as a natural warming experiment.

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Four cities at different latitudes were chosen to study warming effects on insect communities. Background map from the National Biomass and Carbon Dataset.

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One of the authors, Andrew Ernst, takes measurements at a typical study tree. Photo: E.K. Youngsteadt


In the lowest latitude city, Raleigh, some taxa became more abundant with warming while others declined. This suggests that, although some species benefited from warming, just as many species suffered. In the coldest and highest latitude city, Boston, most insect groups were unaffected or became more abundant, suggesting that warming was good for most species living in a frigid northern metropolis. Just as predicted! This doesn’t happen very often.

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Yellow sticky cards were used to sample insect communities in urban trees. Photo: E.K. Youngsteadt.

It seems good that not all taxa tank in Raleigh–but the fact that some benefit and others decline could be ecologically disruptive, too: Maybe a parasitoid and its host respond differently, or a predator and its prey. This sort of mismatch could lead to extinction of higher trophic levels if the prey does poorly, or herbivore outbreaks if the predator fails.

I’ll warn you upfront, this paper is dense and there are probably a lot of new concepts packed in that most people will need time to unpack. However, capturing the response of a whole community to a couple degrees of warming is novel and worth the read. Think about the responses of your favorite organisms. Not just in cities but across the globe.

Read the paper here.

December 16th, 2016|Categories: Urban Ecology|Tags: , , , |

Bees and army bands: The remarkable life of TB Mitchell

This is a guest post from our Research Associate, Elsa Youngsteadt

T. Mitchell

A portrait of T.B. Mitchell in the lab. Image courtesy of Special Collections Research Center, North Carolina State University Libraries; photographer unknown.

T.B. Mitchell is probably the reason we ecologists in eastern North America can identify our bees. Mitchell joined the faculty here at NC State in 1925 and distinguished himself as a meticulous taxonomist.

Although he died in 1983, more than 30,000 of his bee specimens are housed here in the NC State Insect Museum, where one can occasionally feel a little time warp: The specimen I am examining right now, under the microscope, was alive in 1925. It was cruising from flower to flower along some North Carolina country roadside 91 years ago when Mitchell nabbed it with his net. He pinned it, identified it, labeled it, may have studied it while writing the key I’m now using—and I’m handling that exact bee, comparing it to one of the same species that I caught last week.

Enough of this kind of thing, and you wish you could meet the guy who made the collection. Thanks to lab alum April Hamblin’s idea to propose a Heritage column for American Entomologist, we nearly feel that we have. April, Margarita López-Uribe, Heather Moylett, and I spent the better part of a year, off and on, going through boxes of letters and stacks of theses, reading Mitchell’s papers, and conducting interviews and correspondence—including actual paper letters. The resulting article is published in the fall 2016 American Entomologist. We invite you to read it and get acquainted with this energetic, unflappable gentleman, his scientific contributions, and his remarkable experiences as a musician and entomologist.

August 30th, 2016|Categories: Lab Happenings, Natural History and Scientific Adventures, Pollinators|Tags: |

Emerald ash borer cropping up in new NC counties

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Silhouette of an ash tree infested with EAB showing classic thinning in the crown. Photo: David Cappaert, Bugwood.org

Emerald ash borer is continuing to spread through NC. So far this summer, it’s already been found in four new NC counties (Davidson, Forsyth, Swain, and Yancey). At this rate, the NC Forest Service is anticipating a lot more findings and is asking folks to keep their eyes peeled for tell-tale signs of beetle activity.

Check out this month’s Forest Health Note for more info on EAB in NC.

July 21st, 2016|Categories: Urban Ecology|Tags: , , |

Post-doc position available in the Frank Lab

A postdoctoral position is available to work in my lab in the Department of Entomology at North Carolina State University, in collaboration with Rob Dunn in the Department of Applied Ecology, as well as a broader group of scholars studying cities at NCSU.

Funding will be partially or fully to examine how urban heat islands and global climate change affect urban and natural forest health. We are interested in the influence of urban heat islands and, more generally, climate on tree pest physiology, symbionts (of diverse sorts), trophic interactions, and the distribution of tree associated taxa. We also consider how changes in urban tree health and density affect human health.

For more information, check out the full position description, and my lab website to read some of our papers on urban decomposition, urban warming affects on trees, pests, parasitoid phenology, and climate change.

To apply, submit CV, cover letter, and email addresses of three references to Steve Frank (sdfrank@ncsu.edu). Cover letter should include a description of research interests and experience and how they could contribute to the lab and project goals.

Lady beetle approaching an aphid on tulip poplar. Photo: SD Frank

Lady beetle approaching an aphid on tulip poplar. Photo: SD Frank

January 6th, 2016|Categories: Lab Happenings, Urban Ecology|Tags: |

Dates set for 2016 Ornamental Workshop on Diseases and Insects at Kanuga

Everyone’s favorite biennial workshop on insects and diseases of ornamentals is scheduled for October 24-27, 2016 at Kanuga Conference Center in Hendersonville, NC.

Workshop title and discipline-specific schedules are still TBD, but go ahead and bookmark the new workshop website, ecoipm.org/ornamental-workshop/, and stay tuned for updates as the time draws nearer.

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Spoils of a 2014 fungal foray. Photo: Annemarie Nagle

November 23rd, 2015|Categories: Landscape IPM|Tags: , |

Urban environments increase pathogen pressure on honey bees

bee2_elsa1Our lab’s latest paper, co-authored by Elsa Youngsteadt and Holden Appler, was published today in PLOS ONE. We examined pathogen pressure and immune response in managed and feral honey bee workers from hives located in urban* and non-urban environments. We found some very interesting results, and as science usually goes, we now have a lot more questions.

The urban bees we examined in the study, regardless of whether they were feral or managed, had higher levels of the fungal pathogen Nosema ceranae and Black Queen Cell Virus. We also tested the survival of urban bees in the lab and compared it to their more rural neighbors. Survival for bees in the most urban environments was three times lower than for those in the most rural environments.

Given the stress factors that urban settings present to foraging bees (such as pollution and higher temps), it’s easy to imagine that a compromised immune system in the urbanites might be the culprit. Kinda like when you get super stressed and stay up all night cramming for that big exam (or partying) and find yourself with a cold a few days later. But, our data didn’t support this idea; we didn’t observe a stronger immune response in rural bees relative to urban bees. Something else seems to be contributing to the higher pathogen pressures we saw in the urban bees.

We hypothesized that that ‘something else’ could be urban factors working in favor of the pathogens, making them more abundant or easier to transmit between honey bee workers from different hives. Higher frequency of worker visits at scarce urban food sources could increase the likelihood that bees will pick up diseases from their environment (think the public water fountain or the notorious buffet line). The fungal pathogen in question, N. ceranae, has also been shown to benefit from the warmer temps we see in cities.

This study sets the stage for so many more questions. If urban environments indeed enhance pathogen survival and change the way diseases spread through honey bee populations, is this a red flag for native bee species that share floral and other resources in these cramped urban landscapes? Is urbanization harming them too? Could pathogens jump from honey bees to native bees because they are more abundant or doing better in the city environment? April Hamblin and Margarita López-Uribe are looking into some of these questions and trying to tease out the effects urban living has on our neighborhood native bees.

Check out the paper for some more interesting findings not covered here, and stay tuned for more to come in the native bee department.

*the level of “urban-ness” for each hive was determined using the amount of impermeable surface (concrete, pavement, etc.) in the typical radius a worker bee flies from the hive, 1500 m.

November 4th, 2015|Categories: Lab Happenings, Pollinators|Tags: , , |

Article covering our recent conference on pollinators

Megachile_blackeyed_susan_smallWe recently co-organized the first National Conference on Protecting Pollinators in Ornamental Landscapes with extension colleagues from Michigan State, held Oct. 12-14 in beautiful Hendersonville NC.

Check out this recent article in Greenhouse Grower for details.

October 26th, 2015|Categories: Lab Happenings, Pollinators||