Gardiner Lab

Graduate student Katie Todd and undergraduate Mike Friedman recently presented their research as part of an Ohio Ecological Food and Farm Association Field tour. The field day was held at the Cleveland Botanical Gardens Midtown Learning Farm. Midtown is one of first of now several CBG urban farms that employs Cleveland youth in a summer work-study program. Katie and Mike put together an educational display including bee nests, pinned specimens, and a handout explaining their research, which focuses on the value of urban greenspaces as a nesting habitat.

Graduate student Denisha Parker is going to determine if native lady beetles that have remained common following the introduction of exotic species have a low degree of dietary niche overlap with their competitors. If this is true, it would aid in our understanding of why some species have declined dramatically following exotic introductions while others have remained. Denisha was recently awarded a highly competitive North Central Region Sustainable Agriculture Research and Education Graduate Student Grant ($11,924) to support her work. She will be collecting two species of lady beetles (checker-spot lady beetle (exotic) and orange spotted lady beetle (native)) from our control and high-diversity wildflower vacant lot plots as well as urban farms using sweep nets and sticky traps. Using molecular gut content analysis she will determine the diet of these species and determine how much overlap exists and if it varies by foraging habitat.

Project Description: Native lady beetles are an important group of urban agricultural predators, but in recent decades many have declined dramatically coinciding with introductions of exotic lady beetle competitors. We will determine if the degree of overlap in predator diet, a form of exploitative competition, explains why some native species have declined while others have remained common following exotic establishment.  Using this information, we can manage greenspaces to both conserve native biodiversity and promote urban farm sustainability.

Rachel McLaughlin is an undergraduate researcher in the Gardiner Lab, mentored by Frances Sivakoff. With an undergraduate grant and support from our recent USDA AFRI, Rachel and Frances are studying how soil contamination with cadmium influences the number and length of pollinator visits to sunflowers. Cadmium is found in elevated concentrations in many urban soils with an industrial past, including Cleveland, OH where much of our research takes place. This experiment was conducted on the OSU campus adjacent to a demonstration urban farm, and follows up on research recently published by Sivakoff and Gardiner (Urban Ecosystems, in press), which documented that lead contamination of soils reduced the visit duration of bees to sunflowers.

Over the past year, graduate students Rodney Richardson and Katie Todd have co-authored, and were awarded, two student grants to conduct pollen research in Cleveland, OH. Rodney and Katie are supported by a North Central Region SARE graduate student grant ($11,930) and an OARDC SEEDS graduate student grant ($9,775) to investigate solitary bee’s pollen usage on urban farms. They are mid-way through their first year of pollen collection and will use pollen metabarcoding DNA analysis this fall to determine what their bee larvae were eating in Cleveland this summer. Check out the photos below to see some of their sites and bee X-rays!

Project Summary: Urban agriculture is highly reliant on the pollination services that wild bees provide. In order to support pollinator’s survival and reproduction, we need to supply both crop and non-crop pollen resources for these bees. However, we don’t have a clear picture of what solitary bees feed their young in urban farm environments. Therefore, we don’t know what flower plantings will best support local bees. In order to test what bees eat in urban farms of Cleveland, OH, we will collect bee larvae and pollen with “Bee Hotel” trap nests. We will then conduct a DNA analysis on the pollen within these nests in order to determine what floral resources are critical for solitary bee reproduction. With this insight into urban bee foraging behavior and reproductive success, our study will inform farmers about urban habitat management to support future generations of urban bees and urban farm sustainability.

Graduate Student Denisha Parker, undergraduate Ryan Byler, and Mary Gardiner participated in a fun outreach event on Sunday showcasing the Central Neighborhood of Cleveland, OH. Community College Avenue was closed to traffic from 1-5 pm on Sunday 7/16/17 allowing families to walk among five activity hubs. One of our prairie sites fell within the arts and culture hub. We had the opportunity to meet our neighbors, talk with community members about our study, and most importantly collect some bugs with a great group of children. Below are some photos of Denisha and Ryan helping the budding entomologists to wrangle their catch!

Chris Riley, Dan Herms, and Mary Gardiner recently published a paper as part of a special issue of Urban Forestry and Urban Greening titled: Exotic trees contribute to urban forest diversity and ecosystem services in inner-city Cleveland, OH.

This study highlights the importance of vacant land to the urban forest – these sites had three times as many trees as residential sites! The majority of trees found on vacant land are exotic and naturally regenerated. This weedy forest, such as the tree-of-heaven individuals which have sprouted up alongside the abandoned building in the photo below are not traditionally thought to provide any benefits in their invaded ecosystems. But, in inner-city Cleveland exotic trees are providing many ecosystem services such as energy cost reduction, pollution removal and increased storm water infiltration. How the presence of these species influences the biodiversity of tree-dwelling herbivores and their predators in vacant lots is currently being investigated by Chris Riley.

Our paper was recently featured in the Anthropocene Weekly Science Magazine and is also highlighted on the OSU Grant development Support Unit Website.

Its amazing how quickly the vegetation shifts in an urban prairie. This week bee balm (Monarda fistulosa) is in full bloom! This native Ohio wildflower took three years to bloom in our plots, it is highly attractive to pollinators. Photos of the pocket prairies from June and July are archived HERE.

Recently, PhD student Yvan Delgado de la Flor was funded by an OARDC SEEDS graduate student grant to inventory the spider fauna within a region of Peru. Yvan has made one trip to initiate the study and train a great group of undergraduates who are helping him to collect spiders from several habitats within the Cusco region of the tropical Andes. A  project summary and some photos from his first research trip are below.

Project Summary: Biodiversity assessments are critical for setting conservation goals as they can reveal changes in species composition providing evidence about the impact of human activity on natural habitats and wildlife communities. The tropical Andes is one of the most important biological hotspots on Earth, yet its fauna and flora remain mostly unknown to science. In 1911, Yale University organized an expedition to assess the biodiversity of Cusco, a region located in the tropical Andes of Peru. This resulted in the description of several new species, and the discovery of Machu Picchu. In collaboration with Peruvian institutions, we aim to replicate the Yale expedition. To do this, we will assess the current diversity and distribution of spiders in Cusco, and determine whether spider communities have changed following 100 years of human mediated habitat change in the region.

The USDA National Institute for Food and Agriculture has announced their grant awardees for the Pests and Beneficial Species program and Frances Sivakoff and Mary Gardiner  along with our collaborators Reed Johnson (OSU) and Amy Toth (ISU) are one of the 21 funded projects! See the full list of awardees at: https://nifa.usda.gov/announcement/usda-invests-76-million-research-pests-and-beneficial-species. Details about our new project below.

LANDSCAPE LEGACY AND URBAN AGRICULTURE: UNDERSTANDING THE IMPACT OF HEAVY METAL CONTAMINATION ON POLLINATOR HEALTH AND POLLINATION SERVICES

Project Summary: Cleveland OH’s formerly densely-populated inner-city neighborhoods now contain over 27,000 vacant lots as a result of protracted economic decline and the recent home foreclosure crisis. Currently, there are over 250 urban agroecosystems established on formerly vacant land across Cleveland. The sustainability of urban agriculture requires reliable ecosystem services, including pollination. A landscape legacy of heavy metal (HM) soil contamination represents a key threat to pollinators. We propose to study the impact of HM contamination on bee foraging behavior, bumblebee colony health, and pollination. Our work will begin by examining how soil HM contamination influences bee visitation and pollination services of focal crop plants (Objective 1). Next, we will focus on how foraging on contaminated provisions influences colony health, including reproductive potential, nutritional state, immunity, and detoxification (Objective 2). Third, we will track individual pollinators throughout an urban agroecosystem to determine how HM exposure influences their overall foraging patterns and efficiency (Objective 3). Finally, we will determine the weedy flora that provide key resources for pollinators and identify how these plants vary in their concentration of HM (Objective 4). In accomplishing our objectives, we will elucidate the effects of HMs on a vital ecosystem service necessary to attain sustainability and security in urban agriculture.

Coneflower is starting to bloom in the Cleveland Pocket Prairies!