Doug Tallamy

Professor, Agriculture and Natural Resources University of Delaware

  • Newark DE

Prof. Tallamy researches how plants that evolved elsewhere impact food webs and biodiversity.

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2 min

In new book, entomologist shows homeowners how to make changes in their yards

They asked, he answered. In his new book, "How Can I Help?: Saving Nature with Your Yard," nationally known University of Delaware entomologist Doug Tallamy addresses the most common questions he receives from homeowners looking to do their part to impact the food web, boost biodiversity and replace invasive plants with native ones. “Change is afoot!” Tallamy writes in the book, which was released today, April 8. “The cultural change from an adversarial relationship with nature to a collaborative one is starting to happen, and it gives me hope about the future of diversity and thus our own future.” Tallamy, TA Baker Professor of Agriculture and Natural Resources, wrote “How Can I Help” to tackle questions he’s received over email and during talks he has given around the U.S. “I get the same questions over and over again,” Tallamy said. “They fall into easily arranged categories: Questions about oaks, questions about ecology, questions about invasive plants. The book almost wrote itself in that sense.” Some of those common questions include: Why should I care about the food web? How should I choose the right native plants for my property? What is the greatest threat to oaks? How do we prioritize which invasive species to get rid of? Are bug zappers hurting insect populations? Is it better to have fewer plants of lots of species or more plants of fewer species? Is it good to feed the birds? Tallamy is available for interviews to discuss "How Can I Help" or other relevant topics. To reach him directly, visit his profile and click on the "connect" button.

Doug Tallamy

6 min

Saving the world, one yard at a time

University of Delaware professor Doug Tallamy has a simple mission: Encourage people to rid their property of invasive plants and replace them with native ones. One of the ways he's tackling it is through a concept called “Homegrown National Park,” a grassroots initiative he co-founded to offer a simple solution for the biodiversity crisis — the decline of a variety of animals, plants and numerous species. Tallamy, the TA Baker Professor of Agriculture and Natural Resources at the University of Delaware, is trying to encourage everyone to do their part to protect the planet. If invasive plants (which don’t belong in an area and can ultimately harm the ecosystem by taking away essential resources from other plants) grow out of control, then an area loses its biodiversity, the ability for multiple plant and animal species to function at once and create a rich ecosystem. Invasive species are prolific. For example, many invasive plants produce berries, which some birds eat. The birds then spread those seeds around. So, once invasive plants are in an area, they’re hard to get rid of. The idea is to replace them with native plants, which have historically belonged to a region and provide critical habitat for insects, birds and other creatures. It's an uphill climb, but Tallamy persists and is trying to save the world, one yard at a time. “Everybody has a responsibility of doing things that sustain their little piece of the earth, and there are a whole bunch of things one individual can do to help in that regard,” Tallamy said. What’s not so simple, however, is getting the Earth’s 8 billion people (or, at least, anyone with property) to do this. “We are trying to change the culture so that [replacing invasive plants with native ones] becomes the norm, not the exception,” Tallamy said. “We’re not getting rid of lawns. But we don’t need 44 million acres of them. There are now so many people on the planet that natural systems are not functioning the way they need to sustain us.” A snowball effect Much of our current plant culture revolves around colorful, aesthetically pleasing ornamental plants that don’t support the local food web. When they grow out of control, a local yard or larger region loses out on biodiversity. The natural world is all connected. For example, Tallamy said, if we lose pollinators like our native bees that transport pollen between plants, then we also lose most of our plants that produce flowers and fruits. It’s a snowball effect. “If that happens, the energy flow through our terrestrial ecosystems is almost totally disrupted, which means the food webs that support our vertebrate animals, our amphibians, our reptiles, our birds and our mammals would collapse and all those animals would disappear,” Tallamy said. “Without insect decomposers, the creatures that break down dead material, mostly plants, would rot and only bacteria and fungi would endure.” “Homegrown National Park” has generated a lot of buzz for Tallamy, who received recognition for it in October by the Massachusetts Horticultural Society. The MHS awarded Tallamy with its highest honor, the George Robert White Medal of Honor, for eminent service in the field of horticulture. Conservation in action Tallamy’s quest to “change the culture” on planting can be witnessed in the fall at UD. On a warm October afternoon, he and a group of students from the Introduction to Insect and Wildlife Field Studies (ENWC 165) course trudged out to UD Wetlands to curtail some pesky invasive plants native to Asia. Equipped with clippers, loppers and handsaws, they walked behind Worrilow Hall, part of the College of Agriculture and Natural Resources’ 350-acre campus, which includes the UD Wetlands, an area that was formerly a dairy cow pasture but transformed into wetlands in 2008 because pollution from the farm was reaching the local watershed. The wetlands were created because wetlands, by design, absorb nitrogen from runoff before it goes into waterways. They then release it as a gas into the atmosphere. But the UD Wetlands repeatedly deal with pesky invasive plants such as Porcelain-berry and Chinese elm. Over the years, UD students have stymied the species from overtaking the area. “See this? This is a good guy,” said Tallamy to the students as he held up a fallen branch. “You just want to get the Porcelain-berry off of it. They’ll grow back very well. But we want to nip [the Porcelain-berry] in the bud.” Taylor Kelly, a senior wildlife ecology and conservation major who took part in the invasive species removal, said Tallamy has helped her better understand the interconnectedness of various ecosystems. “Native plants provide so much value to our local pollinators, which add value to our local birds because they feed on pollinators, seeds, fruit and trees,” Kelly said. When native plants are in their natural environment, she added, it is a beautiful thing to see. Gardening with intention Tallamy, who began his teaching career at the University of Delaware in 1982, has published numerous research papers about entomology and written three books about native plants, insects and ecosystems, with a fourth book soon to come out. Lately, much of his career has revolved around public outreach. He often lectures across the country about native plants and their ecosystem value and is regularly quoted in outlets like The New York Times, The Washington Post and Natural History Magazine. “Dr. Tallamy is a rare scientist that is able to explain his work to everyone,” said Jake Bowman, UD professor of wildlife ecology and chair of the Department of Entomology and Wildlife Ecology. “His passion for the importance of native plants has driven a major shift in thinking.” Years ago, when Tallamy first set out to spread his messages about native plants, he anticipated a lot of pushback from horticulture enthusiasts who he thought might be resentful about being told how to choose their plants. Instead, Tallamy found that many actually embraced his ideas, including Delaware’s own Master Gardeners, a group of about 300 volunteer educators trained by UD Cooperative Extension. Among his supporters are Delaware Master Gardeners Karen Kollias, Brent Marsh and Judy Pfister, who each praised Tallamy for the impact he has had on how they garden. Kollias now “gardens with intention”— not for herself or her neighbors, but for the environment. “I was a gardener before,” she said. “Now I consider myself an ecological gardener.” After Marsh received a copy of Tallamy’s 2007 book, Bringing Nature Home, which talks about the link between native plants and native wildlife, Marsh became a Master Gardener and began planting native species in his Georgetown lawn. Today, native plants such as woodland sunflowers and oak trees adorn Marsh’s yard, and he is grateful for the value of native plants that he learned through Tallamy’s book. “Someday, maybe 20 years from now when I’m 100 years old, somebody's going to buy my house and they’re going to say, ‘Who planted all these oak trees?!’” Marsh chuckled. “Doug Tallamy changed my life.” As Tallamy has sought to simplify scientific knowledge with the general public, Pfister has utilized Tallamy’s approach to do the same. “He has a way of just making the whole thing a big circle, tying the need for a plant back to the need for a bird back to the need for a tree,” she said. Tallamy, who has been delighted by the fervor ignited by his native plants teachings, said the future of the Earth and its diverse ecosystems will in large part depend on how people treat their yards. “In the past, we asked our landscapes to do one thing, and that was, be pretty,” Tallamy said. “Now we have to ask them to do two things: be pretty and ecologically functional. That's the horticultural challenge of today.” But it’s one Tallamy believes can be achieved. Sometimes, he wishes he could speak to his 10-year-old self and tell the young boy to dig another pond for the toads to colonize. Restore. Conserve. Focus on keeping nature’s ecosystems intact, he would say. “We have to do both,” Tallamy said. “Yes, we have to conserve what’s out there, but we have to get in the mindset that we can really put a lot of it back.” Tallamy and Homegrown National Park co-founder Michelle Alfandari have created a database for people to type in their zip code and discover which native plants are best for their area.

Doug Tallamy

1 min

Renowned native plant expert receives yet another honor for his work

After years of writing several bestselling books and making countless media appearances, University of Delaware professor Doug Tallamy has become one of the most well-known advocates for filling yards with native plants. The Massachusetts Horticultural Society (MHS) will honor Tallamy's tireless work at its 121st Honorary Medals Dinner on Oct. 30. Tallamy, a professor in UD's Department of Entomology and Wildlife Ecology, will receive the George Robert White Medal of Honor, MHS’ highest honor, “for eminent service in the field of horticulture," and will also deliver the keynote speech. His New York Times bestselling books include “Nature's Best Hope: A New Approach to Conservation That Starts in Your Yard," "The Nature of Oaks: The Rich Ecology of Our Most Essential Native Trees” and "Bringing Nature Home: How You Can Sustain Wildlife with Native Plants." One of Tallamy's crowning achievements was co-founding Homegrown National Park, an initiative to encourage people to plant native plants and remove invasive ones where they live. Tallamy's research demonstrates how native plants help to preserve the food web by serving as a prime food source for plant-eating insects, which serve as the foundation of the food web. He calls for replacing invasive plants with native plants, and says the loss of natural habitats with diverse native plant populations is harming wildlife, specifically songbird populations. Reporters can connect directly with Tallamy by visiting his profile and clicking on the "contact" button.

Doug Tallamy
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Biography

Doug Tallamy is the T. A. Baker Professor of Agriculture in the Department of Entomology and Wildlife Ecology at the University of Delaware, where he has authored 111 research publications and has taught insect-related courses for 42 years. Chief among his research goals is to better understand the many ways insects interact with plants and how such interactions determine the diversity of animal communities. His book Bringing Nature Home was published by Timber Press in 2007, The Living Landscape, co-authored with Rick Darke, was published in 2014; Nature's Best Hope, a New York Times bestseller, was released in February 2020, and his latest book, The Nature of Oaks, was released in March 2021. In 2021 he cofounded Homegrown National Park with Michelle Alfandari (HomegrownNationalPark.org). His awards include recognition from The Garden Writer’s Association, Audubon, The National Wildlife Federation, Western Carolina University, The Garden Club of America, and The American Horticultural Association. Doug lives with his wife, Cindy, on their restored property in Oxford, PA.

Industry Expertise

Research
Education/Learning

Areas of Expertise

Native Plants
Insect Conservation
Ecological Landscaping
Ecosystem Function

Media Appearances

Creating biodiversity one landscape at a time | Gardener State

My Central Jersey  online

2024-01-28

Article quoted Doug Tallamy, entomology and wildlife ecology, who stated that one of the most important things we can do to support biodiversity is to plant native plant species in our landscapes.

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Gardens blooming with endangered plants could prove a boon to conservation

Science.org  online

2023-08-31

Saving critically endangered plants will require unorthodox solutions like these, says Tallamy. “We’re in the midst of the Earth’s sixth great extinction event. We have parks and preserves, but they’re not good enough. So, we have to practice conservation outside of those.”

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To mow or not to mow? Why there's a culture war happening on your lawn

WTXL Tallahassee  online

2023-05-20

"The ecological I.Q. of this country is really low. We don't get that we are living off the life support that healthy ecosystems provide. If we don't support those ecosystems, we don't have that life support," Doug Tallamy said.

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Articles

Lepidoptera Host Records Accurately Predict Tree Use by Foraging Birds

Northeastern Naturalist

2021

The richness, abundance, and biomass of phytophagous arthropods like lepidopteran larvae is highly uneven among sympatric tree taxa. Optimal foraging theory predicts that predation pressure will be greatest on foraging substrates that support the highest abundance and/or diversity of prey, thus offering the greatest reward and maximizing fitness. Predation pressure can also vary with the nutritional or energetic needs of predators across the annual cycle.

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Are declines in insects and insectivorous birds related?

Ornithological Applications

2021

A flurry of recently published studies indicates that both insects and birds have experienced wide-scale population declines in the last several decades. Curiously, whether insect and bird declines are causally linked has received little empirical attention. Here, we hypothesize that insect declines are an important factor contributing to the decline of insectivorous birds. We further suggest that insect populations essential to insectivorous birds decline whenever non-native lumber, ornamental, or invasive plant species replace native plant communities.

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Few keystone plant genera support the majority of Lepidoptera species

Nature Communications

2020

Functional food webs are essential for the successful conservation of ecological communities, and in terrestrial systems, food webs are built on a foundation of coevolved interactions between plants and their consumers. Here, we collate published data on host plant ranges and associated host plant-Lepidoptera interactions from across the contiguous United States and demonstrate that among ecosystems, distributions of plant-herbivore interactions are consistently skewed, with a small percentage of plant genera supporting the majority of Lepidoptera.

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Education

University of Iowa

Post-Doctoral Fellow

Entomology

1981

University of Maryland

PhD

Entomology

1980

Rutgers University

MS

Entomology

1976

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Affiliations

  • Entomological Society of America
  • Ecological Society of America
  • The Association for the Study of Animal Behaviour
  • The International Heteropterists Society