BiodiverseCity St. Louis logoBiodiverseCity St. Louis is a growing network of organizations and individuals throughout the greater St. Louis region who share a stake in improving quality of life for all through actions that welcome nature into our urban, suburban and rural communities.

BiodiverseCity St. Louis recognizes our region's reliance on biodiversity, the variety of life, and natural systems. We depend on biodiversity, not only for the air we breathe, the water we drink, and the food we eat, but also for the basic health, livability and economic prosperity of our region.

Species Spotlight

Pawpaw
(Asimina triloba)

Pawpaw fruit
© Matilda Adams/Missouri Botanical Garden
 

When you think of fruit, what comes to mind? A crisp shiny red apple, a luscious cool watermelon on a scorching summer day, or a succulent orange from the Sunshine State? These fruits are delicious, extremely popular, and cultivated throughout the Americas today. Though beloved, these highly renowned fruits are species introduced to the Americas by humans centuries ago. There has been one delectable fruit here all along; paleontological evidence suggests they have been present for tens of millions of years. The largest edible fruit in North America, waiting, growing, ripening on a tree in a nearby woodland. Have you guessed it yet? The pawpaw fruit of the common pawpaw tree, Asimina triloba!

The pawpaw is a woodland, understory, deciduous tree species, reaching a height of 15 to 30 feet. It has large leaves that mature to a golden yellow in the fall and produces a yellowish green to brown fruit.

Pawpaw flower
© Nathan Kwarta/Missouri Botanical Garden
 

The native range of the pawpaw tree stretches across the eastern, southern, and midwestern United States from New York to Nebraska, south to Florida and eastern Texas. Pawpaw trees thrive in shade, prefer moist, well-drained soils and are often found growing in colonies near creeks or floodplains. Pawpaw trees are unique in that they are pollinated by flies and beetles. In spring, the inconspicuous maroon flowers effuse a rancid odor, smelling like rotting meat. The blooms do not offer a sweet scent or a nectar reward for pollinators like bees and butterflies. However, the pawpaw is the only host plant for zebra swallowtail butterflies whose caterpillars munch on the leaves.

It’s no surprise if you have never heard of the pawpaw, as you will not find this sweet and aromatic fruit at your favorite chain grocery store. If you regularly adventure to your local farmers market, you might be lucky enough to encounter this racoon-and opossum-coveted fruit in late August through mid-September. The pawpaw fruit has a short shelf life, does not ripen well after harvesting, and bruises very easily. These factors make the pawpaw fruit difficult to commodify.

Have no fret or fear, if you too crave the sweet banana-mango flavor paired with a creamy-custard like texture of a pawpaw fruit, you can grow your own pawpaw trees. The pawpaw tree is deer-resistant due to a trait hidden in its genetics. When crushed, the leaves of the pawpaw tree emit a strong unpleasant odor and taste. This natural defense ensures that pawpaw trees are mostly pest-free.

One important thing to remember if you want to grow pawpaw trees is that they are self-incompatible. That means that they require cross pollination between two different genetically distinct trees to produce fruit. Additionally, the flowers are protogynous, meaning that they go through a female stage first before maturing into a male stage. To ensure a bigger yield of fruit, hand pollination can be beneficial. Pollen is transferred from a mature maroon flower to a young green, glossy stigma of another tree’s flower. It can take five to eight years, or even ten years, before a pawpaw tree sets fruit when grown from seed. If you want fruit sooner, a grafted tree will typically set fruit in three to four years.

Plant some pawpaw trees this spring in your garden. In the meantime, visit local farmer’s markets, and come end of summer, I hope you can enjoy the sweet taste of North America’s largest edible native fruit.

Learn more about the pawpaw tree on Missouri Botanical Garden’s Plant Finder website.

—Joshua Moore
Community Landscape Specialist, Missouri Botanical Garden

 

 

 

Nutrient Loss Reduction

 

Polluted streamNutrient pollution causing gulf hypoxia has become one of the nation’s costliest and most challenging environmental problems. Over the past 50 years, the amount of nitrogen and phosphorus pollutants entering our nation’s waters has increased, negatively impacting human health, aquatic ecosystems, and the economy.

You can help by: 

  • Minimizing the use of fertilizers and avoid applying fertilizer or pesticides before it rains
  • Planting native species to soak up runoff
  • Installing rain barrels to capture runoff and use it for watering
  • Keeping chemicals like paint, motor oil, and household cleaners out of drains or the ground
  • Supporting infrastructure improvements to maintain and upgrade septic and sewer systems

Missouri Botanical Garden is partnering with Ducks Unlimited, Missouri Department of Natural Resources, and MidAmerica Clean Future Alliance to increase awareness about the Gulf hypoxic zone.

Learn more on Ducks Unlimited’s webpage about Nutrient Loss Reduction Strategies.

 

 

Honeysuckle Sweep Month

 

Volunteers posing with honeysuckle they had removed Volunteer at an event near you!
To energize the greater St. Louis region around improving habitat for our native plants and animals, area conservation organizations will join this March for Honeysuckle Sweep Month. We spotlight invasive bush honeysuckle and the need to remove it so that large swaths of land can become productive areas for native habitat, recreation, and enjoyment.

Learn more and sign up for a honeysuckle hack.

 

 

 

2026 City Nature Challenge

 

City Nature Challenge graphicThe City Nature Challenge, a global bioblitz competition, is April 24–27, 2026.

Make observations of the natural world on iNaturalist between April 24–27th in the St. Louis Region and contribute to a worldwide effort of data collection. Stay tuned for more information about this year’s Challenge and local events!

 

 

Great Listen

 

The Power of One Health Part 1: Understanding One Health
Nature Boost Podcast Episode
Hosted by Missouri Department of Conservation

Nature Boost logoOur health is impacted by the natural world—whether it be the trees that produce the air we breathe, the fruits and vegetables grown from the soil, or the water we drink from the faucet. All of this weaves together into one giant living system; this is what scientists and environmentalists call “One Health,” a way of thinking that recognizes how the wellbeing of people, animals, and the environment are all connected.

Nature Boost, the podcast that “explores the outdoors in Missouri, one adventure at a time,” hosted by Jill Pritchard from the Missouri Department of Conservation (MDC), recently featured experts on One Health to educate listeners about this vital connectivity. Host Jill Pritchard sat down with MDC Policy Supervisor Lorisa Smith and MDC Science Branch Chief and State Wildlife Veterinarian, Dr. Sherri Russell, to discuss nature’s role as "lifestyle medicine." The data is clear: time spent outdoors is medicinal, offering significant physical and mental health benefits that act as an antidote to our digital lives.

The 30-minute conversation emphasizes that biodiversity isn’t just a conservation goal; it’s a foundation for human health. Time in nature can serve as a powerful balancer for the "blue light" and digital transformation of modern society. Beyond just feeling good, nature acts as a preventative therapy, lowering cortisol levels and blood pressure while building mental resilience. By viewing nature as a foundational part of healthcare, the episode suggests that a "nature diet" is just as vital as physical exercise or nutrition for preventing chronic disease and improving cognitive function.

However, in a digital age, we can use technology as a tool to connect us to nature instead of viewing it as an "either-or" choice. Dr. Russell suggests using an app called “Nature Quant” that provides a "nature score." Much like a diet or exercise tracking app, it holds us accountable for our time spent outdoors. In our busy lives, it can be hard to find time to step away. On average, Americans now spend 97% of their time indoors. Research suggests that shifting even a small fraction of that time outside to reach at least 120 minutes per week (about 17 minutes a day) is the minimum threshold needed to maintain good health.

If you are someone who spends a lot of time at a desk or indoors, I challenge you to spend 17 minutes a day outdoors this spring as the weather gets warmer and the days get longer. I imagine the more time you spend outside, the more you’ll learn to care for the environment and notice the positive impact on your mood and health. The message is simple: nature takes care of us when we take care of nature. When we invest in clean water and healthy wildlife, we are ultimately investing in our own communities and our own bodies.

Listen to the full episode and learn more about One Health.

—Review written by Hannah Gibson
Community Conservation Coordinator, Missouri Botanical Garden

 
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