Mysterious mulberries
Final Update, April 2022
Thank you!
A quick summary: This data is pretty confusing so a closer look at the report on the left is strongly recommended. However, this project resulted in the first ever red mulberry report in iNaturalist in Minnesota and 164% increase in observations of white mulberry in iNaturalist during 2021. Hopefully this line will persuade you to read the report for additional context : "With 312 white or hybridized mulberries to only 6 red mulberries verified observations of likely living, non-native white mulberries and hybrids now outnumber native red mulberries about 1:52."
Project overview
The Mysterious Mulberry project hopes to identify the current distribution of native red mulberry, Morus rubra, and non-native white mulberry, Morus alba, by asking volunteers to find, identify and report these trees in iNaturalist. In addition to providing updated population numbers, these data may also inform future scientific research about the perceived decline of red mulberry and the invasiveness of white mulberry.
How you can help
Report both red and white mulberry to iNaturalist. For this project, only report those trees that grow in nature, not cultivated or tended. If you think it's a hybrid report it as white mulberry and add a comment about your concerns/observations.
Learn more
Red mulberry: Where are they?
Red mulberry, Morus rubra, may be the rarest tree in Minnesota. Red mulberry's native range is thought to include southeastern Minnesota, the same part of the state that's getting warmer and wetter and thus more like areas further south and east that have more red mulberries. So where are Minnesota's red mulberries and why aren't they thriving? Help us better understand where this rare tree with edible fruit is today.
Photo by Sally Weeks, Purdue University
Black alder, Alnus glutinosa
White mulberry: A convincing look-alike
White mulberry, Morus alba, is a non-native mulberry originally from India and China. It has been widely planted in the United States and reproduces and spreads into natural landscapes. White mulberry is commonly misidentified as red mulberry making it very hard to accurately understand where either is found today.
In addition, red and white mulberries can cross-pollinate resulting in hybrids, thus further complicating identification. If you think you've found a hybrid please report it as a white mulberry and add a comment about your identification concerns and why you think it could be a hybrid.
Photo by Sally Weeks, Purdue University.
Identification resource
Purdue University has a great red and white mulberry guide you can access here. Check it out and reference it frequently to make sure you're confident about your ID.
Photos by Sally Weeks, Purdue University
Mysterious Mulberry project inspiration and background
In 2017 The Minnesota Conservation Volunteer magazine ran a great article, The Rarest Tree, about red mulberry. For years I've been thinking about ways to enable volunteers to help us better understand what's happening with this native, fruit-bearing tree that should be thriving in Minnesota's changing climate but is disappearing.
I'm delighted the MN Master Naturalist volunteers have agreed to help make this happen! Special thanks to these MN Master Naturalist trainees for making this project better: Laura Baxley, Aaron Folsom, Joe Jackson, Paul Jacobsen, Melissa McCaleb.
Interested in more information about red mulberry? Check out this Committee on the Status of Endangered Wildlife in Canada report.
Photos by Sally Weeks used with permission of Purdue University.