Mature green ash bark has many ridges and furrows and often has a yellowish tint. Stems will be smooth and have terminal buds (buds at the end) that look like a Phillip’s head screwdriver.
Plant of the Month: Green ash
chase.bergeson • July 14, 2023
Green ash (Fraxinus pennsylvanica)
Green ash (Fraxinus pennsylvanica) is the plant that we have recorded the most times at our wetland monitoring sites. We see many of its saplings at our site as well as mature trees. So how could it be in danger?
Green ash is on the International Union for Conservation of Nature’s (IUCN) Red List as critically endangered due to its vulnerability to an invasive Asian beetle: the emerald ash borer. In NC, white ash, pumpkin ash, and Carolina ash are also vulnerable. This beetle lays its eggs on ash trees and larval emerald ash borers will feed on the tree, killing it, before flying to infest new trees. They have been responsible for the deaths of millions of trees and are likely to continue spreading. Human transportation of ash lumber, including firewood, has accelerated the spread of the emerald ash borer. There are some strategies for protecting trees, including cutting and burning infected trees to stop the spread and introducing predatory wasps. There is also promising evidence that some ash trees may show resistance to the beetle. However, it is likely that ash tree populations will continue to decline. You can find the extent of the emerald ash borer in North Carolina here. For more information: http://www.ncforestservice.gov/forest_health/fh_eabfaq.htm
Green ash is a Facultative Wetland (FACW) plant in the Piedmont and the Coastal Plain, meaning you are more likely to find it in a wetland than in an upland. It makes sense why we see so many at our wetland sites.
In summertime, a great way to identify many trees is by their leaves. What do you think of when you picture a leaf? How many leaves do you see pictured below?
One big leaf! Many Leaflets
Photo By: Alexander Rumpel
One leaf- 3 leaflets
Photo By: Lucie Baret
One leaf!
Photo By: beepboop
Each picture is of one leaf! The leaf is the part of the plant that connects to the stem at a leaf bud. Ash trees have compound leaves, which means that their leaves have multiple leaflets- which do not connect at leaf buds but are part of the leaf as a whole. Young green ash saplings may not have compound leaves.
Green ash leaflets are oval or lance shaped and toothed. They have a light green underside.

Just like red maples (Acer Rubrum), ash trees are one of the few trees that have opposite branching, meaning that one branch should always have a twin growing at 180 degrees from it. Of course, in the life of the tree one of the branches might fall off or be damaged, so always check for any opposite branching on the tree. If you can look closely, you might see a scar on the tree where you would expect to see a branch, indicating that there used to be one present.
Leaf
Photo By: Miles Panych
Leaf underside
Photo By: Miles Panych
Opposite branching and leaf buds
Photo By: James Mickley
Green ash trees may be confused for Carolina ash trees, but are often difficult to distinguish without the presence of its fruits (samaras). Green ash samaras are thin and pointy, while Carolina ash samaras are rounder. Although we currently conduct our vegetation surveys in summer, we can verify our identifications by returning in the Fall and winter and looking for fruits. The nice thing about iNaturalist is we can always go back and change our IDs, if necessary.
green ash friuts
Photo By: cbarron
Carolina ash friuts
Photo By: VTforester
For more plant resources checkout this guide on wetland plants:
https://www.ncwetlands.org/plantguide/
And useful keys through the herbarium: https://herbarium.ncsu.edu/keysetc.htm
Don't forget to check out our our iNaturalist page to see all the plants we've found so far!
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Celebrating Our Carolina Wetlands
Hello Wetland Supporters, I hope everyone had a wonderful American Wetlands Month in May and found an opportunity to get outside and explore a wetland. We enjoyed fantastic paddling events at Robertson Millpond Preserve and Lake Mayo, where participants experienced the beauty and importance of these unique ecosystems firsthand. Wetlands have also been in the news recently as the impacts of recent Supreme Court decisions on wetland protections continue to be evaluated. Two recent articles highlight what is at stake: Lisa Sorg in Inside Climate News, Supreme Court’s Limitation on Wetlands Protection Will Make Flooding Worse Jesse Gourevitch and Adam Gold, New Research Shows What’s at Stake When Wetlands Disappea r The central message of both articles is clear: the loss of wetlands leads to increased flooding and rising economic costs for communities. Research cited by Gourevitch and Gold found that wetland loss across the United States has increased residential flood insurance claim payments by an estimated $10.1 billion since 1985 — approximately 9% of all insured riverine flood losses nationwide. The authors also emphasize that policymakers must better recognize the economic value wetlands provide in reducing flood damage to homes and communities. According to the research, the flood-mitigation value of currently unprotected wetlands is estimated at $177 billion nationwide , with North Carolina accounting for approximately $4.6 billion of those benefits . This research reinforces what the Carolina Wetlands Association has long understood: healthy wetlands are essential infrastructure for resilient communities. Through support from the NC Land and Water Fund, Carolina Wetlands Association have received three grants to partner with vulnerable communities to assess flooding concerns and develop restoration plans that incorporate community input, scientific data collection, and hydrologic modeling to identify the most effective wetland restoration strategies. We are also excited to share that we recently received a fourth NC Land and Water Fund grant to begin our first restoration project at Stony Run in Harnett County. Stony Run Walkable Watershed Lumbee Cultural Center Wetland Restoration By working alongside communities and restoring wetland resources, we are helping reduce potential flood damage while also providing additional benefits such as improved water quality, recreation opportunities, shoreline stabilization, environmental education, and greater community resilience. So, the next time you explore a wetland, remember that healthy wetlands mean healthy communities — and your support plays an important role in protecting these valuable ecosystems. Wetlands truly do matter. Best, Rick Savage Executive Director
Wetland supporters enjoyed two memorable May paddling events, exploring North Carolina’s beautiful wetlands while spotting wildlife and learning from local experts.
May is American Wetlands Month - yes, an entire month to celebrate these ecologically diverse and economically important ecosystems. Wetlands account for 14% of the land area in North Carolina and almost 20% of South Carolina!