Swamp Holly Ilex decidua WalterS2 (State rare)    
Kingdom Plantae   >   Division Tracheophyta   >   Class Magnoliopsida   >   Order Celastrales   >   Family Aquifoliaceae   >   Genus Ilex   


Swamp Holly is a rare native holly that reaches its northern limits in Maryland. Swamp Holly is mostly restricted to the coastal plain but gets up to the fall line along the Potomac River. According to MD DNR Swamp Holly is restricted to "Bottomland hardwoods, hardwood swamps, rich alluvial terrace forests and woodlands...this species may be locally abundant but is rare to infrequent at most stations."


Swamp Holly is superficially similar to both Common Winterberry and Smooth Winterberry. The easiest way to differentiate between the three species is to first check to see if the sepals of either the flower or fruit is ciliate (having shorts hairs) or glabrous (smooth, no hairs). Common Winterberry is the only one of these three deciduous hollies that have ciliate sepals. Both Swamp Holly and Smooth Winterberry have glabrous sepals. To separate Swamp Holly from Smooth Winterberry you have to check the seeds found inside the berries. Smooth Winterberry seeds are smooth and lack ridges where as the seeds of Swamp Holly are distinctively ridged.

There are 38 records in the project database.

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[View seasonality details]
Swamp Holly blooming in St. Mary's County, Maryland (5/11/2009). Photo by Kerry Wixted. (MBP list)

Swamp Holly in Caroline Co., Maryland (7/15/2018). Identified by Jim Brighton. Photo by Bill Hubick. (MBP list)

Swamp Holly in Caroline Co., Maryland (5/1/2021). (c) Jim Brighton, some rights reserved (CC BY-NC). Photo by Jim Brighton. (MBP list)

Swamp Holly in Caroline Co., Maryland (7/15/2018). Photo by Jim Brighton. (MBP list)

Fruiting Swamp Holly in the Carolina Sandhills NWR, North Carolina (10/21/2012). Photo by Will Stuart. (MBP list)

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