FS727 - Understory Plants for Riparian Forest Buffers

FS727

1998

Understory Plants for Riparian Forest Buffers

by Bob Tjaden & Glenda M. Weber

The following tables list understory trees and shrubs appropriate for riparian forest buffers. Understory trees and shrubs are tolerant to shade and are an important structural component of any forest. Some shrubs, such as rhododendron and some blueberries are also adapted to the low-light conditions of the forest understory, but more are adapted to the buffer's edge. The edge might be next to the water or next to an upland area. Most of the shrubs listed prefer moist growing conditions and are good choices for areas that filter water flow. Shrubs that prefer drier sites include witch hazel, grey dogwood, and rose-bay rhododendron.

Including understory trees and shrubs in a riparian forest buffer planting increases the structural diversity of the buffer by providing layers of vegetation. This increases biodiversity and enhances both the water quality and wildlife habitat attractiveness of the buffer.

Riparian Understory Shrubs
	Region¹	Wildlife Value²	Light Preference	Flood Tolerance³	Growth Rate	Deciduous/ Evergreen	Rooting
Arrowwood viburnum	CP,P,M	Medium	full sunlight partial shade	Medium	Medium	Deciduous	Shallow
Bayberry	CP	High	full sunlight	High	Medium	Deciduous/ Evergreen	Shallow
Blackhaw	P,M	High	full sunlight partial shade	High	Medium	Deciduous	Shallow
Buttonbush	CP,P,M	Medium- High	full sunlight partial shade	High	Medium	Deciduous	Shallow
Common ninebark	CP,P	Medium	full sunlight	High	Fast	Deciduous	Shallow
Elderberry	CP,P,M	Very high	full sunlight partial shade	High	Fast	Deciduous	Shallow
Grey dogwood	P,M	Very high	full sunlight partial shade	Low	Medium	Deciduous	Shallow
Highbush blueberry	CP,P	Very high	full sunlight partial shade	High	Slow	Deciduous	Shallow
Inkberry	CP	High	full sunlight partial shade	High	Slow	Evergreen	Shallow
Maple-leaf virburnum	P,M	High	partial shade shade	Low	Medium- Slow	Deciduous	Shallow
Pinxterbloom azelea	CP,P	Low	partial shade shade	High	Slow	Deciduous	Shallow
Possumhaw	P,M	High	full sunlight partial shade	High	Medium	Deciduous	Shallow
Pussy willow	P,M	Medium	full sunlight	Medium	Fast	Deciduous	Shallow
Red chokeberry	CP	Medium	full sunlight partial shade	High	Slow	Deciduous	Shallow
Red osier dogwood	CP,P,M	High	full sunlight partial shade	High	Fast	Deciduous	Shallow
Rosebay rhododendron	CP,P,M	Low	partial shade shade	Low	Slow	Evergreen	Shallow
Silky dogwood	P,M	High	full sunlight partial shade	Medium	Fast	Deciduous	Shallow (good bank stablizer)
Smooth alder	P,M	Medium	full sunlight partial shade	High	Medium- Fast	Deciduous	Shallow
Speckled alder	M	Medium	full sunlight	High	Fast	Deciduous	Shallow
Spicebush	CP,P,M	Very high	partial shade shade	Medium	Fast	Deciduous	Deep lateral
Swamp azalea	CP,P	Low	full sunlight partial shade	High	Medium	Deciduous	Shallow
Swamp leucothoe	CP,P	Low	partial shade shade	Medium	Slow	Evergreen	Shallow
Sweet pepperbush	CP,P,M	High	full sunlight partial shade	High	Medium	Deciduous	Shallow
Virginia sweetspire	P,M	Low	full sunlight partial shade	High	Medium- Slow	Deciduous	Shallow
Winterberry	CP,P	High	full sunlight partial shade	High	Slow	Deciduous	Shallow (seasonally flooded areas)
Witch-hazel	P,M	Low	full sunlight partial shade	Low	Medium	Deciduous	Deep lateral
Riparian Understory Trees
	Region¹	Wildlife Value²	Light Preference	Flood Tolerance³	Growth Rate	Height (feet)	Rooting
American holly	CP,P	High	partial shade	Medium- Low	Slow	30-40'	Taproot
American hornbeam	P,M	Medium- High	partial shade shade	Medium- Low	Slow	30-40'	Deep lateral
Boxelder	P,M	Medium	full sunlight	High	Very fast	>50'	Deep lateral
Flowering dogwood	CP,P,M	Medium	full sunlight partial shade shade	Low	Slow	30-40'	Shallow
Hawthorn	CP,P,M	High	full sunlight	Low- Medium	Medium	<30'	Shallow
Hophornbeam	CP,P,M	Medium	full sunlight partial shade shade	Low	Slow	<30'	Shallow
Pawpaw	P	Very high	partial shade shade	Low- Medium	Slow	30-40'	Deep lateral
Persimmon	CP,P	Very high- High	full sunlight	Medium	Slow	<50'	Deep taproot
Redbud	P,M	Medium	partial shade	High	Slow	<50'	Shallow
Sassafras	CP,P,M	High	full sunlight	Low	Fast	<50'	Shallow
Shad-bush	P,M	High	partial shade shade	High	Slow	30-40'	Shallow
Sweet-bay magnolia	CP,P	Very low- Low	partial shade	Medium	Medium	<30'	Deep lateral

P = "Piedmont", CP = "Coastal Plain", and M = "Mountains"
food source for wildlife
High = "tolerates flooding/high water", and Low = "does not tolerate flooding/high water"

" For a list of shrub sources, refer to "PLANT AND SEED SUPPLIERS".

References
U.S. Department of Agriculture Forest Service. 1997. Chesapeake Bay Riparian Handbook.

FS727

P97/R98

Understory Plants for Riparian Forest Buffers

by
Robert L. Tjaden
Regional Extension Specialist
Natural Resources
Wye Research and Education Center

Glenda M. Weber
Faculty Extension Assistant
Natural Resource Management
Wye Research and Education Center

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