The Chesapeake Bay Watershed has considerable concentrations of

poultry farms (Figure 1). Over ten years ago, Mid-Atlantic poultry

producers began planting strategically placed perennial grasses,

shrubs and trees around their farms (Figure 2). Recent studies

demonstrate that vegetative environmental buffers (VEBs) take up

ammonia (Patterson 2006), capture dust particles (Parker 2011)

and reduce downwind odors thereby improving neighbor relations.

VEBs can also provide visual screens for poultry operations.

As a relatively low cost technology, VEBs can improve air quality

in a variety of ways. Native grasses (especially warm season) are

ideal for this purpose because they:

• Grow well during the summer when the tunnel fans are most

active and higher temperatures increase ammonia volatilization.

• Filter dust and odors.

• Do not limit fan performances (Hong 2016).

• Are resistant to deer damage.

Species diversity: This study’s objective is to expand the number of

native grasses (species and/or varieties) available to conservation

planners. The study investigated 10 different grass species

(including 12 varieties) for survival and size.

Methods Conclusions

Mid-Atlantic Native Grasses Tolerant of Poultry Farm EmissionsShawn Belt, Horticulturist

U.S. Department of Agriculture, Natural Resources Conservation Service (NRCS), Norman A. Berg National Plant Materials Center,

Beltsville, Maryland

Table 1 Grasses Tolerant of Poultry Farm Emissions

References

Studies were conducted from 2010 – 2017 at 14 different locations

(Figure 2) to evaluate growth and survival near sidewall, single,

and double tunnel ventilation fans (Figures 3 and 4).

Optimally, grasses were planted in the rows closest to the fans,

succeeded by deciduous woody and then evergreen plants (Figure

3). Due to limited resources, controls were planted and monitored

at only one farm. Drip irrigation was used to improve plant

survival in the harsh conditions associated with high temperatures

and windspeeds at the fan outlets.

Plant survival and size evaluations occurred annually (autumn).

To be deemed successful, a planting should have a survival rate of

at least 60% over two growing seasons, with a minimum planting

size of at least 10 plants on three different farms.

1. Patterson, P., Adrizal., A., Hulet, R., Bhates, R., Myers, C.,

Martin, C., Shocker, R., van der Grinten, M. 2006. Plant

Foliar Nitrogen and Temperature on Commercial Poultry

Farms in Pennsylvania. Proceedings of the Workshop on

Agricultural Air Quality. P 453-457.

2. Hong, L., Zhang, C., Collier, S., Brown, W., Moyle, J., 2016.

Assessment of Fan Performances Affected by Vegetative

Environmental Buffers. Poster Session presented at the

Annual Convention of the American Society of Agriculture

Biological Engineering, Orlando, Florida.

3. Parker, B, Malone, G., Walter, W. 2011. Vegetative

Environmental Buffers for Reducing Downwind Odor and

VOCs from Tunnel-Ventilated Swine Barns. ASABE

Annual International Meeting. Louisville, KY. Paper:

1110791.

Plant Survival: Four of the ten different plant species tested (40%) had

survival percentages above 60% over a two year period. Six of the ten

species tested (60%) were intolerant of poultry farm emissions and

had survival percentages below 60%. One promising plant, Giant

Cane, deserves further testing to determine emission tolerance in mesic

or wet soils.

Ventilation fan type: Five different varieties tolerated double and single

tunnel fan emissions, and an additional 3 varieties tolerated single fan

emissions. It is assumed that plants that tolerated single or double

tunnel fan emissions would also tolerate the lower velocity side wall

fans, but these were not extensively tested.

Distance between fans and plantings: Grasses were successfully

established as close as 20 feet from single bank and double bank

ventilation fans. This allows producers additional flexibility for

placement of VEBs where space is limited.

Introduction ResultsThis study confirmed that four native grass species (eight

varieties) out of the ten species and 12 varieties tested can be

successfully used in VEBs for ameliorating air and water quality

concerns. As a group, halophyte (salt tolerant) grasses were

especially tolerant, making up seventy-five percent of the tolerant

species. As a result of this study, additional grass

species/varieties have been added to NRCS conservation practice

specifications and fact sheets that are used by conservation

planners when considering plants for mitigating poultry

emissions.

Figure 1. Broiler Production in the Chesapeake Bay Watershed

2007 (Nat’l. Agricultural Statistical Service)

Common Name - Variety Farm* Fan Dist. (ft.) Fan Type** # tested Survival %

Big Bluestem 136

• Niagara E,F 20-40 T 88 48

• OZ-70 G, H 20-40 T 48 43

Giant Cane A, C, F, G, H 25 T, T² 47 35%

Emory's Sedge C, D, H 30 T² 17 0%

Coastal panicgrass¹

• Atlantic B, E 30 T 24 100%

Switchgrass¹ 160 95%

• Timber B, E, F, G 15 - 40 T, T² 22 100

• Kanlow B, E, F, G 15 - 40 T, T² 27 100

• Northwind B, E, F, G 15 - 40 T, T² 81 100

• Thundercloud B, E, F, G 15 - 40 T, T² 30 73

Florida Paspalum

• Mid-Atlantic C, D, E, F 20 T² 64 0%

Silver Plumegrass H, M 20 T, T² 2 0%

Prairie Cordgrass¹

• Southhampton F, J 20 T 31 100%

Eastern Gama Grass 32 63%

• Highlander H 20 T, T² 11 0

• Meadowcrest F 18 T 9 100

• Pete C, N 20 T, T² 12 92

Northern Sea Oats Grass F, H, M 20-45 T 25 0%

* Farm Locations correspond to Figure 2

** Ventilation Fan Type T – Single Fan Bank, T² - Double Fan Bank

¹ Halophyte (salt tolerant) species

Green font plant varieties are recommended for use

Figure 4. Double fan bank showing switchgrass intercepting

emissions (denoted by blue arrows) from being pushed up and off

the farm by prevailing winds.

Figure 2. Chesapeake Bay

Watershed Test Farm Locations

Figure 3. Vegetative Environmental Buffer Design

and Benefits

Common Name Botanical Name Conclusion/Notes

Big Bluestem Andropogon gerardiiWarm-season grass,

intolerant of emissions

Giant Cane Arundinaria gigantea

Cool season, very Tall,

intolerant of emissions except

in wet soils

Emory’s Sedge Carex emoryii Intolerant of emissions

Coastal PanicgrassPanicum amarum var.

amarulum

Warm season, tolerant of

emissions but short lived

Switchgrass Panicum virgatum

Warm season, tough,

adaptable, tolerant of

emissions

Florida Paspalum Paspalum floridanumWarm season, established

well but very short lived

Silver Plumegrass Saccharum alopecuroidesWarm-season, tall, intolerant

of emissions

Prairie Cordgrass Spartina pectinata

Cool season, tolerant of

emissions, tolerates highly

saline hard water discharge

areas

Eastern Gama Grass Tripsacum dactyloides

Warm season, short, tolerant

of emissions except in double

fan areas

Sea Oats Grass Uniola paniculataCool season grass, Intolerant

of emissions

Table 2 Recommended Grass Species and Conclusions

Shade

Poultry Farm

Visual Screen Native Grasses

Prevailing Winds

Emissions

Green Font species recommended for useAdapted from G. Malone University of Delaware