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Unknown @ USDA-NRCS PLANTS database
AUTHORSHIP AND CITATION:
Hauser, A. Scott. 2006. Morella pensylvanica. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us/database/feis/plants/shrub/morpen/all.html .
Updates: On 26 February 2018, the scientific name of this species was changed in FEIS from: Myrica pensylvanica
to Morella pensylvanica. The map was also added.
Myrica pensylvanica Mirbel (Myricaceae) [5,18,28,32,69,74,77,82]
NRCS PLANT CODE :
The scientific name of northern bayberry is Morella pensylvanica (Mirbel) Kartesz [46,90]. Where their ranges overlap, northern bayberry may hybridize with wax myrtle (M. cerifera) and southern bayberry (M. heterophylla) .
FEDERAL LEGAL STATUS:
No special status
Information on state-level protected status of plants in the United States is available at Plants Database.
Northern bayberry is a native species, occurring from Ontario east to Nova Scotia and south to Ohio and North Carolina [5,18,32,46,69,74,77,82].
|Distribution of northern bayberry. 1977 USDA, Forest Service map digitized by Thompson and others .|
FRES13 Loblolly-shortleaf pine
FRES41 Wet grasslands
STATES/PROVINCES: (key to state/province abbreviations)
Northern bayberry is listed as a dominant species in the following locations and vegetation classifications:North Carolina:
Northern bayberry is codominant on coastal sand dunes north of Nag's Head 
Northern bayberry/common reed (Phragmites australis) at Robins Island (Long Island) 
Northern bayberry is a perennial, low-growing, upright deciduous shrub [18,32,73,82,90]. It is stiffly branched [32,69,82] and typically 5 to 7 feet (1.5-2 m) tall [32,69,82,90], but may grow up to 15 feet (4.5 m) in height . Northern bayberry commonly grows on sand dunes and impoverished soils, where it is considerably shorter than 5 to 7 feet (1.5-2 m) tall . Growth habitat is clonal . Leaves are alternate, 3 inches (8 cm) long and 1 inch (2.5 cm) [69,82] wide, and crowded toward the end of the branch [77,82]. Flowers are small, inconspicuous , and grow on the old wood below the current leaf-bearing tips [74,82]. Unisexual flowers occur on different plants . The fruits are densely hairy, spherical drupes, 3.5 to 5.5 mm in diameter, that are covered in a wax-like coating [18,29,34].
Rhizomes/roots: Northern bayberry is rhizomatous [12,18,28,49]. In the Pine Barrens of New Jersey, northern bayberry is mainly found in the pitch pine (Pinus rigida) transition community, but may occur in isolated patches in upland areas. In the Pine Barrens, 1 or more aerial northern bayberry stems arise from a rhizome that is 0.19 to 0.5 inch (5-13 mm) in diameter. Northern bayberry generally occurs in soil where an Ao horizon has formed. The rhizomes of northern bayberry may be completely in the Ao horizon or partly in it and partly in the top 0.5 inch (13 mm) of the A1 horizon. Short roots grow along the rhizome, with roots as long as 12 inches (30 cm) occasionally found. Roots may extend as deep as 20 inches (50 cm) in Pine Barrens transition communities and as much as 24 to 30 inches (60-76cm) in upland communities .
Northern bayberry occurs in soils with low concentrations of phosphorus and nitrogen. Northern bayberry plants form cluster roots in these soils. This enhances their ability to uptake phosphorus and nitrogen on nutrient-poor soils. Cluster roots are dense assemblages of determinate rootlets that occur along lateral roots in close longitudinal rows, produce abundant root hairs, and resemble a "bottle brush" [44,81].
Cluster roots of northern bayberry were found at 11 sites in Maine and comprised 6.3% to 20.4% of fine root biomass. Northern bayberry cluster roots occurred in a wide range of substrates including mineral soils and organic soils that had litter depths from 0 to 0.8 inch (0-2 cm), organic matter content from 4.4% to 52.9%, and extractable soil phosphorus from 3.0 to 40.4 mg/kg .
Physiology: Northern bayberry seedlings are not flood tolerant . Mature plants are extremely drought tolerant .
Nitrogen fixation: Northern bayberry is a nitrogen-fixing shrub [4,10,14,31,44,47,57]. Plants in the field are infected by Frankia spp. actinomycetes [4,9,10,14,60].
In a controlled experiment, 1-year old northern bayberry plants associated with Frankia spp. had significantly (p<0.05) greater above- and belowground biomass than those not infected by Frankia spp. Northern bayberry plants associated with Frankia spp. had an average above- and belowground biomass of 35.38 and 14.76 grams, respectively, while plants unassociated with Frankia spp. had an average above- and belowground biomass of 10.10 and 5.04 grams, respectively .
In dune sands of the northeastern United States, it is estimated that northern bayberry adds 16 to 32 kg of nitrogen/ha/year to nitrogen-poor soils . This is a substantial nitrogen addition, given that dune sands along Nantucket Island, Massachusetts, average under 11 g/m² available nitrogen .RAUNKIAER  LIFE FORM:
Pollination: Northern bayberry is wind pollinated .
Breeding system: Northern bayberry is dioecious [18,29,34,38,65,69,77,82,90].
Seed production: Northern bayberry 1st produces fruit at 3 or 4 years of age and reaches maturity in 7 to 8 years of age . Fruits are "numerous" [12,52].
Seed dispersal: Northern bayberry seeds are dispersed by birds . Seeds pass through birds undamaged but with the wax coating removed, which is a pregermination requirement . Birds that disperse northern bayberry seeds come primarily from the families Mimidae, Turdidae, Bombycillidea and/or Sturnidae [84,94].
Seed banking: No information is available on this topic.
Germination: Northern bayberry seeds require stratification [29,90] and scarification [29,34]. Seeds germinate best when cold stratified for 90 to 150 days at 50 ºF (10 ºC) .
Seedling establishment/growth: No information is available on this topic.
Asexual regeneration: Northern bayberry reproduces by rhizomes [12,18,49].
Northern bayberry is found in swampy woods [50,82], around the coast on headlands, beaches, and occasionally in bogs [32,74], on the border of or in forests , and on dry hills, sand flats, and dunes . Northern bayberry also occurs in areas where topsoil has been completely removed, such as roadside cuts, railroad banks, and gravel pits .
Northern bayberry is described as a "marginal species," meaning that it occurs on both wet and dry sites .
Climate: Northern bayberry is common in the sand plain ecosystems of the northeastern United States. The climate of the region is characterized by cold winters and warm summers, with an average precipitation of 43 inches (1,100 mm). Approximately 50% of the precipitation falls from April to September [45,61]. Where northern bayberry grows in the Pine Barrens of Long Island, precipitation is evenly distributed throughout the year and averages 48.7 inches (1,237 mm) . Northern bayberry requires a minimum of 140 frost-free days .
Soil: Northern bayberry is adapted to many different soil types, but grows best on light-textured soils . It is well adapted to acidic, sandy, poorly drained, and low-fertility sites [26,29,49,52,71]. Northern bayberry is commonly found on soils with low concentrations of available nitrogen and phosphorus . It requires a soil pH of 5.5 to 7.8 
Northern bayberry is a dominant species on a barrier beach in South Kingstown, Rhode Island. It becomes dominant approximately 150 feet (45 m) from the dune crest. Soil characteristics where northern bayberry is dominant are :
|Sand grain size
A detailed soil analysis of Cape Cod National Seashore, Massachusetts, where northern bayberry is dominant, is provided in a review by Eberhardt and others .
Salt tolerance: Northern bayberry is tolerant of salt spray , growing relatively close to the ocean where salt spray is high and water availability is low. It showed no damage from salt spray in greenhouse trials and field experiments in a Massachusetts heathland [35,36].
Northern bayberry occurs along the South River of Maryland. The river is subjected to tidal fluctuations, and the salt content of the river ranges from 9.2% to 14.4% where northern bayberry occurs .SUCCESSIONAL STATUS:
Early to mid-seral: Northern bayberry is an early successional plant on dunes and impoverished coastal soils due in part to its nitrogen-fixing ability . In the Lake Erie region of Ohio, northern bayberry is an early successional species on open, sandy, or peaty soils . On the sea cliffs of Long Island, northern bayberry occurs in early- to mid-seral communities dominated by pitch pine. Good and Good  describe those seres as a "preforest" stage.
Northern bayberry is an early successional species along the northeastern coast. Areas colonized by northern bayberry undergo succession to other shrub communities characteristic of mature coastal heaths. Shrubs that follow northern bayberry along the successional gradient include black huckleberry (Gaylussacia baccata), bear oak (Quercus ilicifolia), groundsel-tree, and eastern poison-ivy (Toxicodendron radicans ssp. radicans). In areas near the coast and inland of the coast, northern bayberry gives way to rugosa rose (Rosa rugosa) and Carolina rose (R. carolina), respectively .
On Nantucket Island, Massachusetts, northern bayberry codominates with low sweet blueberry (Vaccinium angustifolium) and dwarf huckleberry (G. dumosa) in the 1st stage of mid-succession. It is preceded by a grass- (Schizachyrium ssp., Deschampsia ssp., and Festuca ssp.) dominated stage and followed by the 2nd mid-succession stage that is dominated by bear oak and the mature successional stage that is dominated by pitch pine .
Late-seral: Northern bayberry is an understory species in "climax" stands of Atlantic white-cedar (Chamaecyparis thyoides) in the Pine Barren swamps of southern New Jersey .
Fire: On the Southern Upland of southwestern Nova Scotia, northern bayberry occurs on burned sites of varying ages. Northern bayberry occurred with less than 5% cover on a 10-year-old burn, on a 22-year-old burn with cover of approximately 5%, and a 29-year-old burn with cover of 5% . On Peaks Island in Casco Bay, Maine, large-scale fires burned all or part of the island in 1934, 1936, and 1957. Most of the trees on the island (red spruce (Picea rubens), eastern white pine (Pinus strobus), and paper birch (Betula papyrifera)) were burned and killed. After vegetation sampling in 1962, northern bayberry was described as "conspicuous" (see Plant Response to Fire) .
Logging: At 3 locations on mainland Nova Scotia (Six Mile Bog, Four Mile Road, and Milton) northern bayberry was an early successional species on clearcut forests. At Six Mile Bog and Four Mile Road, northern bayberry had established 3 to 5 years following logging. At Milton, northern bayberry initiated growth 1 year following clearcutting .
Old fields: At the Audubon Nature Sanctuary in southwestern Connecticut, northern bayberry commonly gains dominance following a stage of herbaceous annuals and perennials in abandoned farmlands. The northern bayberry stage is followed by dominance of gray birch (Betula populifolia), eastern redcedar (Juniperus virginiana), black cherry (Prunus serotina), and white ash (Fraxinus americana) . Northern bayberry is of local importance on 30-year-old abandoned farmland dominated by pin oak (Quercus palustris) in the Hutcheson Memorial Forest, New Jersey . In Somerset County, New Jersey, northern bayberry is present on abandoned farmlands as young as 2 years old. It occurs in greatest numbers on fields abandoned for approximately 60 years .
Species displacement: In old fields on the New Jersey Piedmont, little bluestem (Schizachyrium scoparium) communities may be invaded and displaced by northern bayberry. Several factors contribute to northern bayberry displacement of little bluestem in old fields. First, vigorous vegetative sprouting of mature northern bayberry plants results in the enlargement of its area. Second, as northern bayberry invades little bluestem communities, increased shading can inhibit the growth of little bluestem seedlings and vegetative sprouts. Third, northern bayberry litter leachate may slightly inhibit little bluestem growth. Fourth, northern bayberry's ability to enrich the soil through nitrogen fixation may allow for establishment of later successional species that can further contribute to the displacement of little bluestem .
Displacement of little bluestem grasslands by northern bayberry clonal expansion was measured from 1980 to 1984 at the Gateway National Recreation Area, New York, utilizing aerial photography. Northern bayberry expanded into and displaced little bluestem communities at a rate of 4.08% per year during the study. In area, this translates to an increase of 610 m². The researchers attribute northern bayberry displacement of little bluestem to litter accumulation and shading .SEASONAL DEVELOPMENT:
Flowering dates of northern bayberry are presented below:
|New York||June |
|North Carolina||April |
|Atlantic coastline||April to May |
|Nova Scotia||June |
Fire regimes: Much of the research on northern bayberry focuses on its presence along the coastline in dune communities, where the occurrence of fire is low. Due to a long history of anthropogenic ecosystem interference in the northeastern United States, the fire history of the area is largely unknown. Northern bayberry is a minor species in the Pine Barrens of New Jersey. The Pine Barrens have burned repeatedly, at intervals of 10 to 30 years . Northern bayberry is common and dominant in several locations at Cape Cod, Massachusetts. Several fire history studies of Cape Cod have been conducted and are presented below.
Fires were likely an important factor in maintaining Atlantic coastal woodlands, heathlands, and grassland communities prior to European settlement. There is little fire history for Cape Cod prior to the mid-19th century; however, fire frequency in the area generally increased with land clearing associated with colonial settlement. Fires were common on Cape Cod from the mid-19th to the early 20th century, with primary ignition caused by railroads . From 1897 to 1962 there have been at least 31 fires at Cape Cod National Seashore, some of which have exceeded 74 acres (30 ha). Since the establishment of Cape Cod National Seashore in 1961, no large fires have occurred due to fire exclusion . Motzkin and others  investigated the fire history of Cape Cod and reported that there was historical evidence of fire in 38.5% of the sites.
The following table provides fire return intervals for plant communities and ecosystems where northern bayberry is important. Find fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find Fire Regimes".
|Community or Ecosystem||Dominant Species||Fire Return Interval Range (years)|
|maple-beech||Acer-Fagus spp.||684-1,385 [11,91]|
|sugar maple||Acer saccharum||>1,000 |
|birch||Betula spp.||80-230 |
|Atlantic white-cedar||Chamaecyparis thyoides||35 to >200 |
|northern cordgrass prairie||Distichlis spicata-Spartina spp.||1-3 |
|beech-sugar maple||Fagus spp.-Acer saccharum||>1,000 |
|California steppe||Festuca-Danthonia spp.||<35 [51,66]|
|northeastern spruce-fir||Picea-Abies spp.||35-200|
|black spruce||Picea mariana||35-200|
|conifer bog*||Picea mariana-Larix laricina||35-200|
|red spruce*||Picea rubens||35-200|
|shortleaf pine||Pinus echinata||2-15|
|shortleaf pine-oak||Pinus echinata-Quercus spp.||<10 |
|pitch pine||Pinus rigida||6-25 |
|loblolly pine||Pinus taeda||3-8|
|loblolly-shortleaf pine||Pinus taeda-P. echinata||10 to <35|
|Virginia pine||Pinus virginiana||10 to <35|
|Virginia pine-oak||Pinus virginiana-Quercus spp.||10 to <35 |
|aspen-birch||Populus tremuloides-Betula papyrifera||35-200 [16,91]|
|black cherry-sugar maple||Prunus serotina-Acer saccharum||>1,000|
|northeastern oak-pine||Quercus-Pinus spp.||10 to <35|
|white oak-black oak-northern red oak||Quercus alba-Q. velutina-Q. rubra||<35|
|northern pin oak||Quercus ellipsoidalis||<35|
|bear oak||Quercus ilicifolia||<35|
|bur oak||Quercus macrocarpa||<10|
|northern red oak||Quercus rubra||10 to <35|
|black oak||Quercus velutina||<35 |
|Month of fire||Cover (%)||Frequency (%)|
Regular burning of old fields dominated by little bluestem at the Connecticut College Arboretum reduced the cover and frequency of northern bayberry. Burning began in 1968 on 2 separate plots, approximately 40 years after agricultural abandonment. Prescription burning on Plot A occurred from 1968 to 1976 and in 1978, 1980, 1983, and 1985. Prescription burning on Plot B occurred from 1968 to 1975 and in 1978, 1980, 1983, and 1985. Burning on both plots took place during early April when northern bayberry was still dormant. Cover and frequency of northern bayberry in 1967 prior to burning and reduced cover in 1985  were:
|Plot A||Plot B|
In Massachusetts, prescription burning of northern bayberry during 3 different seasons, in different ecosystems, and at various intervals on Nantucket, Martha's Vineyard, and Cape Cod produced myriad results. Burning trials were conducted on either coastal heathlands (Tom Nevers and Sesachacha sites) or sandplain grasslands (Ram Pasture, Sanford Farm, and Katama sites) from 1982 to 1995. Northern bayberry was top-killed in all burning trials. Prescription fires in both ecosystems were generally ignited as strip headfires with flame lengths not exceeding 6 feet (2 m) in grasslands and 30 feet (10 m) in heathlands. In the heathlands, northern bayberry remained relatively constant or decreased when prescription burned during fall and spring. In the sandplain grasslands, northern bayberry decreased on 4 of 5 burned plots . Details are provided below.
Burning heathlands: At Tom Nevers, northern bayberry stands were burned in 1985, 1988, and 1992 during October and in 1985, 1987, 1989, and 1992 during April. In 1985, cover and frequency of northern bayberry on October burn plots was 2% and 23%, respectively. In 1992, cover remained at 2% and frequency increased to 30%. In 1985, cover and frequency of northern bayberry on April burn plots was 5% and 47%, respectively. In 1994, cover and frequency were reduced to 2% and 37%, respectively. At Sesachacha, northern bayberry communities were burned in 1988, 1991, and 1994 during April. In 1989, cover and frequency was 1% and 9%, respectively. By 1995, northern bayberry cover was reduced to <1% and frequency to 7% .
Burning grasslands: At Ram Pasture, northern bayberry was burned biennially from 1983 to 1995 on plots designated as August burn and April burn. On August burn plots, northern bayberry was reduced from 9% cover and 50% frequency in 1983 to 3% cover and 13% frequency in 1995. In plots burned in April, northern bayberry was reduced from 4% cover and 33% frequency in 1982 to 2% cover and 30% frequency in 1995. The only instance where northern bayberry increased following burning was at Katama, Martha's Vineyard. At this location, northern bayberry was burned during October in 1986, 1987, and 1992. In 1986, cover and frequency were 4% and 17%, respectively. Two years following the last burn, 1994, cover and frequency had increased to 7% and 20%, respectively .
Burning/mowing grasslands: Northern bayberry was mowed prior to burning on 2 plots at Sanford Farm. On Plot 1, northern bayberry was mowed and burned in June 1986, March 1987, March and June 1989, April 1991, September 1992, April 1993, and March and September 1995. In 1986, cover and frequency of northern bayberry were 12% and 46%, respectively, and reduced to 5% and 23%, respectively, in 1994. On Plot 2, northern bayberry was mowed and burned in August 1986, May 1987, March 1989, and February and March 1990. On Plot 2, northern bayberry decreased from 16% cover and 42% frequency in 1986 to 11% cover and 42% frequency in 1990 . For more information on this study, see the Research Project Summary Vegetation change in grasslands and heathlands following multiple spring, summer, and fall prescription fires in Massachusetts.FIRE MANAGEMENT CONSIDERATIONS:
Birds: Northern bayberry fruit remains on the plant well into winter when above accumulated snow, making it accessible to northern bobwhite, ruffed grouse, ring-necked pheasant, and numerous songbird species [38,90]. During fall migration, especially along the east coast of the United States, songbirds cease eating insects and begin eating primarily fruit. Block Island, Rhode Island, is a stopping point for yellow-rumped warblers during fall migration. While on Block Island, yellow-rumped warbler diets consist mainly of northern bayberry fruits . On the New Jersey Piedmont, northern bayberry fruit is an important source of food for birds in the families Mimidae, Turdidae, Bombycillidea, and/or Sturnidae [84,93,94].
Palatability/nutritional value: Northern bayberry plant tissue and litter, collected on Nantucket Island in mid-June and mid-September, was analyzed for nitrogen content. Little difference was observed between dates, and thus only the mean nitrogen content was reported. The percent nitrogen content (x±s x) of northern bayberry tissue and litter was 1.59±0.13 and 1.55±0.10, respectively .
Cover value: Northern bayberry retains part of its leaf cover throughout the winter, providing shelter for game and nongame animals throughout the year . The northern harrier, rare in Massachusetts, has been observed roosting at Barney's Joy Point in dense shrub/grasslands codominated by northern bayberry .VALUE FOR REHABILITATION OF DISTURBED SITES:
On Sable Island, Nova Scotia, northern bayberry showed tolerance to experimental natural gas contamination .
On strip-mine spoil banks in southern Indiana that were amended with lime, 1- to 2-year-old transplanted northern bayberry seedlings had low survival rate at all lime levels. To raise the pH level of the acid mine spoils, lime was added at rates of 0, 12.5, 25, and 39 tonnes/ha. At the 4 levels, northern bayberry survival rate 15 months following planting was 0%, 33.0%, 12.5%, and 26.7%, respectively. Combining all plots, northern bayberry survival rate was 18.1%, which was the lowest survival rate of any plant used in the study [41,42].
There was 1 northern bayberry cultivar ('Wildwood') available as of 2006 .OTHER USES:
The Micmac and Malecite tribes of Canada's Maritime Provinces used northern bayberry stems, leaves, berries, and roots for medicinal purposes .OTHER MANAGEMENT CONSIDERATIONS:
Herbicides: Several researchers [76,95] discuss the effects of the herbicides azafenidin, pendimethalin, simazine, and sulfometuron on the growth rate of northern bayberry at the Southeast Purdue Agricultural Center, Indiana. Herbicides were used to control crabgrass (Digitaria spp.), horseweed (Erigeron canadensis), giant foxtail (Setaria faberii), and yellow foxtail (S. glauca).
Mowing: On the sandplain grasslands of Nantucket Island, Massachusetts, northern bayberry cover and frequency were decreased 2 years after an August mowing compared to premowing levels. Mowing occurred on 4 August 1983, and all vegetation was mowed within 2 inches (5 cm) of the ground. Most species had largely completed summer growth, but were still green during the August mowing. In 1983, prior to mowing, cover and frequency of northern bayberry were 5% and 28%, respectively. When the mowed plot was again sampled in July and August of 1985, northern bayberry cover and frequency were reduced to 2% and 24%, respectively .
Mowing northern bayberry 6 times from 1985 to 1992 at Tom Nevers, Nantucket Island, did not change cover or frequency. Northern bayberry was mowed in July and September 1985, October 1988, February 1990, and March 1992. In 1985, cover and frequency of northern bayberry were 4% and 40%, respectively, and remained the same when sampled again in 1994 .
Plant facilitation: Northern bayberry had a positive influence on the growth, reproductive output, and seedling recruitment of the sand dune species seaside goldenrod (Solidago sempervirens) and American beachgrass under the shrub's canopy at Cape Cod National Seashore. Seaside goldenrod under northern bayberry canopies was significantly taller (p<0.0001), had a greater number of leaves (p<0.001), more biomass (p<0.0009), was more likely to be in flower (p<0.0001), had more flowering stems (p<0.002), more flowerheads (p<0.01), more florets per flowerhead (p<0.01), and established more seedlings (p<0.001). American beachgrass under northern bayberry was significantly taller (p<0.0002), had a greater number of adult stems (p<0.05), more biomass (p<0.001), was more likely to be in flower (p<0.0007), had more flowering stems (p<0.0005), more flowers (p<0.0001), and more seeds (p<0.02). Seaside goldenrod and American beachgrass under the canopy of northern bayberry grow and reproduce better because soil temperatures are lower, plants are shielded from solar- and wind-driven water loss and are not as subjected to sand movement, and the availability of soil nutrients is higher under the canopy .On Nantucket Island, young (5-8 years) and old (12-25 years) pitch pine and young (3-6 years) Japanese black pine (P. thunbergii) grew more in height annually when located within northern bayberry clumps. Young pitch pine trees associated with northern bayberry on average increased 5.0 inches (12.7 cm) a year compared to 4.2 inches (10.7 cm) for trees not associated with northern bayberry. Old pitch pines associated with northern bayberry on average increased 5.1 inches (12.9 cm) a year compared to 4.4 inches (11.2 cm) for trees not associated with northern bayberry. Young Japanese black pines associated with northern bayberry on average increased 8.1 inches (20.8 cm) a year compared to 7.7 inches (19.5 cm) for trees not associated with northern bayberry. Increased growth by pitch pine and Japanese black pine in clumps of northern bayberry was attributed to nitrogen fixation .
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