SPECIES: Juniperus virginiana
|Photos courtesy USDA-NRCS PLANTS Database / Herman, D.E. et al. 1996. North Dakota tree handbook. USDA NRCS ND State Soil Conservation Committee; NDSU Extension and Western Area Power Admin., Bismarck, ND.|
AUTHORSHIP AND CITATION:
Anderson, Michelle D. 2003. Juniperus virginiana. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed.us/database/feis/ .
Sabina virginiana (L.) Antoine 
NRCS PLANT CODE :
The currently accepted scientific name of eastern redcedar is Juniperus virginiana L. (Cupressaceae) [33,36,53,54,55,68,71,76,101,110,114,118,129,130]. The two recognized varieties of this species are J. virginiana var. virginiana [71,129] and southern redcedar (J. virginiana var. silicicola (Small) J. Silba) . Adams  described southern redcedar as a variety of eastern redcedar based on similarity of morphological characteristics and volatile leaf oils. However, southern redcedar has previously been described and is still accepted by some authors as a distinct species, J. silicicola . This species summary refers to both varieties of eastern redcedar; information specific to variety is noted.
Hybrid swarms of eastern redcedar and creeping juniper (J. horizontalis)
occur on the coast of Maine and in the Driftless Area according to morphological,
terpene, electrophoretic, and cytological data analysis [44,96,106]. Based on
morphological variation, hybrid swarms of eastern redcedar and Rocky Mountain juniper
(J. scopulorum) occur in the Texas panhandle and the northern Great Plains
[45,60,61,65]. Also based on studies of morphological characteristics, hybrid swarms
of eastern redcedar and Ashe juniper (J. ashei) reportedly occur in Oklahoma,
Texas, and Missouri [59,62,65]. However, in a study of terpenoids, Adams and Turner 
found no evidence of hybridization between eastern redcedar and Ashe juniper.
FEDERAL LEGAL STATUS:
No special status
The Flora of North America
provides a distributional map of eastern redcedar and its infrataxa.
FRES10 White-red-jack pine
FRES12 Longleaf-slash pine
FRES13 Loblolly-shortleaf pine
FRES32 Texas savanna
FRES33 Southwestern shrubsteppe
FRES34 Chaparral-mountain shrub
FRES36 Mountain grasslands
FRES37 Mountain meadows
FRES38 Plains grasslands
STATES/PROVINCES: (key to state/province abbreviations)
Where eastern redcedar dominates, species diversity is commonly low . Pure stands of eastern redcedar occur throughout its range, primarily on dry uplands or abandoned farmlands [63,79], though hardwood species may also occur on these sites . In southern Appalachian montane cedar-hardwood woodlands, eastern redcedar occurs with bluestems (Andropogon spp.), little bluestem, sedges (Carex spp.), panicgrass (Dichanthelium spp.), yellow honeysuckle (Lonicera flava), cliff stonecrop (Sedum glaucophyllum), white ash (Fraxinus americana), eastern redbud (Cercis canadensis), slippery elm (Ulmus rubra), honey-locust (Gleditsia tricanthos), chinkapin oak (Q. muehlenbergii), chestnut oak (Q. prinus), pignut hickory (Carya glabra), and mockernut hickory (C. tomentosa) [24,111]. Pure stands are also common in the northern Great Plains, though the stands may eventually be invaded by other woody species .
In the prairie ecosystem, common associates of eastern redcedar include little bluestem, big bluestem (A. gerardii var. gerardii), sideoats grama (Bouteloua curtipendula), blue grama (B. gracilis), western wheatgrass (Pascopyrum smithii), indiangrass (Sorghastrum nutans), switchgrass (Panicum virgatum), prairie dropseed (Sporobolus heterolepsis), gray goldenrod (Solidago nemoralis), sedges, flowering spurge (Euphorbia corollata), smooth sumac (Rhus glabra), leadplant (Amorpha canescens), poison-ivy (Toxicodendron radicans), common snowberry (Symphoricarpos albus), silver buffaloberry (Shepherdia argentea), chokecherry (Prunus virginiana), common juniper (J. communis), gray dogwood (Cornus racemosa), currants (Ribes spp.), and Rubus species [93,126].
Where stands of eastern redcedar are interspersed with grasslands, "cedar glades" may develop. Cedar glades are found in the Ozark region, north to Wisconsin, and east to Illinois and Kentucky. Though eastern redcedar dominates and may occur in almost pure stands in these glades [11,31,46,58,78], common associates in midwestern glade communities include little bluestem, big bluestem, broomsedge bluestem (Andropogon virginicus), hairy grama (B. hirsuta), sideoats grama, switchgrass, prairie Junegrass (Koeleria macrantha), indiangrass, dropseeds (Sporobolus spp.), blackjack oak, post oak (Q. stellata), white ash, winged elm (U. alata), fragrant sumac (Rhus aromatica), Carolina buckthorn (Frangula caroliniana), rusty blackhaw (Viburnum rufidulum), Alabama supplejack (Berchemia scandens), and common persimmon (Diospyros virginiana) [11,46,47,58,78]. In Kentucky cedar glades, eastern redcedar commonly occurs with big bluestem, little bluestem, purple threeawn (Aristida purpurea), indiangrass, nodding onion (Allium cernuum), Carolina larkspur (Delphinium carolinianum ssp. virescens), blue wild indigo (Baptisia australis), roundhead lespedeza (Lespedeza capitata), flowering spurge, spotted sandmat (Chamaesyce maculata), slenderstalk beeblossom (Gaura filipes), necklace gladecress (Leavenworthia torulosa), Michaux's gladecress (L. uniflora), little hogweed (Portulaca oleracea), bearded flatsedge (Cyperus squarrosus), and widowscross (Sedum pulchellum) . In Wisconsin cedar glades, common associates include little bluestem, big bluestem, flowering spurge, leadplant, hairy grama, Michaux's stitchwort (Minuartia michauxii var. michauxii), gray goldenrod, basswood (Tilia americana), gray birch (Betula populifolia), common juniper, and creeping juniper .
Classifications identifying eastern redcedar as a plant community dominant include those listed below:
New York 
North Carolina 
Eastern redcedar is a relatively long-lived evergreen that may reach 450+ years [29,36,114,124]. It has 2 distinct growth forms. The most familiar form is narrowly conical with its branches growing up and out at a sharp angle to form a compact tree. The 2nd form is broadly conical with branches that spread widely. Both forms can be found throughout eastern redcedar's range . Some authors describe the 2 forms in terms of age: young trees have the narrowly pyramidal or columnar shape with crowns becoming open and irregular as trees age . Others suggest differences in crown form are attributed to variety, with J.v. var. virginiana displaying the columnar form and J.v. var. silicicola more broadly conical to rounded [29,36,68].
Eastern redcedar has thin, fibrous bark [29,55,129] that is 0.3 to 0.64 inch (0.75-1.6 cm) thick [8,28,29]. Leaves of eastern redcedar are borne in 2 forms. On seedlings and new twigs, leaves are pointed and awl-shaped. On mature branches, closely overlapping scale-like leaves fit tightly against the twig in opposite pairs [46,124,129].
Eastern redcedar generally has a shallow, fibrous root system [8,124], though roots of mature eastern redcedar trees may penetrate 25 feet (7.6 m) and lateral roots may reach 20 feet (6 m) [26,141]. Eastern redcedar seedlings have penetrating taproots and may later develop a lateral taproot system [24,79]. The deep, early taproot is usually replaced by an extensive, shallow root system with age . Even 1st year seedlings begin developing a long fibrous root system, often at the expense of top growth . The root system may be deep where soil permits , but on shallow and rocky soils eastern redcedar roots are very fibrous and tend to spread widely . The development of a lateral taproot with age may also enable eastern redcedar to persist on outcrops and shallow soils .
Eastern redcedar seeds are borne in small, fleshy, berrylike cones [8,29],
with 1 to 4 seeds per cone [44,68,79,124]. Eastern redcedar cones or fruits
range from 0.12 to 0.33 inch (3-8 mm) long, with most 0.14 to 0.22 inch (3.5-5.5 mm)
long [44,63,68,129]. Within this range, J.v. var. silicicola
generally has smaller cone sizes than J.v. var. virginiana .
Seeds are 0.08-0.16 inch (2-4 mm) long [63,129].
RAUNKIAER  LIFE FORM:
Eastern redcedar reproduces solely by seed; there is no natural asexual regeneration. Eastern redcedar trees reach sexual maturity at approximately 10 years [29,79]. Reproductive activity may be influenced by tree size and site characteristics. A study in the Tennessee Valley found that in a managed parkland, 86% of eastern redcedar >4 inches (10 cm) dbh were reproductively active and the sex ratio was 1:1. In mature xeric forests on the rocky mountainsides only 41% of eastern redcedar >4 inches dbh were reproductively active, and the male:female sex ratio was 2.2:1. The likelihood of reproductive activity 1) was lower on the mountainside than in the parkland, 2) increased with tree diameter and height, 3) increased with diameter growth rate, and 4) decreased with shading by neighboring trees .
Breeding system: Eastern redcedar is dioecious [29,46,55,63,79,110,124,127]. Though rare, monoecious eastern redcedars have been found [55,110,124]. Male trees tend to be taller and have greater diameter growth than female trees, which may contribute to their success as pollen donors .
Pollination: Eastern redcedar pollen is wind-dispersed .
Seed production: Mature eastern redcedar trees produce some seeds nearly every year, but good crops occur only every 2 or 3 years [46,79,127]. Eastern redcedar produces most seed between the ages of 25 and 75, though seed production can occur in trees as young as 10 years and as old as 100+ years .
Seed dispersal: Eastern redcedar seed is dispersed by birds and small mammals [8,13,17,46,79,93,119]. As a result, seedling density is generally greater near trees or along fencelines that provide perching sites . Seeds pass through bird digestive tracts within 30 minutes of ingestion, suggesting many seeds will be deposited near their source trees rather than transported long distances. Seeds mature and are available to birds in winter and early spring when other food is scarce and populations of wintering birds are high .
Seed banking: No information is available on this topic.
Germination: Seeds that pass through animal digestive tracts and those that remain on the ground beneath the trees may germinate the 1st or 2nd spring after dispersal. Most germination of eastern redcedar seed occurs in early spring of the 2nd year after dispersal [46,79,129]. Delayed germination is caused by embryo dormancy and possibly by an impermeable seedcoat. Passage through an animal's digestive tract speeds seed germination .
Seedling establishment/growth: Most natural regeneration of eastern redcedar takes place on relatively poor hardwood or pine (Pinus spp.) sites, along fence rows, or in pastures that are not burned or mowed. Seedlings are commonly established in rather open hardwood stands, adjacent to older seed-bearing eastern redcedar trees . Eastern redcedar seedlings are shade intolerant, so survival is better under open stand conditions . If competition from an overstory is severe, eastern redcedar seedlings may not survive. Once established, however, eastern redcedar survives for extended periods under severe competition . Eastern redcedar seedling establishment may be improved following the removal of litter . On very dry sites, most seedlings are found in crevices, between layers of limestone, and in other protected places where the microclimate is most favorable [46,79]. Seedling development is relatively slow on these adverse sites, although eastern redcedar seedlings withstand drought well . Established seedlings are drought tolerant due to their taproot and relatively small leaf surface [46,132]. During the 1st year, seedlings do not produce much height growth but develop a long fibrous root system [46,79].
Eastern redcedar growth is relatively slow [46,63], though stem volume, sapwood, and heartwood growth rates of eastern redcedar increase when trees reach 15 to 20 years . Trees 20 to 30 years old are generally 18 to 26 feet (5.5-8 m) tall and 2 to 3 inches (5-7.5 cm) in diameter [46,63,79]. Mature trees typically reach 40-70 feet (12-21 m) tall, with a short bole 12 to 28 inches (30-71 cm) in diameter [46,55,63,79,79,86]. Growth rates of eastern redcedar depend largely on stand density, competition from other species, and site quality. These factors probably reflect competition for available soil moisture on most sites . On "good" sites , trees may reach 120 feet (36 m) tall and 4 feet (1.2 m) in diameter [46,79,82]. On dry sites in the prairie region, trees 110 years old are often less than 20 feet (6 m) tall [46,82]. On thin soils where growth is particularly slow, eastern redcedar may have diameters <2 inches (5 cm) after 50 years . An example of aboveground biomass and productivity from 3 Kansas eastern redcedar stands is presented below :
|Total aboveground biomass
|Litter fall production
|Annual aboveground net primary productivity
Increased stand density generally results in taller eastern redcedar trees .
There is no natural asexual reproduction in eastern redcedar. It does not
resprout after complete cutting or burning [29,79,132].
Elevation and aspect: Eastern redcedar occurs from sea level to 5,000 feet (1,524 m) in elevation [29,111]. Although the most desirable elevation is not clearly delineated, eastern redcedar is found most often growing between 100 and 3,500 feet (30-1,070 m). It is notably absent below the 100 foot elevation zone in the southern and eastern parts of its range .
Aspect influences the character of eastern redcedar stands. On north and east slopes, there may be fewer eastern redcedar trees because of hardwood competition. However, the eastern redcedar that does occur on north and east slopes may be taller than the trees found on south and west slopes . Eastern redcedar is generally more prevalent on south and south-west facing slopes . In the western part of its range, however, eastern redcedar may more likely be found on north-facing slopes and along streambanks where there is some protection from high temperatures and drought . On exposed areas in the far northern portion of its range, eastern redcedar's growth habit may be reduced to a low shrub .
Climate: Widespread distribution of eastern redcedar attests to its ability to grow under a range of climatic conditions. Precipitation averages 15 inches (380 mm) in the northwestern part of its range and 60 inches (1,520 mm) in the southeastern parts of its range [29,79,82,110]. Average annual maximum temperature ranges from 90 to 115 degrees Fahrenheit (32-46 oC) and average minimum temperature ranges from -45 to 20 degrees Fahrenheit (-43 to -7 oC). The growing season varies from about 120 to 250 days [79,82].
Soils and topography: Throughout its range, eastern redcedar grows under diverse site conditions: in deep and shallow soils, on ridgetops, and in valleys [46,47,64,79,114]. Eastern redcedar grows in such varied habitats as thin, rocky soils and dry outcrops to finer textured, saturated soils of swamps [18,63,64,79,82,110,132], though it is not tolerant of flooding . Eastern redcedar is common on shallow soils (6 to 8 inches (15-20 cm) thick) on limestone or sandstone bedrock [29,31,47,68]. Where soil averages less than 12 inches (30 cm) deep, eastern redcedar seldom grows taller than 20 to 30 feet (6-9 m). Where soil depth is 12 to 24 inches (30-60 cm), it reaches 35 feet (10.7 m) in approximately 50 years . Optimal site conditions for eastern redcedar are deep (>24 inches), moist, well-drained alluvial soils, where it may reach heights of 55 to 60 feet (16.7-18.3 m) after 50 years [46,79,82].
Eastern redcedar grows on alkaline or acidic soils where soil pH ranges from 4.7 to 7.8 [8,46,79,110]. High soil acidity does not deter eastern redcedar establishment [46,124], though it may slow growth . Combinations of low phosphorus, high calcium and pH>7 in particular may favor eastern redcedar . However, Lawson  reports that although eastern redcedar will grow on slightly alkaline soils, it is not particularly tolerant of higher pH levels. Eastern redcedar's occurrence on neutral to alkaline soils may be a result (rather than a cause) of the tree's presence . Soils in eastern redcedar stands tend to become neutral or slightly alkaline because the high calcium content of the tree's foliage can change the pH of the surface soil in a relatively short time [29,46,79].
Eastern redcedar (primarily J.v. var. virginiana) is commonly found on rough upland topography, including moderate to steep slopes and eroded limestone slopes and knobs [3,8,11,13,24,111,111,124]. It frequently forms dense stands on exposed bluffs and ridges . Southern redcedar occurs predominantly on coastal dunes, swales, shell mounds, brackish flats, and floodplains [3,36].
Tolerances: Southern redcedar is saline tolerant, growing on brackish marsh sites in southeastern U.S. , barrier island swales subject to saltwater flooding [122,136], and on coastal dunes subject to salt spray [64,69].
Eastern redcedar grows where water is near the surface or where soil moisture fluctuates from near saturation in winter to extreme dryness in summer . It has high drought tolerance [29,63,92,132], enhanced by the presence of rapidly produced taproots as well as an extensive fibrous root system . The relative drought tolerance of eastern redcedar compared with some herbaceous species (e.g. big bluestem) may contribute to its successful invasion of tallgrass prairie in the absence of fire .
Eastern redcedar is frost hardy [63,79,132], though newly established seedlings are subject to frost heaving and foliage may occasionally be damaged by winter injury .
Eastern redcedar is moderately shade intolerant/sun-adapted [18,79,92], though
seedlings may survive for several years under a sparse canopy [13,79,119,132].
Eastern redcedar is both a pioneer and an invader [13,30,134]. It colonizes relatively open patches of eroded bare ground and is most competitive on exposed dry sites; disturbed areas including abandoned pastures and cultivated fields, eroded areas, and open woods thinned by timber harvest [29,36,46,68,91,103,127,134,140]. Eastern redcedar does not establish well in more competitive, denser vegetation cover that occurs with less erosion or later in succession . However, in Texas savannas, eastern redcedar establishment may by facilitated by post oak trees, which are then overtopped and outcompeted by eastern redcedar .
Eastern redcedar a well-known invader in the prairie region [13,18,30,93]. Invasion into prairie grasslands is attributed primarily to absence of fire [9,22,93,117], and may be exacerbated by certain grazing practices [22,127]. A readily available seed source resulting from eastern redcedar plantings and ability to capitalize across a wide range of environmental conditions have also encouraged eastern redcedar establishment in grasslands . Eastern redcedar is thus an early to mid-seral component in cedar glades that result from the invasion of grasslands [11,18,58]. These glades eventually succeed to oak (Quercus spp.) -hardwood forests . Eastern redcedar glades may persist as subclimax vegetation where soil development is low and rock outcrops are abundant. The scarcity of soil precludes establishment of other species .
Eastern redcedar forms persistent, stable communities in limestone outcrop areas of the Interior Low Plateaus and the Limestone Valleys and Uplands Soils Province. These communities have been regarded as climax, subclimax, and edaphic climax. In particular, eastern redcedar stands may persist as subclimax forest on eroded limestone slopes and knobs . Persistent stands occurring on outcrops are subject to windthrow due to exposure and shallow soil. The result is a periodic opening of the stand favoring continued eastern redcedar establishment .
On the Atlantic coast, eastern redcedar may promote recruitment of mid-successional
woody seedlings (and impact their distribution) passively through distribution of
seeds by perching birds. Recruitment may be actively promoted
through increased seedling survival due to eastern redcedar alterations in
microclimate and edaphic factors. In a Virginia study, fleshy-fruited seeds of
woody species were more abundant in the seed bank beneath eastern redcedar than
in exposed sites. Photosynthetically active radiation was reduced under eastern
redcedar canopies, and soil temperature fluctuations were moderated during the
growing season. Moisture content, organic matter, and chlorides were higher for
soils under eastern redcedar than in exposed sites .
Eastern redcedar has small, inconspicuous flowers that appear from early to late spring [46,132]. Pollination occurs from February (south and east) to May (north and west), and fertilization occurs about a month later. Cones develop on male and female trees in the fall , and seeds mature in 1 season, from late July to mid-November depending on location [44,68,79,114,127,132]. As the ovulate cone develops, greenish fruit-scales form the outer fleshy protective coat of the berrylike cone. Cones change color from green to greenish-white to whitish-blue and finally to bluish as the season progresses. The cones do not open and will remain on the tree until early spring .
Fire regimes: Eastern redcedar frequently occurs on sites topographically and edaphically protected from fire, including bluffs, rocky hillsides, shale barrens of Virginia and West Virginia, limestone glades of Tennessee, Virginia, Missouri and Arkansas; serpentine barrens of Pennsylvania and Maryland; sandstone cliffs; granite outcrops; sand dunes; and estuarine swamps . Sites where eastern redcedar occurs as a persistent dominant are unlikely to support frequent fire due to rocky, shallow soils and low fuel loads . On shallow soils where litter accumulation is limited, the lack of fuel protects many eastern redcedar stands even where fire occurrence is high . However, in the absence of fire on adjoining uplands, eastern redcedar has been able to spread from these clifftop areas and invade uplands where it occupies a successional role . On deep soils, competing vegetation produces enough litter to support fire. Sufficient fuels to carry fire are usually available on grasslands and old agricultural fields, and a single fire may remove eastern redcedar from a site .
Fire suppression has resulted in the invasion of eastern redcedar into grasslands and savannas [58,131]. In areas that once burned periodically, eastern redcedar was protected from fire on dry or rocky sites lacking sufficient herbaceous fuel to carry fire. As fire frequency decreased, eastern redcedar invaded adjacent and apparently stable plant communities. Subsequently, individual eastern redcedars have increased in size and coverage, and stand density has increased. Large trees and dense stands shade or otherwise inhibit growth of desired herbaceous vegetation . In as little as 30 years after a fire, a treeless pasture can be converted to a closed canopy eastern redcedar forest [67,131].
A study of a cedar glade in southern Missouri found that fires occurred every 3.2 years during the presettlement period (1630-1870). After 1870, fire frequency decreased to 22 years . In a post oak savanna in southern Missouri, a study of fire scars on post oak, shortleaf pine, and eastern redcedar indicated a mean fire free interval of 4.3 years between 1700 and 1810. The period between 1785 and 1810 showed the most extensive evidence of fire, and fire frequency declined after 1860 (coincident with European settlement) .
Fire return intervals for plant communities and ecosystems where eastern redcedar is a common associate are summarized below. Find further 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)|
|sugar maple||Acer saccharum||> 1000|
|sugar maple-basswood||Acer saccharum-Tilia americana||> 1000 |
|bluestem prairie||Andropogon gerardii var. gerardii-Schizachyrium scoparium||< 10 [74,97]|
|Nebraska sandhills prairie||Andropogon gerardii var. paucipilus-Schizachyrium scoparium||< 10 |
|plains grasslands||Bouteloua spp.||< 35 [97,138]|
|blue grama-needle-and-thread grass-western wheatgrass||Bouteloua gracilis-Hesperostipa comata-Pascopyrum smithii||< 35 [97,107,138]|
|sugarberry-America elm-green ash||Celtis laevigata-Ulmus americana-Fraxinus pennsylvanica||< 35 to 200|
|Atlantic white-cedar||Chamaecyparis thyoides||35 to > 200|
|beech-sugar maple||Fagus spp.-Acer saccharum||> 1000 |
|juniper-oak savanna||Juniperus ashei-Quercus virginiana||< 35|
|Ashe juniper||Juniperus ashei||< 35|
|cedar glades||Juniperus virginiana||3-22 [58,97]|
|yellow-poplar||Liriodendron tulipifera||< 35 |
|wheatgrass plains grasslands||Pascopyrum smithii||< 5-47+ [97,100,138]|
|jack pine||Pinus banksiana||<35 to 200 |
|shortleaf pine||Pinus echinata||2-15|
|shortleaf pine-oak||Pinus echinata-Quercus spp.||< 10|
|slash pine||Pinus elliottii||3-8|
|slash pine-hardwood||Pinus elliottii-variable||< 35 |
|longleaf-slash pine||Pinus palustris-P. elliottii||1-4 [89,131]|
|longleaf pine-scrub oak||Pinus palustris-Quercus spp.||6-10 |
|red pine (Great Lakes region)||Pinus resinosa||10-200 (10**) [34,48]|
|red-white-jack pine*||Pinus resinosa-P. strobus-P. banksiana||10-300 [34,66]|
|eastern white pine||Pinus strobus||35-200|
|eastern white pine-eastern hemlock||Pinus strobus-Tsuga canadensis||35-200|
|eastern white pine-northern red oak-red maple||Pinus strobus-Quercus rubra-Acer rubrum||35-200|
|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|
|sycamore-sweetgum-American elm||Platanus occidentalis-Liquidambar styraciflua-Ulmus americana||< 35 to 200 |
|eastern cottonwood||Populus deltoides||< 35 to 200 |
|aspen-birch||Populus tremuloides-Betula papyrifera||35-200 [34,131]|
|black cherry-sugar maple||Prunus serotina-Acer saccharum||> 1000|
|oak-hickory||Quercus-Carya spp.||< 35|
|northeastern oak-pine||Quercus-Pinus spp.||10 to < 35|
|southeastern oak-pine||Quercus-Pinus spp.||< 10|
|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 |
|oak savanna||Quercus macrocarpa/Andropogon gerardii-Schizachyrium scoparium||2-14 [97,131]|
|shinnery||Quercus mohriana||< 35 |
|chestnut oak||Q. prinus||3-8|
|northern red oak||Quercus rubra||10 to < 35|
|post oak-blackjack oak||Quercus stellata-Q. marilandica||< 10|
|black oak||Quercus velutina||< 35|
|live oak||Quercus virginiana||10 to< 100 |
|little bluestem-grama prairie||Schizachyrium scoparium-Bouteloua spp.||< 35 |
|eastern hemlock-yellow birch||Tsuga canadensis-Betula alleghaniensis||> 200 |
|elm-ash-cottonwood||Ulmus-Fraxinus-Populus spp.||< 35 to 200 [34,131]|
|<3.3 feet (1 m)||88%|
|3.3 to 6.6 feet (1-2 m)||60%|
|6.6 to 9.9 feet (2-3 m)||35%|
|>9.9 feet (3 m)||10%|
In Leavenworth Barrens Nature Preserve, Indiana, low-severity spring prescribed
burns, exhibiting irregular burn patterns, were only effective in killing small
diameter eastern redcedar (1.5 inches (4 cm) basal diameter), while larger trees were
unaffected . A study of prescribed fire in a Missouri eastern redcedar glade
found that spring burning killed all trees up to 1.5 feet (0.5 m) tall but only
7% of the trees taller than 6.5 feet (2 m) .
PLANT RESPONSE TO FIRE:
Seedlings may be abundant following fire .
DISCUSSION AND QUALIFICATION OF PLANT RESPONSE:
No additional information is available on this topic.
FIRE MANAGEMENT CONSIDERATIONS:
In the absence of fire, eastern redcedar thrives and may eventually dominate prairie or forest vegetation [1,5,13,17]. Prescribed fire is generally effective at controlling eastern redcedar invasion in grasslands [13,77]. Spring burning is appropriate for eastern redcedar treatment because leaf water content is relatively low in late spring . Spring burns usually kill eastern redcedar up to 3.3 feet (1 m) tall [25,29,73,85], though larger trees up to 20 feet (6 m) are occasionally killed . In an Illinois barren community, eastern redcedar seedlings and saplings were eliminated for at least 20 years following a spring prescribed fire . In a Tennessee study over 20 years, eastern redcedar establishment was prevented using late winter prescribed surface fires annually and at 5-year intervals. On sites without fire treatment, eastern redcedar was recruited . On a Texas site, prescribed burning reduced eastern redcedar from an average preburn density of 19 stems/acre (0-49 stems/ha) to 0 stems/acre (measured 4 months after the burn), with the unburned control averaging 21 stems/acre (54 stems/ha) .
Though widely used, broadcast burning disadvantages include incomplete control, a narrow annual treatment window, and integrated prefire (to accumulate fine fuel) and postfire (to allow recovery of grasses) grazing management required to improve results . Degree of control depends on tree height, amount and distribution of herbaceous material that serves as fuel, backfire or headfire, and weather conditions favoring ignition of tree crowns .
Eastern redcedar trees <6 feet (1.8 m) tall are easily killed by prescribed burns with adequate grass fuel (~2,000 lbs/acre (2,268 kg/ha)) [17,39,77]. A Missouri study found that eastern redcedar mortality depended chiefly on the ratio of the amount of surface fuel to the amount of eastern redcedar foliage to be consumed (higher ratio = greater mortality). The ratio was affected both by size of the tree and density of the crown. Mortalities for eastern redcedar with very low, low, moderate, and high density crowns were 90%, 82%, 66%, and 35% respectively . Eastern redcedar is somewhat less susceptible to fire as tree size increases, so fire intensity must increase to scorch the crown of taller trees [37,85,94]. Larger trees may escape fire due to thicker bark, higher canopies , and a low fuel to foliage ratio . Headfires running with a 5- to 20-mph wind may be necessary to create flames that engulf the lower parts of large trees . Controlling trees >6 feet tall often requires more fuel than the range's potential production .
Fire intensity and tree mortality are reduced further in dense stands of large trees because junipers reduce production of fine fuels . The susceptibility of small eastern redcedar trees is enhanced because canopies of smaller trees do not have a large effect on surrounding herbaceous vegetation and stems are in close proximity to fine fuel . In a Missouri burn, large tree mortality depended on amount of herbaceous fuel and density of crowns. Trees having crowns with sparse foliage exhibited 90% mortality. Trees having larger crowns with dense foliage showed 35% mortality. Light crowned trees had more foliage beneath them than did densely crowned trees. Temperatures the day of the burn ranged from 28 to 60 degrees Fahrenheit (-2 to 15 oC), the lowest relative humidity was 26%, and winds averaged 4.7 mph [29,85].
Two prescribed fires conducted 1 week apart on tallgrass prairie in Missouri had varying results. The 1st fire occurred with higher humidity and wetter fuels, resulting in a less severe burn that allowed even eastern redcedar stems 0.6 inches (1.5 cm) in diameter to survive. Drier fuel conditions and lower humidity during the 2nd burn resulted in relatively greater fire severity that killed 93 to 100% of eastern redcedar up to 3.5 inches in diameter .
Because eastern redcedar growth rate and resistance to prescribed fire treatments increases at 15 to 20 years, control of invading trees is most effective at less than 10 years of age and 6.6 feet (2 m) tall . Eastern redcedar stands are often a mixture of tree sizes, and fuel loadings vary, so it is difficult to predict the extent of mortality following prescribed fire. In an Oklahoma study, eastern redcedar mortality for small (2 to 5 feet (0.6-1.5 m)), medium (5 to 8 feet (1.5-2.4 m)), and large (8 to 16 feet (2.4-4.9 m)) trees was 82, 54, and 39%, respectively. Fuel loads ranged from 1,300 to 6,100 lbs/acre (1,474-6,917 kg/ha), and tree mortality increased with increasing fuel load . Studies at Leavenworth Barrens Nature Preserve found spring prescribed burning was ineffective at controlling eastern redcedar greater than 1.6 inches (4 cm) in diameter; however, tree girdling in the fall followed by prescribed burning in the spring resulted in >50% immediate reduction of eastern redcedar with most of the remaining trees dying during the 1st growing season after treatment. Subsequent burning virtually removed eastern redcedar from the site . Use of defoliating herbicides prior to prescribed burning increases the leaf litter and may improve the effectiveness of fire treatments by increasing fire intensity [41,42]. Desiccation of eastern redcedar foliage increases crown scorch and mortality due to prescribed fire by promoting crown fire . Individual tree ignition following prescribed burning may be effective for removing any surviving eastern redcedar [40,93]. Picloram and/or cutting treatments may also be effective in removing larger eastern redcedar not killed by prescribed burning [93,94,117].
|Weather conditions for broadcast burns||Fine fuel loads by plot
Broadcast burning was followed by a variety of treatments to remove
individual eastern redcedars that survived the fire. These treatments included
burned/herbicide (picloram soil application), burned/mechanical removal,
burned/individual ignition, and burned/control (no follow-up). Unburned controls
were also subject to the follow-up treatments: unburned/herbicide,
unburned/mechanical, and unburned/control.
FIRE EFFECTS ON TARGET SPECIES:
Broadcast burn effects: Mean eastern redcedar mortality (%) by year and by height class, 3 weeks postfire, tended to be greater on west-facing than east-facing slopes:
|Aspect||Year||Height class (m)|
Mean eastern redcedar mortality increased from 77 to 92% 1 year after the 1993 burn and increased from 66 to 69% 1 year after the 1994 burn (based on burned/control treatments - see above). Delayed mortality may be the result of damage to the bark and cambium of eastern redcedar that is not immediately fatal. Foliage remaining on burned trees may be insufficient to support the root system, also contributing to delayed mortality.
Follow-up treatment effects: Mechanical treatments on both burned and unburned plots provided consistently high levels of control across all 4 height classes. Effectiveness of other follow-up treatments decreased with increasing height. Mean eastern redcedar mortality (%) 1 year after the burns and follow-up treatments is presented below:
|Treatment||Year||Height class (m)|
A fire-return interval for effective eastern redcedar control was estimated. Because broadcast burning can be expected to kill nearly 90% of trees <1 m tall and mortality diminishes with increasing height, the fire-return interval should be short enough to capture trees recruited since the last fire. Excessively short intervals, however, increase cost and management complications. This study suggests that 8 years may be the optimum fire return interval for eastern redcedar control in the Nebraska Loess Hills when follow-up treatments are used on trees >3 m tall that survive fire.
Palatability/nutritional value: Eastern redcedar fruits are high in crude fat and crude fiber, moderate in calcium, and high in total carbohydrates . Though considered poor quality forage , eastern redcedar foliage has relatively high calcium content, ranging from 1.9 to 2.6% on sites in the Ozarks .
Chemical analysis of eastern redcedar browse in the Missouri Ozarks (% dry matter) :
As an evergreen, eastern redcedar provides good nesting and roosting
cover for many birds [17,63,79]. These include nest sites for Cooper's hawks
 and roosting sites for eastern screech-owls [15,35], short-eared owls ,
and saw-whet owls . Dense thickets of eastern redcedar provide good
escape and hiding cover for deer and small mammals [17,63,79].
VALUE FOR REHABILITATION OF DISTURBED SITES:
Eastern redcedar establishes well on abandoned surface mines, agricultural fields, and logging sites [18,84] and is used to recover highly eroded, nutrient-poor soils . Use of eastern redcedar for rehabilitating strip-mines is most effective in calcareous spoils due to its slow growth on acid banks . Many cultivars of eastern redcedar are available, with variations primarily based on overall tree shape and the color of female cones . Greater planting success is likely with seed sources of geographic proximity . Planting recommendations include storing seed in fruit for 1 year, then cleaning, scarifying and sowing in the fall. Alternatively, seed can be stored in fruit for 1 year then cleaned and stratified in peat for 100 days at 41 degrees Fahrenheit (5 oC) and sown in the spring or stratified outdoors in the shade from May until sown in the fall .
Seeds of junipers (Juniperus spp.) have both seed coat and embryo dormancy . Maximum germination of eastern redcedar in minimum time may be achieved by treatment to increase seedcoat permeability and stratification . Eastern redcedar germination is improved by a combination of warm and cold stratification. Either 45 days of warm stratification followed by 60 days of cold stratification, or 60 days warm followed by 45 days of cold stratification yield best results. In lab tests, germination without stratification did not occur at temperatures above 59 degrees Fahrenheit (15 oC) . For storage, cleaned eastern redcedar seeds should be dried to 7% moisture content and stored at 20 degrees Fahrenheit (-7 oC) .
Commercial nurseries use propagation by rooted cuttings and grafting for
vegetative reproduction of eastern redcedar [79,127].
The aromatic oils found in eastern redcedar heartwood repel clothing moths and are widely used in perfumes [4,14,63,79,79]. Aromatic oils are toxic to some ant species (Argentine ant and odorous house ant), and eastern redcedar mulch is effective in discouraging ant colonization . Eastern redcedar oils are also effective in repelling Formosan subterranean termites . Heartwood extractives may inhibit growth of fungi and bacteria . Eastern redcedar heartwood has approximately 10 times the oil extractives of sapwood . Due to a higher proportion of heartwood to sapwood in closed-canopy stands of eastern redcedar, trees grown under closed stand conditions may contain 4 to 5 times as much oil in the bolewood as open-grown trees of the same diameter .
Eastern redcedar is commonly planted in shelterbelts, windbreaks, and snow fences [17,46,52,63,79,81,117]. It also used for Christmas trees [17,46,79] and ornamental plantings [52,63].
Eastern redcedar heartwood is resistant to attack by termites and has greater
commercial value than sapwood . The principal product of
eastern redcedar is fenceposts [8,110,117], though it is also used for lumber ,
poles, boats, paneling, closets, chests, and pencils [63,117].
The aromatic heartwood is commonly used for chests or closet lining [68,110].
On most sites, eastern redcedar grows slowly, and long rotations are
required to produce conventional sawlogs. However, because the wood is used for
small items and there is wide latitude in acceptable defects, shortening of
rotations and intermediate harvesting of merchantable wood are possible. About
20 to 30 years are required for posts and 40 to 60 years for sawtimber .
OTHER MANAGEMENT CONSIDERATIONS:
Thinning eastern redcedar windbreaks results in increased diameter and height growth of remaining trees, proportional to the amount of release . Thinning is also useful in maintaining eastern redcedar glades where the hardwood understory is not well established. Harvest opens the stand and exposes seedlings to higher light intensity and potentially eliminates the shade-tolerant successional species. However, where successional species are well established, thinning may hasten succession .
Eastern redcedar severely limits forage beneath its canopy but has little effect on forage production outside the canopy [17,38]. At high tree densities, canopy closure is rapid and results in low plant diversity [17,51,72]. The Flint Hills area in eastern Kansas consists of tallgrass prairie invaded by eastern redcedar. One study found a significant negative relationship between species richness and tree density (p<0.0001), as well as significantly fewer herbaceous species (p<0.0001) under the eastern redcedar canopy than outside the canopy. Eastern redcedar forests had a 99% decrease in herbaceous production compared to the tallgrass prairie . In Nebraska, many plant community dominants of the bluestem prairie are reduced under eastern redcedar cover . At 2 tallgrass prairie sites in Nebraska, studies estimated that herbaceous biomass production under eastern redcedar canopies averaged 83% less than in the interstitial spaces, possibly due to an 85% reduction in light and 11.5% reduction in soil moisture . In tallgrass prairies, it is realistic to expect yields of 4,000 pounds forage per acre per year. With 200 eastern redcedar seedlings per acre (500 seedlings/ha), yield will decrease to 2,200 pounds per acre per year. Five hundred seedlings per acre (1,250 seedlings/ha) reduce annual forage production to 600 pounds per acre . Analysis of aerial photos from the Flint Hills of eastern Kansas indicated that eastern redcedar can expand and convert tallgrass prairie to a closed-canopy forest in as little as 40 years . Loss of forage may contribute to soil erosion and decreased water infiltration .
Eastern redcedar may produce allelochemicals that affect establishment of at least some prairie species. In a Nebraska study, establishment of finger coreopsis (Coreopsis palmata) from seed collected beneath eastern redcedar trees was significantly lower (95% confidence interval) than establishment from seed collected adjacent to the trees (84% germination v. 0%) .
Mechanical treatments that sever or dig up eastern redcedar provide effective control due to eastern redcedar's inability to sprout [17,93].
Eastern redcedar is resistant to most foliar herbicides, though soil-applied herbicides may provide effective control on small acreages [17,112]. Eastern redcedar is relatively insensitive to foliar application of 2,4,5-T and 2,4-D [25,46]. Indiscriminate spraying of these herbicides to reduce woody species and convert areas to grassland may eliminate hardwood associates from stands while releasing eastern redcedar and promoting eastern redcedar's dominance . In studies at Leavenworth Barrens Nature Preserve, Indiana, eastern redcedar survived girdling combined with glyphosate application . In an Oklahoma study, paraquat foliar herbicide killed up to 90% of the crown of small trees (2.5 to 5 feet (0.8-1.5 m) tall) but as little as 30% of the crown of large trees (8-16 feet (2.5-5.0 m) tall) . Other studies have found that foliar-stem treatments with picloram alone or in combination with 2,4,5-T or 2,4-D were effective in controlling eastern redcedar [25,95]. Soil applied herbicides, particularly picloram, may be more effective for eastern redcedar control . In 1 study, soil spot applications of undiluted picloram achieved 48 to 100% mortality of eastern redcedar by 18 months posttreatment. However, the use of liquid picloram may be ineffective where trees are taller than 15 feet (5 m) or where excessive litter could prevent root zone penetration of the chemical . A Nebraska study demonstrated variable control of eastern redcedar using soil applications of hexazinone (68-90% mortality), picloram (70-94% mortality), and tebuthiuron (71-90% mortality), based on application rate and tree height . Soil-applied herbicides may be more effective when used as follow-up treatments to broadcast burning .
Eastern redcedar is particularly suited to conditions coincident with heavy grazing . Grazing of the tallgrass prairie into late summer or early fall leaves little standing vegetation to support fires with sufficient intensity to kill eastern redcedar the following spring. This management practice promotes the continued establishment and growth of eastern redcedar in the grasslands, even in areas that are frequently burned [22,23]. However, eastern redcedar roots are damaged by the hooves of grazing animals and browsing may severely limit seedling and sapling height growth [46,132]. Some authors note that increased stocking rates of cattle may decrease eastern redcedar invasion. Mice, rabbits, and deer may also damage seedlings [29,79].
Several insects damage eastern redcedar but rarely cause serious permanent damage. Roots of seedlings are very susceptible to attack by nematodes and grubs. Bagworms and spruce spider mites can completely defoliate eastern redcedar, and it is susceptible to some bark beetles and several boring insects and root weevils. Eastern redcedar, especially when weakened by stress or insects, is very susceptible to damage by root rot fungi as well as cedar rust fungi that attack the stem and foliage . The most commonly known and widely spread species for which eastern redcedar is an alternate host is cedar-apple rust, which produces conspicuous gall-like growths on the plant and is a serious pathogen of cultivated apples [65,79,110,117,124,127]. Specific insect pests and diseases are identified by Lawson .
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