Ashe Juniper

The name Juniperus mexicana Sprengel has been misapplied to this species. Reports of hybridization with J . virginiana and J . pinchotii have been refuted using numerous chemical and morphologic characters (R. P. Adams 1977).

Ashe juniper is a source of Texas-cedarwood oil and fence posts.

Trees dioecious, to 15 m, single-stemmed to 1--3 m, occasionally branching at base; crown rounded to irregular and open. Bark brown, exfoliating in thin strips, that of small branchlets (5--10 mm diam.) smooth, that of larger branchlets exfoliating in strips. Branches spreading to ascending; branchlets erect, 3--4-sided in cross section, ca. 2/3 or less as wide as length of scalelike leaves. Leaves dark green, abaxial glands hemispheric, raised (particularly obvious on whip leaves), exudate absent, margins denticulate (at 20´); whip leaves 3--6 mm, not glaucous adaxially; scalelike leaves 1--2 mm, not overlapping or overlapping to 1/4 their length, keeled, apex acute to obtuse, spreading. Seed cones maturing in 1 year, of 1 size, with straight peduncles, ovoid to nearly globose, 6--9 mm, dark blue, glaucous, fleshy and resinous, with 1(--3) seeds. Seeds 4--6 mm. 2 n = 22.

Ark., Mo., Okla., Tex.; Mexico.

Limestone glades and bluffs; 150--600m.

More info for the terms: shrub, tree

Ashe's juniper
mountain cedar
rock cedar
Ozark white cedar
post cedar
Mexican juniper
break cedar
brake cedar
Texas cedar
sabino
enebro
cedro
tascate
Texate


TAXONOMY:
The scientific name for Ashe's juniper is Juniperus ashei Buchholz.
(Cupressaceae). Ashe's juniper is thought to hybridize with Pinchot's
juniper (J. pinchotii) [19,30]. Adams and Kistler [3] summarized a number
of studies that investigated the report that Ashe's juniper hybridizes with
eastern redcedar (J. virginiana) [17,18]. They concluded that there was
no evidence of gene flow between the two species, even though their
ranges overlap and morphological intermediates exist. There are no
recognized subspecies, forms, or varieties of Ashe's juniper.


LIFE FORM:
Tree, Shrub

FEDERAL LEGAL STATUS:
No special status

OTHER STATUS:
NO-ENTRY




DISTRIBUTION AND OCCURRENCE
SPECIES: Juniperus ashei
GENERAL DISTRIBUTION:
Ashe's juniper has a limited range in southwestern North America.  It
occurs in disjunct populations in southwestern Missouri and Arkansas, in
the Arbuckle Mountains of southern Oklahoma, and in Coahuila, Mexico.
The main population occurs in west-central Texas, largely on the Edwards
Plateau [20,28,41].

More info for the term: forest

Ashe's juniper has a limited range in southwestern North America.  It
occurs in disjunct populations in southwestern Missouri and Arkansas, in
the Arbuckle Mountains of southern Oklahoma, and in Coahuila, Mexico.
The main population occurs in west-central Texas, largely on the Edwards
Plateau [20,28,41].



Distribution of Ashe's juniper. 1971 USDA, Forest Service map digitized by Thompson and others [59].

More info for the terms: cover, fire management, forest, fuel, headfire, herbaceous, natural, prescribed fire, tree

Dead Ashe's juniper trees are highly volatile fuels and must be treated
with caution.  Firebrands can carry up to 400 feet (120 m), depending on
conditions, and can ignite spot fires, especially where there is a
preponderance of highly flammable dried animal dung.

Prescribed burning is rarely used alone on mature Ashe's juniper stands,
as there is usually not enough fine fuel to carry fire [34,52].  Wright
and Bailey [53], however, list it as a technique to convert dense stands
into more open stands.

Chained stands are the easiest to burn; herbicide-treated or treedozed
stands can also be successfully burned [34,52,53].  In order to carry
fire to ignite piles and burn seedlings, it is generally recommended
that there be a minimum of 1,000 pounds per acre (1,120 kg/ha) of fine
fuels, and 2,000 pounds per acre (2,240 kg/ha) of continuous fine fuel
is optimal [34,50,52,53].  The lower figure is not sufficient if it
consists of bunchgrasses.  Plots consisting of dozed or chained Ashe
juniper piles interspersed with grasses and Ashe's juniper seedlings may
be safely burned with a headfire into a 500 foot (150 m) fireline under
certain conditions [9,34,52,53].

Dalrymple [11] reported 100 percent mortality of individuals less than 2
feet (0.6 m) and 77 percent mortality of trees from 2 to 6 feet (0.6-1.8
m) tall after a prescribed fire in Okalahoma.  Less than 25 percent of
trees taller than 6 feet (1.8 m) were killed.  Juniper (Juniperus spp.)
trees in open stands can be individually ignited and burned using
propane or oil burners [44].

Some authors recommend windrowing of larger trees rather than dozing for
achieving crown fires.  With windrows, six trees are burned for every
tree pushed into standing tree lines [6,8].  Good tree to tree spread of
fire does not occur unless the trees are less than 26 feet (8 m) apart
[6].  Since leaf moisture is one of the most important variables for
satisfactory burning, Engle and Stritzke [12] tested the proposition
that an aerial application of paraquat could reduce foliage water
content and increase crown scorch during broadcast fires in tallgrass
prairie.  They found that the leaf water content was significantly lower
(p < 0.0001) for all applied levels of paraquat, and that large trees
were more damaged by the paraquat plus fire treatment than by fire alone
(p < 0.0319).  They conclude that paraquat can be used as a desiccant to
promote crown fires in closed-canopy stands of Ashe's juniper.

One of the major environmental concerns about the use of prescribed fire
for rangeland management is increased soil loss caused by the removal of
vegetation.  Wright and others [54] tested the effect prescribed burning
of Ashe's juniper had on erosion and found that for very gentle slopes (1
to 4 percent grade), there was very little soil loss, but on moderate
(15 to 29 percent) or steep (45 to 53 percent) slopes the losses
increased greatly.  The amount and duration of soil loss depended
largely on vegetative cover and slope.  The negative effects of burning
Ashe's juniper can be mitigated by artificially seeding moderate and steep
slopes. With adequate precipitation, the resulting ground cover can
reduce the amount of time needed to stabilize soils from 18 months to 3
months on steep slopes.  Total stabilization (i.e.  return to
pretreatment levels of soil loss) can be reduced from 42 months to 6
months, again with adequate precipitation [54].

A 10- to 40-year interval between prescribed fires is recommended to
maintain control of Ashe's juniper; a general rule of thumb is to burn
when Ashe's juniper trees are 4 feet (1.2 m) tall [33,34,38,53].


FIRE CASE STUDY
SPECIES: Juniperus ashei
FIRE CASE STUDY CITATION:
Sullivan, Janet., compiler. 1993. Effects of fire on Ashe's juniper in central Texas.
In: Juniperus ashei. 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/ [
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REFERENCE:
Wink, Robert L.; Wright, Henry  A. 1973. Effects of fire on an ashe
juniper community. Journal of Range Management. 26(5): 326-329. [50].

SEASON/SEVERITY CLASSIFICATION:
1) Spring/low--followed wet winter and spring
2) Spring/high--followed dry winter and spring


STUDY LOCATION:
The Beckham Ranch, Callahan County, 14 miles (24 km) southeast of Baird,
Texas.


PREFIRE VEGETATIVE COMMUNITY:
The natural vegetation of the area consists of mixed-prairie grasses
interspersed with Ashe's juniper and several species of oak.  The dominant
decreasers are little bluestem (Schizachyrium scoparium) and sideoats
grama (Bouteloua curtipendula).  Important increasers are buffalograss
(Buchloe dactyloides), vine-mesquite (Panicum obtusum), Texas
wintergrass (Stipa leucotricha), tall grama (B. pectinata) and meadow
dropseed (Sporobolus asper var. hookeri).


TARGET SPECIES PHENOLOGICAL STATE:
Large Ashe's juniper trees were bulldozed and piled in 1965 (burning took
place in 1970 and 1971).  Small Ashe's junipers that escaped the
bulldozers and new seedlings were also present.


SITE DESCRIPTION:
Average annual precipitation is 24 to 28 inches (600-700 mm).  The
topography of the area is level to undulating with some slopes greater
than 20 percent.  Elevation is 1,198 to 1,394 feet (365-425 m).  The
average minimum January temperature is 23 degrees Fahrenheit (-5 deg C),
and the average maximum July temperature is 95 degrees Fahrenheit (35
deg C).  The average growing season is 232 days.

Sandy loam sites in the study area have deep soils with fine sandy loam
surfaces 6 to 14 inches (15-36 cm) thick, and sandy clays and sandy loam
subsoils.  The soils are slowly to moderately permeable.  The low stony
hill site consists of very shallow, moderately permeable, calcareous,
stony clay soils.  Depth ranges from 6 to 12 inches (15-31 cm) with
limestone rocks and boulders present on the surface and in the profile
in various amounts.

All three sites were sampled for herbage production and fine fuel
concentration, and individual plots were marked to measure pile
consumption and tree mortality.  The uniformly fine fuels ranged from
686 to 3,186 pounds per acre (768-3,568 kg/ha).  The estimated amount of
heavy fuels (piles of Ashe's juniper) varied from 20 to 30 tons per acre
(44.8-67.2 t/ha) and occupied from 0 to 85 percent of the area with
an average cover of 22 percent.


FIRE DESCRIPTION:
Air temperature:  75 to 86 degrees Fahrenheit (24-30 deg C)
humidity: 25-35 percent
wind speed: 10 to 15 miles per hour (16-25 km/h)

The objectives of the prescribed fires were to consume the piles of dead
trees and to burn the intervening areas where Ashe's juniper seedlings had
established.  Fires were conducted in 2 separate years.  In March of
1970, one pasture of 1,013 acres (405 ha) was burned, and in March 1971,
2 pastures for a total of 1,620 acres (648 ha) were burned.  All areas
were burned with headfires.  The ignition pattern was a combination of
perimeter and strip headfiring.

Fire intensities were not reported.


FIRE EFFECTS ON TARGET SPECIES:
Plots on which fine fuels were 686 and 859 pounds per acre (768 and 962
kg/ha) were not successful in carrying the fire.  On plots where fine
fuels exceeded 1,000 pounds per acre (1,120 kg/ha), 99 percent of the
piles were consumed by fire.  The March 1971 fires followed 6 months of
very dry weather and were conducted under the lowest humidities and
highest winds that could be tolerated for prescribed burning.  Where
large piles were within 40 feet (12 m) of each other, firebrands would
ignite the piles downwind, precluding the necessity of continuous fine
fuel.

Ashe's juniper mortality was high where the fine fuels were adequate to
carry the headfire.  Of 368 trees under 6 feet (1.8 m) tall, only one
survived.  Many trees over 6 feet (1.8 m) tall were killed by the fire,
particularly where fine fuels exceeded 2,000 pounds per acre (2,240
kg/ha).


FIRE MANAGEMENT IMPLICATIONS:
Prescribed burning is a useful method for controlling Ashe's juniper
encroachment on grasslands.  It is recommended that the larger trees be
chained or dozed to assure mortality and to concentrate dead stems into
piles.  Fires require a minimum of 1,000 pounds per acre (1,120 kg/ha)
of fine fuels for successful spread, and 2,000 pounds per acre (2,240
kg/ha) is optimal.  Soil moisture should be a primary consideration
before conducting a prescribed fire.  Herbaceous plants require good
soil moisture for rapid recovery after the fire, which helps reduce soil
erosion.  Burning increased the yield of little bluestem and meadow
dropseed after the 1970 fire, which followed a wet winter and spring.
The same species decreased about 50 percent after the 1971 fires
following a dry winter and spring.

Vegetation on the burned juniper pile areas differed from that adjacent
to the piles.  Silver leaf nightshade (Solanum elaeagnifolium) and
Carolina horsenettle (S. carolinense) were dominant on the burned pile
areas, and may need to be controlled with herbicides.  Smoothleaf sumac
(Rhus glabra) also increase in prominence on the burned pile areas.

More info for the terms: herbaceous, prescribed fire

Prescribed burning is a useful method for controlling Ashe's juniper
encroachment on grasslands.  It is recommended that the larger trees be
chained or dozed to assure mortality and to concentrate dead stems into
piles.  Fires require a minimum of 1,000 pounds per acre (1,120 kg/ha)
of fine fuels for successful spread, and 2,000 pounds per acre (2,240
kg/ha) is optimal.  Soil moisture should be a primary consideration
before conducting a prescribed fire.  Herbaceous plants require good
soil moisture for rapid recovery after the fire, which helps reduce soil
erosion.  Burning increased the yield of little bluestem and meadow
dropseed after the 1970 fire, which followed a wet winter and spring.
The same species decreased about 50 percent after the 1971 fires
following a dry winter and spring.

Vegetation on the burned juniper pile areas differed from that adjacent
to the piles.  Silver leaf nightshade (Solanum elaeagnifolium) and
Carolina horsenettle (S. carolinense) were dominant on the burned pile
areas, and may need to be controlled with herbicides.  Smoothleaf sumac
(Rhus glabra) also increase in prominence on the burned pile areas.

More info for the terms: codominant, fire suppression

Ashe's juniper forms dense to open communities with oaks (Quercus spp.),
including live oak (Q. virginiana) and Mohr oak (Q. mohriana), Texas
persimmon (Diospyros texana), and mesquite (Prosopis spp.).  These
communities have invaded many acres of adjacent little bluestem
(Schizachyrium scoparium) grasslands as a result of overgrazing and fire
suppression [42].

Publications which list Ashe's juniper as a dominant or codominant
species include:

Utilization of grass- and shrublands of the southwestern United States [21]. 
A comparison of some woody upland and riparian plant communities
  of the southern Edwards Plateau [46].
An ecological comparison of upland deciduous and evergreen forests of
  central Texas [45]. 
North American shrublands [31].

More info for the terms: shrub, tree

Tree, Shrub

More info for the terms: cover, grassland, litter, seed, stratification

In the last century on the Edwards Plateau in Texas, scrub oak (Texas
live oak [Quercus virginiana var. fusiformis] and Vasey oak [Q. pungens
var. vaseyana])-juniper communities have spread onto the mixed prairie.
This vegetative shift is due largely to the absence of fire, but
overgrazing, seed dispersal by livestock, and a possible shift in
climate are contributing factors [38,39,42].  It is currently estimated
that Ashe's juniper occupies 0.5 million acres in southern Oklahoma and
8.6 million acres in Texas, much of it on former grasslands [16].  Large
dense stands of Ashe's juniper are considered detrimental to both
livestock and wildlife; white-tailed deer prefer open stands and edges
close to cover and a variety of foods.  Dense stands of Ashe's juniper
reduce the amount of understory vegetation, resulting in a decrease in
available forage [33].

Chemical control:  Grumbles [16] reported that spot-application of
picloram at a rate of 0.1 ounce active ingredient (4 mL) per 3 feet (90
cm) of crown canopy diameter resulted in 97 percent mortality, except
for the very largest trees (over 15 feet [4.5 m] crown diameter).
Failure to kill the largest trees was attributed to heavy litter layers
and low precipitation.  The study also determined that spring
applications were more effective than fall applications.  Other authors
do not believe that herbicides are effective or economical in
controlling Ashe's juniper, and that use of herbicides can be detrimental
to other species [40,49].

Mechanical control:  Thirteen to eighteen years after Ashe's juniper was
removed by treedozing only (no burning of piles or downed trees), Ashe
juniper comprised 50 percent or more of the total brush cover.  Such
treatment leaves the seedbank intact, allowing Ashe's juniper to
reestablish fairly rapidly.  In similar areas where Ashe's juniper was
removed by treedozing and the piles burned 5 years later, Ashe's juniper
comprised less than 14 percent of total brush cover [35].  Double
chaining Ashe's juniper into piles and then burning the piles the same
year reduced Ashe's juniper cover by 93 percent [38].  Ashe's juniper trees
less than 5 feet (1.5 m) tall are not pulled up by chaining, so the
areas need to be broadcast burned to kill the young Ashe's junipers
between piles.  Single chaining is probably effective on pure, even-aged
Ashe's juniper stands and is less expensive than double chaining.  The
double chaining method is recommended for stands which are uneven-aged
or have other species present in substantial numbers [38].  To summarize
the recommended treatments:  Ashe's juniper should be reduced by
mechanical means and then burned about 5 years later.  Any undesirable
species can be spot treated with herbicides; the area should be burned
again when Ashe's juniper saplings reach 4 feet (1.2 m) in height
[33,34,35,52,53].

Sprouting species, such as Mohr oak and flameleaf sumac (Rhus
copallina), may increase on rangeland where Ashe's juniper is controlled
by burning.  The particular species depends on prior establishment,
treatment, and factors related to soil and aspect.  Brush species have
to be evaluated as to their contribution to management goals.  It is
often the case that the sprouting species are palatable and nutritious
for livestock and wildlife, and can be controlled by grazing practices.
Other species not removed by fire may not be desirable for livestock or
wildlife, and need to be controlled by other means (usually herbicides)
[33,35].

In general, it is neither possible nor desirable to eradicate all trees
and brush from the rangelands on the Edwards Plateau.  Current
management on public lands and on private ranches recognizes the
economic value of white-tailed deer.  A mixed pattern of open stands and
grassland is more desirable for deer and is also acceptable for
livestock [7,38,39].

Culture:  Germination of Ashe's juniper seeds is enhanced by cold
stratification at 41 degrees Fahrenheit (4 deg C) for 120 days.  Ashe
juniper seeds should be sown in the fall or cold stratified and sown in
the spring.  They can be drill seeded or hand broadcast and should be
mulched.  Seedlings need light shade the first growing season, as they
are easily damaged by excessive heat.  Junipers in general are resistant
to damping off and root rot [23].

Diseases:  Ashe's juniper is susceptible to juniper blight (Phomopsis
juniperova), which infects foliage and stem tissue.  This is a
particular problem in nursery stock.  Total loss of seedlings can occur
in epidemic years.  Older trees are seldom killed; mortality occurs
through girdling of small diameter stems.  Control consists of the
fungicide, Benomyl, applied throughout the growing season.  Ashe's juniper
is resistant to cedar-apple rust (Gymnosporangium juniperi-virginianae)
[23,37,47].

More info on this topic.

More info for the term: fruit

The staminate catkins of Ashe's juniper open in early spring [23].
Pollination of the ovulate cones occurs at this time; the fruit develops
through its first summer and is ripe in early fall and winter.  The
"berries" usually persist through the winter [47].  Germination is in
the spring, usually after one, two, or three winters [23].

More info for the terms: root crown, secondary colonizer, tree

   Tree without adventitious-bud root crown
   Secondary colonizer - off-site seed

1) Spring/low--followed wet winter and spring
2) Spring/high--followed dry winter and spring

More info for the terms: cover, fuel, tree

Average annual precipitation is 24 to 28 inches (600-700 mm).  The
topography of the area is level to undulating with some slopes greater
than 20 percent.  Elevation is 1,198 to 1,394 feet (365-425 m).  The
average minimum January temperature is 23 degrees Fahrenheit (-5 deg C),
and the average maximum July temperature is 95 degrees Fahrenheit (35
deg C).  The average growing season is 232 days.

Sandy loam sites in the study area have deep soils with fine sandy loam
surfaces 6 to 14 inches (15-36 cm) thick, and sandy clays and sandy loam
subsoils.  The soils are slowly to moderately permeable.  The low stony
hill site consists of very shallow, moderately permeable, calcareous,
stony clay soils.  Depth ranges from 6 to 12 inches (15-31 cm) with
limestone rocks and boulders present on the surface and in the profile
in various amounts.

All three sites were sampled for herbage production and fine fuel
concentration, and individual plots were marked to measure pile
consumption and tree mortality.  The uniformly fine fuels ranged from
686 to 3,186 pounds per acre (768-3,568 kg/ha).  The estimated amount of
heavy fuels (piles of Ashe's juniper) varied from 20 to 30 tons per acre
(44.8-67.2 t/ha) and occupied from 0 to 85 percent of the area with
an average cover of 22 percent.

The scientific name for Ashe's juniper is Juniperus ashei Buchholz.
(Cupressaceae). Ashe's juniper is thought to hybridize with Pinchot's
juniper (J. pinchotii) [19,30]. Adams and Kistler [3] summarized a number
of studies that investigated the report that Ashe's juniper hybridizes with
eastern redcedar (J. virginiana) [17,18]. They concluded that there was
no evidence of gene flow between the two species, even though their
ranges overlap and morphological intermediates exist. There are no
recognized subspecies, forms, or varieties of Ashe's juniper.

Tree, Evergreen, Dioecious, Habit erect, Trees without or rarely having knees, Tree with bark shaggy or peeling, Young shoots in flat sprays, Young shoots 3-dimensional, Buds not resinous, Leaves scale-like, Whip leaves present, Leaves of two kinds, Leaves opposite, Leaves whorled, Non-needle-like leaf margins entire, Leaf apex acute, Leaf apex obtuse, Leaves < 5 cm long, Leaves < 10 cm long, Leaves not blue-green, Scale leaves with raised glands, Scale leaf glands not ruptured, Scales leaves not or barely overlapping, Whip leaf margins entire under magnification, Twigs glabrous, Twigs not viscid, Twigs without peg-like projections or large fascicles after needles fall, Aril completely enclosing seed coat, Berry-like cones pink, Bracts of seed cone included, Seeds tan, Seeds brown, Seeds wingless.

Juniperus ashei (Ashe juniper, mountain cedar, blueberry juniper, post cedar, or just cedar) is a drought-tolerant evergreen tree, native from northeastern Mexico and the south-central United States to southern Missouri. The largest areas are in central Texas, where extensive stands occur. Ashe juniper grows up to 10 metres (33 feet) tall, and over time can reach 15 m (49 ft), and provides erosion control and year-round shade for wildlife and livestock.