FIRE EFFECTS
SPECIES: Juniperus ashei | Ashe Juniper 



IMMEDIATE FIRE EFFECT ON PLANT : 
Ashe juniper seedlings are easily killed by low-severity fires.  Hot
fires can kill large Ashe juniper trees [50,56].  Scorching 60 percent
of the crown will kill most Ashe juniper trees [44].


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
Colonization of burned areas occurs through seed dispersed by birds or
mammals, or by seed that survived fire.  It can take 10 to 40 years for
Ashe juniper to establish stands that are over 4 feet (1.2 m) tall [33,50].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
Dead Ashe 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 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 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 Oaklahoma.  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 dessicant to
promote crown fires in closed-canopy stands of Ashe 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 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 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 juniper; a general rule of thumb is to burn
when Ashe juniper trees are 4 feet (1.2 m) tall [33,34,38,53].

Related categories for Species: Juniperus ashei | Ashe Juniper