1Up Info - A Portal with a Difference

1Up Travel - A Travel Portal with a Difference.    
1Up Info
   

Earth & EnvironmentHistoryLiterature & ArtsHealth & MedicinePeoplePlacesPlants & Animals  • Philosophy & Religion  • Science & TechnologySocial Science & LawSports & Everyday Life Wildlife, Animals, & PlantsCountry Study Encyclopedia A -Z
North America Gazetteer


You are here >1Up Info > Wildlife, Animals, and Plants > Plant Species > Tree > SPECIES: Pseudotsuga menziesii var. glauca | Rocky Mountain Douglas-Fir
 

Wildlife, Animals, and Plants

 


Wildlife, Animals, and Plants

 

Wildlife Species

  Amphibians

  Birds

  Mammals

  Reptiles

 

Kuchler

 

Plants

  Bryophyte

  Cactus

  Fern or Fern Ally

  Forb

  Graminoid

  Lichen

  Shrub

  Tree

  Vine


FIRE CASE STUDIES

SPECIES: Pseudotsuga menziesii var. glauca | Rocky Mountain Douglas-Fir
  • 1st CASE STUDY:
  • Lubrecht Experimental Forest: prescribed fire in a western larch/Rocky Mountain Douglas-fir stand
  • 2nd CASE STUDY:
  • Miller Creek-Newman Ridge: Prescribed fire and wildfire in a western larch/Rocky Mountain Douglas-fir stand

1st CASE STUDY: CASE NAME:
Lubrecht Experimental Forest: prescribed fire in a western larch/Rocky Mountain Douglas-fir stand

REFERENCES:
Norum, R. A. 1975 [190]
Norum, R. A. 1976 [191]
Norum, R. A. 1977 [192]
Reinhardt, E. D.; Ryan, K. C. 1988 [213]
Ryan, K. C.; Peterson, D. L.; Reinhardt, E. D. 1988 [225]
Stark, N. 1977 [245]
Stark, N.; Steele, R. 1977 [244]

FIRE CASE STUDY AUTHORSHIP:
Crane, Marti. April 1991.

SEASON/SEVERITY CLASSIFICATION:
Spring and fall/low to moderately-severe

STUDY LOCATION:
The study site is the University of Montana Lubrecht Experimental forest located 41 miles (66 km) east of Missoula, Montana in the Garnet Mountains (north half of Section 3, T. 13 N, R. 15 W, Principal Meridian, Montana).

PREFIRE VEGETATIVE COMMUNITY:
Study plots were in a Rocky Mountain Douglas-fir (Pseudotsuga menziesii var. glauca)/big huckleberry (Vaccinium membranaceum) habitat type, kinnikinnick (Arctostaphylos uva-ursi) phase as described by Pfister and others [205]. Overstory trees ranged in age from 50 to 300 years; average diameter was 8.6 inches (22 cm). This stand was not vigorous and was composed primarily of Rocky Mountain Douglas-fir and western larch (Larix occidentalis) with small amounts of Rocky Mountain lodgepole pine (Pinus contorta var. latifolia) and Pacific ponderosa pine (P. ponderosa var. ponderosa). The largest, high-quality trees had been selectively logged about 50 years prior to the study. Subsequently an uneven understory of dense Rocky Mountain Douglas-fir had developed. There were a large number of widely spaced, large diameter western larch stumps indicating preharvest structure. In addition to conifers and kinnikinnick, huckleberries (Vaccinium spp.), white spirea (Spiraea betulifolia), and heartleaf arnica (Arnica cordifolia) were common in the understory [190,225].

TARGET SPECIES PHENOLOGICAL STATE:
About half of the fires occurred between May and early June after bud burst and shoot elongation initiation; the rest occurred in September and October when growth rates were probably very low and cones had already opened.

SITE DESCRIPTION:
The site is located at about 4,800 feet (1,464 m) with east to northeast exposures and slopes of 15 to 45% [213,225]. The area has warm summers and cold winters with annual precipitation of about 18 inches (470 mm), most of which falls as winter snow. Soils in the area are thin, poorly developed, sandy loams in the Holloway Series. They formed in residuum weathered from quartzite, argillite and, on these sites, contain sufficient rock to be considered talus slopes. Calcium and phosphate are limited in these soils. The site had a substantial complex fuel load including many dead small trees in understory thickets. Total dead fuel loadings ranged from 5.5 to 50 tons per acre (12.3-112.1 t/ha) [225]. 

FIRE DESCRIPTION:
Nine plots were burned in May to early July, and 11 were burned during September to mid-October with the objectives of developing techniques for controlled burning to reduce fuel accumulation and stand density [213,225]. Out of the 20 test plots broadcast burned during 1973, 9 were burned from early May to the 1st of July. The rest were burned from early September to mid-October. The average dead fuel moisture contents ranged from 8.5 to 35% and wind speeds were from 0 to 15 miles per hour (0-24 km/hr). Most plots were ignited in strips. Fire intensity on each strip was allowed to drop before the next strip was ignited. Maximum fire intensities ranged from 100 kW/m2 to 900 100 kW/m2. The herbaceous moisture content, weight of woody shrubs, weight of herbaceous material and duff moisture were variable across the landscape and were important factors in fire behavior in these stands [225]. Over 100 fire parameters were measured. 

FIRE EFFECTS ON TARGET SPECIES:
Diameter, height, average height of needle scorch, and percentage of the prefire crown volume scorched were measured on 166 burned Rocky Mountain Douglas-fir trees a few weeks after the fires. Four cambium samples per tree were taken at breast height in the spring of 1974 and tested for living tissue. In 1981 the trees were revisited, and 83 (50%) were dead. Fifty-three percent of the dead trees had been burned in spring fires and the other 47% in fall fires. Approximately 22% of the trees appeared to have died in 1974, 20% in 1975, and the other 8% during the next 6 years. Seven percent of the dead trees had no measured crown or bole damage. Mean measurements of the affected trees are organized by their 1981 status and the fire season in which they were burned and are presented below [225]:

 

Dead

Alive

Spring  Fall Spring  Fall
Diameter (inches (cm)) 6.9 (17.4) 7.3 (18.5) 8.9 (22.6) 9.5 (24.0)
Tree height (feet (m)) 42.3 (12.9) 45.9 (14.0) 51.8 (15.8) 49.8 (15.2)
Scorch height (feet (m)) 25.0 (7.6) 24.2 (7.4) 22.1 (6.7) 17.7 (3.4)
Crown volume scorched (%) 48.5 27.7 17.4 3.4
Cambial damage (number of quadrants of bole with dead cambium) 3.0 2.2 0.6 0.3

The number of dead cambium samples was the best predictor of mortality. The percentage crown scorch was a better predictor than scorch height and can be used along with tree diameter to form easily applicable models [225]. 

Three years after the fires the average cover of Rocky Mountain Douglas-fir seedlings was 0.1% on unburned plots; 0.03% on moderately burned (variable damage to shrubs and duff layer) plots; 0.17 percent on severely burned (mineral soil exposed) plots; and no seedlings established on "lightly burned" (minimal damage to shrubs and duff layer) plots [244]. Nutrient analyses of prefire and postfire soil, soil water, and some plants are described in Stark [225] and Stark and Steele [226].

Eight years after the fires, analysis of Rocky Mountain Douglas-fir radial area growth was performed [225]. Rocky Mountain Douglas-fir's relative radial increment on burned plots was about equal to that on unburned plots in the 1st year and slightly greater on burned plots thereafter. Rocky Mountain Douglas-fir's response was less positive than that of western larch. The relative radial increment of Rocky Mountain Douglas-fir trees on burned plots was greater than that of trees on unburned plots but not statistically (p>0.05) significant [213]. The average unadjusted radial growth increment of Rocky Mountain Douglas-fir trees on burned and unburned plots for the first 8 years after treatment is given below:

Year

Burned

Unburned

inches cm inches cm
1 0.021 0.053 0.021 0.054
2 0.026 0.066 0.025 0.063
3 0.03 0.075 0.031 0.079
4 0.024 0.061 0.021 0.054
5 0.024 0.062 0.023 0.059
6 0.024 0.060 0.020 0.052
7 0.024 0.061 0.019 0.049
8 0.032 0.082 0.030 0.076

FIRE MANAGEMENT IMPLICATIONS:
Underburning in similar western larch/Rocky Mountain Douglas-fir forests is feasible from a control perspective and useful for fuels reduction and thinning. After 8 years 50% of trees were dead; the best predictor of mortality was bole damage which may be at least partially controlled in prescribed fire settings. Within the range of fuel loadings in this study, fires were most manageable and still effective when the moisture content of 0- to 1-inch (0-2.5 cm) dead fuels was around 15%. Strip ignition helped overcome control and ignition problems caused by discontinuous concentrations of heavy fuels. Underburning required attention to the form, moisture status, and amount of living vegetation [225]. Detailed prescriptions for underburning are given in Norum [192]. 


2nd CASE STUDY:

CASE NAME:
Miller Creek-Newman Ridge: Prescribed fire and wildfire in a western larch/Rocky Mountain Douglas-fir stand

REFERENCES:
Beaufait, W. R.; Hardy, C. E.; Fischer, W. C. 1977 [35]
DeByle, N. V. 1981 [71]
Shearer, R. C. 1975 [234]
Shearer, R. C. 1976 [235]
Shearer, R. C. 1982 [237]
Shearer, R. C. 1984 [238]
Shearer, R. C. 1989 [240]

FIRE CASE STUDY AUTHORSHIP:
Crane, Marti. April 1991. 

SEASON/SEVERITY CLASSIFICATION:
May through October/low to very severe

STUDY LOCATION:
Two study locations were used. The 1st contained 641 acres in the Miller Creek and Martin Creek drainages of the Flathead National Forest of northwestern Montana. This is referred to as the Miller Creek area. The 2nd location consisted of 526 acres on Newman Ridge located between Two Mile Creek and Ward Creek on the Lolo National Forest near the border of western Montana and Idaho.

PREFIRE VEGETATIVE COMMUNITY:
Most of Miller Creek was considered to be in 1 of 3 phases of the subalpine fir (Abies lasiocarpa)/queencup beadlily (Clintonia uniflora) habitat type. The fool's huckleberry (Menziesia ferruginea) phase was found on higher middle and upper north- and east-facing slopes. The beargrass (Xerophyllum tenax) phase was on drier south and west aspects and the queencup beadlily phase on most other sites. Stream bottoms belonged to the western redcedar (Thuja plicata)/queencup beadlily habitat type. The dominant conifers were Rocky Mountain Douglas-fir (Pseudotsuga menziesii var. glauca), western larch (Larix occidentalis), and Engelmann spruce (Picea engelmannii) with some Rocky Mountain lodgepole pine, grand fir (Abies grandis), and subalpine fir. The western larch/Rocky Mountain Douglas-fir cover type occupied over 50% of the area [35].

On Newman Ridge 7 habitat types were identified. The warmest and driest was the Rocky Mountain Douglas-fir/ninebark (Physocarpus malvaceus) habitat type on convex southwest slopes. Other habitat types included grand fir/queencup beadlily on concave east, northwest, and protected south-facing slopes; grand fir/beargrass on upper west-facing slopes; western redcedar/queencup beadlily habitat type, fool's huckleberry phase on concave north- and northeast-facing slopes; Douglas-fir/big huckleberry habitat type beargrass phase on upper south-facing slopes; subalpine fir/queencup beadlily habitat type, fool's huckleberry phase on north slopes along the ridge; and subalpine fir/beargrass habitat type, big huckleberry phase on south slopes near the ridge. Dominant conifers were Rocky Mountain Douglas-fir, larch and Rocky Mountain lodgepole pine with some Pacific ponderosa pine, grand fir, subalpine fir, western white pine (Pinus monticola), Engelmann spruce and western redcedar. The composition of prefire stands at Newman Ridge included 34% Rocky Mountain Douglas-fir [71].

TARGET SPECIES PHENOLOGICAL STATE:
Fires were prescribed in May through October affecting Rocky Mountain Douglas-fir individuals in a variety of phenological states.

SITE DESCRIPTION:
Elevation at Miller Creek ranges from 4,200 to 5,000 feet (1,280-1,524 m) with slopes averaging 24% and ranging from 9 to 35%. Soils are Andic Cryoboralfs that developed in glacial till from the argillites and quartzites of the Wallace (Belt) formation. Average precipitation is about 25 inches (640 mm) annually; approximately two-thirds falls as snow during the long cool winter. Elevation at Newman Ridge ranges from 4,400 to 5,400 feet (1,341-1,646 m) with slopes averaging 55% and ranging from 44 to 76%. Soils are Andic Cryochrepts that have developed in place or in colluvium from argillites and quartzites of the Belt formation. There is a surface loess deposit containing ash from the Mt. Mazama and Glacier Peak volcanic eruptions at both sites. Deposits are 0.5 to 2.5 inches (1-6 cm) thick at Miller Creek and 2 to 3 inches (5-8 cm) thick at Newman Ridge. Average precipitation is nearly 40 inches (1,020 mm) at Newman Ridge, of which 2/3rds falls as snow [35]. 

Sixty 10-acre (4-ha) treatment units were established at Miller Creek, and 16 units, ranging in size from 20 to 58 acres (8-24 ha), were established at Newman Ridge. The sites faced in various aspects with equal representation. The units were clearcut, slashed and burned. Fuel loads after clearcutting and before fire, excluding duff, ranged from 60 to 165 tons per acre (135-370 t/ha). Mean fuel loads are described below [35]:

Fuel class

Miller Creek fuel consumption

Newman Ridge fuel consumption

Prefire (tons/acre) Quantity burned (tons/acre) Percentage consumed Prefire (tons/acre) Quantity burned (tons/acre) Percentage consumed
needles 1.54 1.54 100 1.56 1.56 100
Duff (0 to 1 cm) 1.29 1.12 87 1.14 1.05 92
Duff (1-10 cm) 9.84 6.78 69 12.1 10.62 88
Duff (> 10 cm) 101.27 59.6 60 93.5 51.66 55
Total 113.94 69.04 61 108.29 64.89 60

FIRE DESCRIPTION:
Fires were prescribed as an assessment of site preparation and conifer regeneration techniques in western Montana. At both Miller Creek and Newman Ridge fires were prescribed on various plots throughout the year from May to October over 3 years [35]. Slash fuels were allowed to cure for an average of 9 months before burning (2 to 18 months range). Fuel moisture of 0 to 0.4 inch (0-1 cm) branchwood ranged from 5 to 21%. Burning patterns and fire severity varied among the plots burned. After broadcast burns at Miller Creek, 75% of the fuels less than 3.9 inches (10 cm) burned and 60% of the larger fuels burned. At Newman Ridge 89% of the fuels less than 3.9 inches (10 cm) burned and 55% of the larger fuels burned. Greater surface soil heating occurred at Newman Ridge than at Miller Creek because the duff layer was shallower and water content of both duff and soil was lower. The average duff reduction ranged from 36 to 70% at Miller Creek and 44 to 99% at Newman Ridge. In 1967 a wildfire burned 5 units that had been clearcut and 4 units that were uncut at Miller Creek. Average duff reduction from the wildfire was 93% with a range of 84 to 100% [35,71]. 

FIRE EFFECTS ON TARGET SPECIES:
Mortality of Rocky Mountain Douglas-fir was not assessed, but rather the usefulness of prescribed fire for site preparation and regeneration. The 1967 wildfire consumed most of the duff. Other fires were spotty and exposed some mineral soil. Fewer Rocky Mountain Douglas-fir seedlings established on unburned duff than on mineral soil. Unburned duff continued to decrease for several years, exposing bare soil on areas where the fire had left charred duff. The reasons for this decrease may include increased decomposition stimulated by warmer surface temperature during May and June where adequate moisture was present; redistribution by precipitation, runoff or wind; and oxidation. In addition to natural seeding, seeds were sown in 1967 on test plots and bare root seedlings were planted on Newman Ridge from 1970 through 1975 and on four clearcuts at Miller Creek from 1970 through 1973. Postfire seed dispersal into the clearcuts from Rocky Mountain Douglas-fir in the timber around clearcut areas was good. Over half of the seed dispersed into clearcuts at Newman Ridge was Rocky Mountain Douglas-fir. The best seed year was 1971 when 39% of the Rocky Mountain Douglas-fir seed dispersed at Newman Ridge was sound, compared with an average of 11% in other years [35,193]. The cumulative average number of sound seed of Douglas-fir from 1969 through 1974 on eight clearcuts on Newman Ridge by distance was 21,700 seeds/acre within 200 feet (61 m) of clearcut edge, 10,300 between 200 and 400 feet (61 to 122 m), 4,200 between 400 and 600 feet (122 to 183 m), and 8,400 between 600 and 800 feet (183 to 244 m) [71].

Germination of Rocky Mountain Douglas-fir began at snowmelt or soon after and was greater on mineral soil than on unburned duff more than 0.5 inch (13 mm). Seed and seedling losses were caused by rodents, drought, frost heaving, high temperatures at the soil surface and migrating juncos that ate emerging seedlings in 1968. Drought was the leading cause of mortality on south-facing slopes and second highest on other aspects. In 1978 at Miller Creek, stocking of Rocky Mountain Douglas-fir seedlings averaged 32% on burned units and 8% on unburned clearcuts. By 1984 at Miller Creek, stocking of established seedlings of Rocky Mountain Douglas-fir averaged 61% on burned units and 6% on unburned clearcuts. In 1979 at Newman Ridge, stocking of established Rocky Mountain Douglas-fir seedlings averaged 34% (range was 7% to 63%) on burned clearcuts. Aspect had a profound effect on seedling establishment: natural regeneration was lowest on south-facing slopes. The average number of established (>6 inches (15.2 cm) in height) Rocky Mountain Douglas-fir seedlings in 1984 on 37 burned units at Miller Creek and on 7 burned clearcuts at Newman Ridge by aspect was [240]:

  North East South  West
Miller Creek  

#/acre

764 746 652 1,118

#/ha

1,888 1,843 1,611 2,783
Newman Ridge  

#/acre

884 289 129 523

#/ha

2,184 714 319 1,292

Although the original stocking of Rocky Mountain Douglas-fir was less than its stocking in the original stand, new seedlings have continued to establish and stocking is becoming larger in many clearcuts. By 1984 at Miller Creek, Rocky Mountain Douglas-fir seedlings were 26% of all natural regeneration. The same year at Newman Ridge, Rocky Mountain Douglas-fir seedlings were dominant at 56% of all natural regeneration. The number of young seedlings suggests that this dominance will continue. Rocky Mountain Douglas-fir seedlings are shorter than western larch and Rocky Mountain lodgepole pine seedlings but similar in size to Engelmann spruce and taller than grand fir or subalpine fir. At Miller Creek in 1978, Douglas-fir seedlings averaged 1.8 feet (0.5 m) with a range of 6.4 to 0.5 feet (2.0-0.2 m) while at Newman Ridge in 1979, the tallest Rocky Mountain Douglas-fir seedlings averaged 2.1 feet (0.6 m). At Miller Creek regeneration varied significantly by habitat type and phase. More than twice as many Rocky Mountain Douglas-fir seedlings and saplings were growing on the western redcedar/queencup beadlily habitat type as on the queencup beadlily phase of the subalpine fir/queencup beadlily habitat type. There were 470 to 527 more stems per acre (1,161-1,302 more/ha) on the queencup beadlily phase of the subalpine fir/queencup beadlily type than on the fool's huckleberry or beargrass phases. At Newman Ridge more Douglas-fir regeneration grew on the western redcedar/queencup beadlily habitat type with the poorest Rocky Mountain Douglas-fir regeneration on the 2 Rocky Mountain Douglas-fir habitat types [240].

FIRE MANAGEMENT IMPLICATIONS:
The study demonstrates the value of prescribed fire for site preparation and Rocky Mountain Douglas-fir regeneration. During late spring and early summer, duff is usually wet and fires do not expose much mineral soil. Late summer or early fall fires are more effective at removing duff and exposing mineral soil. However, if precipitation occurs, fuels and duff need to dry for several days. At Newman Ridge, moderate severity fires removed most of the duff and prepared an adequate seedbed. At Miller Creek, the same severity fire exposed less mineral soil because the duff was thicker and wetter. Habitat type and site conditions alter the amount of duff removal needed. On mesic habitat types hot fires that expose a high proportion of mineral soil, followed by good seed years, led to overstocking. On steeper slopes with drier conditions, such as at Newman Ridge, residual duff layers have more adverse impact on the survival of seedlings. While Rocky Mountain Douglas-fir establishment during early postfire years was best on fire-exposed, mineral soil, Rocky Mountain Douglas-fir benefited least of the conifers from exposure of mineral soil. The hardest areas to regenerate at either location were the Rocky Mountain Douglas-fir habitat types at Newman Ridge. These sites were the driest areas in this study. Seed dispersal should be taken into account when deciding the time of fall fires. In a good seed year, dispersed seed could be destroyed by fires after early September at lower elevations and a few weeks later at higher elevations [35,71].

Species Index
FEIS Home

Related categories for SPECIES: Pseudotsuga menziesii var. glauca | Rocky Mountain Douglas-Fir

Send this page to a friend
Print this Page

Content on this web site is provided for informational purposes only. We accept no responsibility for any loss, injury or inconvenience sustained by any person resulting from information published on this site. We encourage you to verify any critical information with the relevant authorities.

Information Courtesy: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory. Fire Effects Information System

About Us | Contact Us | Terms of Use | Privacy | Links Directory
Link to 1Up Info | Add 1Up Info Search to your site

1Up Info All Rights reserved. Site best viewed in 800 x 600 resolution.