• CASE NAME
• SEASON/SEVERITY CLASSIFICATION
• STUDY LOCATION
• PREFIRE VEGETATIVE COMMUNITY
• TARGET SPECIES PHENOLOGICAL STATE
• SITE DESCRIPTION
• FIRE DESCRIPTION
• FIRE EFFECTS ON TARGET SPECIES

CASE NAME:

White Cap Creek, Idaho

REFERENCE:

Merrill, E. H.; Mayland, H. F.; Peek, J. M. 1980 [50]

SEASON/SEVERITY CLASSIFICATION:

late summer/moderate

STUDY LOCATION:

The fire occurred in the Upper Selway River (White Cap Creek) drainage, Idaho. The area is a portion of a fire management zone in the Selway-Bitterroot Wilderness where fires are allowed to burn under natural conditions.

PREFIRE VEGETATIVE COMMUNITY:

The fire occurred in a ponderosa pine (Pinus ponderosa) forest and adjacent montane grassland. Important understory species included western yarrow (Achillea millefollium), bluebunch wheatgrass (Pseudoroegneria spicata), arrowleaf balsamroot (Balsamorhiza sagittata), cheatgrass (Bromus tectorum), and junegrass (Koeleria macrantha).

TARGET SPECIES PHENOLOGICAL STATE:

unknown but most likely in flowering and seed ripening stages

SITE DESCRIPTION:

Aspect: south
Elevation: 3,200-4,160 feet (1000-1300 m)
Average annual precipitation: 760 mm, with peaks occurring from November to January and April to June

Soils are derived from Idaho batholith parent material consisting of decomposed granite, gneiss, and rhyolite. They are described as low in fertility, water-holding capacity, and of weak structure.

FIRE DESCRIPTION:

The fire occurred under extremely dry conditions, with relative humidity as low as 11%, maximum temperatures of 87 degrees Fahrenheit (32^oC), and winds gusting up to 27 miles/h (45 km/hr). The fire was a lightning-ignited and began 10 August, 1973, and burned for 43 days until extinguished by rain. The fire burned quickly and little ash was left.

FIRE EFFECTS ON TARGET SPECIES:

Cover and frequency of western yarrow were equal to or lower than those on unburned sites during the 1st postfire year, but by the 3rd postfire year were greater than on unburned sites:

postfire     % Cover (+/- S.D.)     % Frequency (+/- S.D.)
  year       burned   unburned      burned        unburned
--------     ------------------     ----------------------
   1          2 (2)   2 (2)         5 (4)         5 (2)
   3          12 (12) 4 (5)         11 (5)        6 (12)

Related categories for SPECIES: Achillea millefolium | Western Yarrow