More intensive management could be applied to many young stands in conifer forests of the Northern Rockies. Vast areas are stocked with stands that contain a mixture of conifer species. An important mixed species cover type in this region is the western larch type (formerly called the larch-Douglas-fir type) (Society of American Foresters 1980). It is usually dominated by western larch (Larix occidentalis Nutt.) and Douglas-fir (Pseudotsuga menziesii var. glauca [Beissn.] Franco); but also has appreciable amounts of Engelmann spruce (Picea engelmanii Parry) and subalpine fir (Abies lasiocarpa [Hook.] Nutt.). Species sometimes occurring in the cover type are lodgepole pine (Pinus contorta var. latifolia Engelm.), western white pine (Pinus monticola Dougl.), western hemlock (Tsuga heterophylla [Raf.] Sarg.), and western redcedar (Thuja plicata Donn ex D. Don). The exact species composition in the western larch type is determined largely by the successional stage of the stand and the physical environment in which the stand occurs. Usually the above-mentioned mixture of conifer species occurs in habitat types of the Pseudotsuga menziesii and Abies lasiocarpa successional series (Daubenmire and Daubenmire 1968; Pfister and others 1977).