(1) The department shall use a site-specific model that incorporates ecological characteristics through habitat and cover types to describe cover type representation. Cover type is one characteristic that describes desired future conditions. When run at the administrative unit level, the model describes a desired future condition in terms of cover type representation. The cover types defined are white pine, ponderosa pine, Douglas-fir, western larch/Douglas-fir, lodgepole pine, mixed conifer, and subalpine types. Where data do not allow unit-level descriptions, then project-level data and descriptions will be utilized.
(a) The model indicates the approximate number of acres of each cover type that represents a desired future condition for the unit as a whole. Treatments shall be determined at the project level. The department shall use local knowledge to improve estimates as necessary, such as identification of hardwood cover types as a desired future condition.
(i) The following describes the model referred to in (1) . Each stand is tested sequentially against the following criteria. Once a stand is assigned it does not go through any of the subsequent steps.
(A) If white pine makes up 10% or greater of any of the four main species, the white pine type is assigned.
(B) If ponderosa pine makes up over 20% of the cover, the ponderosa pine cover type is assigned.
(C) If western larch represents a minimum of 10% of the stand, or any stand that has at least 30% cover represented by western larch and Douglas-fir, the western larch/Douglas-fir type is assigned.
(D) If Douglas-fir represents 50% or greater, the Douglas-fir type is assigned.
(E) If lodgepole pine represents 40% or greater, the lodgepole pine type is assigned.
(F) If the stand is not yet assigned and the habitat type is greater than 630, the subalpine type is assigned.
(G) All remaining stands are assigned to the mixed conifer type.
(b) The department shall consider stands in all age classes for treatment to promote appropriate conditions. One tenet of achieving biodiversity goals at the landscape level is the presence of stands in all age classes.
(c) The department shall select desired future stand structural conditions at the project level, and shall consider disturbance regimes in terms of frequency and severity (see ARM 36.11.408) . The department shall assess stand structure at the project level and track quantities of various structures at the unit level, to the extent data are available.
(i) The department shall use the stand structure definitions as described in the department's stand level inventory.