Damage to First- Year Conifers 

 Under Three Livestock Grazing 

 Intensities in Idaho 



James L. Kingery 

 Russell T. Graham 

 Jeffrey S. White 



INTRODUCTION 



Grazing of forestland is a traditional resource use in the 

 Northern Rocl<y Mountains and much of the Western 

 United States (Tisdale 1961). These lands have potential to 

 produce large amounts of forage in response to moderate 

 to high precipitation (McLean 1974). As a multiple-use 

 aspect of these lands, forage production and grazing are 

 important and valid uses of many of these areas (Mitchell 

 1982). Although grazing may be of equal or greater eco- 

 nomic importance than timber production on drier sites 

 (Clary and others 1975), it usually has lower value than 

 timber production on mesic and wet sites that are common 

 in northern and central Idaho (USDA FS 1984; Eissenstat 

 and others 1982). 



A major concern of forest resource managers is the com- 

 patibility of livestock grazing with intensive forest man- 

 agement. The premise that grazing may damage both 

 natural and artificial tree regeneration, as well as cause 

 soil compaction that may interfere with tree development, 

 is a common concern of those responsible for regenerating 

 cutover areas (Edgerton 1971). The general consensus is 

 that on sites more favorable for regeneration closely con- 

 trolled livestock grazing may be compatible with tree 

 establishment (Adams 1975). But on sites where regenera- 

 tion is sparse or difficult to obtain, grazing is incompatible 

 until there is an adequate stocking of trees large enough 

 to withstand grazing (USDA FS 1982). 



Although research studies are constantly adding to our 

 knowledge of forest and range management, few studies 

 truly integrate these values (Kingery 1983). Consequently 

 much of the research that has been done simply reinforces 

 the conviction that livestock use is either compatible or in- 

 compatible with intensive forest management. 



A number of studies specifically address grazing impact 

 on tree seedlings. There is a great deal of variability in 

 research methods and study results (USDA FS 1982). 

 Wellner (1969) stated that "the question of grazing and 

 tree regeneration is quite inconsistent and controversial; 

 one can get almost any answer he wishes from the 

 literature." 



To provide more definitive information on the grazing- 

 reforestation issue, an investigation was established to 

 determine the effects of livestock grazing on the factors 

 that influence the establishment and growth of seedlings. 

 The study was located on cutover lands on the Nez Perce, 

 Clearwater, and Idaho Panhandle National Forests. The 

 study considered: concentration of animals; duration and 

 timing of grazing; terrain, soil, and ground vegetation; 



and tree species and size. This report covers findings of 

 the first year of study, generally considered to be the 

 most crucial period of seedling survival. 



METHODS 

 Study Areas 



Areas were selected that have a high potential for both 

 forage production and growth of commercial timber. Study 

 areas were located in central and northern Idaho in three 

 different habitat types (Cooper and others 1985) to repre- 

 sent a wide range of conditions. The first study area was 

 located in a Pseudotsuga menziesii/Physocarpus malvaceus 

 habitat type, which reflected fairly dry and warm condi- 

 tions; the second study area was located in an Abies 

 grandis/Clintonia uniflora habitat type, a mesic or inter- 

 mediate set of conditions; study area 3 was located in a 

 Thuja plicata/Clintonia. uniflora habitat type, character- 

 ized by cool, moist conditions. 



Within each of these study areas, three uniform sites 

 were located to represent different livestock grazing in- 

 tensities (light, medium, and heavy). Within each grazing 

 intensity, a 0.4-ha plot was located. Field observation and 

 records on the history of grazing use were used to select 

 sites within each habitat type. Actual forage utilization at 

 each of the study sites was determined at the end of the 

 first grazing season. 



Study Area 1: Indian Springs— The Indian Springs 

 study area is in the Squaw Creek drainage of the Slate 

 Creek Ranger District, Nez Perce National Forest. The 

 area is part of the Salmon River breaks, and the general 

 topography is quite steep, with mass wasting evident. 

 Slope of the study area ranges from to 50 percent, with 

 an average slope of approximately 25 percent. 



Majority of the soils on the study area are Typic Argix- 

 erolls, fine loamy mixed frigid family, which are moderate- 

 ly to well drained. Due to the mass wasting and erosion in 

 the area, some soils have a thin surface layer. 



The climate for this vicinity is subhumid, with warm dry 

 summers and cool wet winters. The majority of the pre- 

 cipitation falls during the winter, with July and August 

 being the driest months. The estimated annual precipita- 

 tion for the area is approximately 45 cm. The mean annual 

 air temperature for the study site is 9 °C. 



The Indian Springs study area is in the Pseudotsuga 

 menziesii/Physocarpus malvaceus habitat type, Calama- 

 grostis rubescens phase, as described by Cooper and others 

 (1985). An overstory of Douglas-fir {Pseudotsuga menziesii 



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