Ten mountain lakes were analyzed in order that they be assigned a trophic status. The lakes which are located in the Mount Hood National Forest of Oregon are Anvil, Beaver Pond, Cripple Creek, Fish, Gifford, Monon, Ollalie, Rimrock, Round, and Sportsman. The purpose of this report is to determine the productivity of these waters. Data were collected for analyses of temperature, dissolved oxygen concentration, Secchi depth, major ion concentration, light intensity versus depth, alkalinity, phytoplanktcn species composition/total density, and zooplankton species composition/total density. Samples were collected in Van Darn sampling bottles and returned to the laboratory for chemical analyses and taxonomic identification of biological organisms. Field profiles were taken for light intensity, temperature, dissolved oxygen concentration, specific conductivity, and depth using portable electronic equipment. A Secchi disk was used in the field for obtaining light extinction data. The lakes were assigned a trophic status according to carlson's Trophic State Index (Carlson, 1977). Beaver Pond Lake which is the most productive lake of the 10 surveyed had an average Secchi depth of 1.7 meters, an average soluble reactive phosphorous concentration of 59.8 ug/L, and an average chlorophyll-a concentration of 29.3 ug/L for the dates sampled. These values are consistent with lakes which are eutrophic. Ollalie Lake had an average Secchi depth of 13.2 meters, an average soluble reactive phosphorous concentration of 1.64 ug/L, and an average chlorophyll-a concentration of 0.28 ugfL. This lake is ultraoligotrophic-to-oligotrophic according to the Carlson index. The other lakes of the study were assigned values for trophic state which are somewhere between those assigned to Beaver Pond and Ollalie lakes. The 10 lakes studied for this report were compared to lakes studied for the compilation of the Western Lake survey (Landers, et. al. 1987). It was noted that Beaver Pond, Round, and Sportsman lakes are nutrient rich while Monon, Ollalie, and Gifford, are nutrient poor when compared to other lakes located in the Pacific Northwest. Anvil, Cripple Creek, Fish, and Rimrock lakes have profiles consistent with the majority of mountain lakes located in the area.

The ability of northern goshawks (Accipiter gentilis) to persist in intensively managed and selectively harvested forest habitats is largely unknown. To address the concern that populations of northern goshawks in eastern Oregon may be declining in response to habitat alteration, I studied occupancy rates and habitat relationships of nesting goshawks on the Fremont National Forest and adjacent private lands during 1992-1994. My objectives were to determine if historic territories (i.e., those occupied ��� 1 season during 1973-1991) were still occupied, document current site conditions and quantify changes in forest cover on those territories between 1973-1994, and compare present conditions of forest vegetation between nest sites that were currently occupied and those where I did not detect the presence of territorial goshawks (no-response sites). In 1994, I surveyed a forest-wide random sample of 51 historic nest sites, stratified by forest cover type. Occupancy of historic sites by goshawks was 29% (15 of 51), compared to 79% (30 of 38) mean annual occupancy rate of current territories (found initially during 1992-1994). Across all strata, 86% of current nest sites (n=38) were in Mid-aged or Late structural stage forest (trees >23 cm DBH) with >50% canopy closure. Among the historic territories used for analysis (n=46), those found occupied (n=15) in 1994 had significantly more Mid-aged Closed forest (average stand DBH 23-53 cm, <15 trees per ha >53 cm DBH; >50% canopy closure) and Late Closed forest (15 trees per ha >53 cm DBH; >50% canopy closure) than no-response sites (n=31). This relationship was significant (P<0.05) for circular scales of 12, 24, 52, 120, and 170 ha surrounding goshawk territory centers. Within the 52 ha scale around historic nest sites surveyed in 1994, occupied sites had 49% (SE=6.6) total Late Closed and Mid-aged Closed forest, while sites with no response had 19% (SE=3.0) total Late and Mid-aged Closed forest. Historic sites had 51% (SE=3.8) total Late and Mid-aged Closed forest when last known occupied before 1992. Among historic territories, mean percent area of habitat in Late Closed forest at the 12 ha nest stand scale was 4 times greater in occupied (27%) than in no-response sites (6%) (P<0.05). A logistic regression model for occupied sites confirmed the importance of Late Closed and Mid-aged Closed forests as indicators of quality habitat within the 52 ha scale on historic sites where goshawks were still present in 1994. Goshawk pairs were more likely to persist in historic territories having a high percentage of mature and older forest (about 50%) in closed-canopied conditions within the 52 ha scale, suggesting that little or no habitat alteration within aggregate nest stands is important to ensure the persistence of nesting pairs. I recommend preserving multiple nest stands within the 52 ha scale and discourage further cutting of large, late and old structure trees (>53 cm DBH) within the PFA to preserve stand integrity, maintain closed canopies, maintain connectivity to alternate nest stands, and optimize conditions for breeding goshawk pairs to persist. / Graduation date: 1998

The Quartz Mountain Obsidian Quarry is located in the Southeast corner of the Bend Fort Rock Ranger District in central Oregon, approximately forty-five miles southeast of Bend, Oregon. The research of the Quartz Mountain Obsidian Quarry began with a literature search of other quarry sites in the area and the use of aerial photos to determine the survey area. After the survey area was established a ground survey was conducted. Following the survey several key areas were chosen for surface collections that could answer key questions: What types of core reductions were being used on Quartz Mountain?; and What types of materials were being utilized? (red/black obsidian found in rhyolite veins, red/black obsidian found in fist sized and larger nodule form, or large block black obsidian). In order to answer these questions three collection units were established. The lithic material from the units was collected and analyzed and the information placed into a database, which was then grouped for statistical analysis, and generated into charts and tables. The resulting data was then compared to the information found from an extensive literature search to see how the material that I collected compared to those found at other quarry sites. From this information I was able to determine that two different core reduction methods were being used on Quartz Mountain: blade core and bifacial core. Along with the different core reduction methods a mobility strategy also came into play. In this thesis I will use the data gathered to determine the different core reduction methods and the mobility strategies that are associated with them. / Graduation date: 1998

A stratified sampling method was used to study the effects of two prescribed fires on a 250-acre section at the northwest end of Fork Ridge, Hoosier National Forest, in the spring of 1993 and 1995. An unburned area at the southeast end of Fork Ridge, adjacent to the burned area, and with similar forest communities, was used as a control area. Three growing seasons after the last fire, the burned area exhibited noticeable differences in understory vegetation. Herbaceous species diversity and richness, total herb cover on mesic sites, and mean percent cover and relative frequency for mesic-site, shade-tolerant species were greater on the burned area than on the unburned area. Dry-site, shade-intolerant tree seedlings including scarlet oak (Quercus Coccina), chestnut oak (Quercus prinus), sassafras (Sassafras albi dum), and tulip poplar (Liriodendron tulipifera) had higher relative frequency in the burned area, while shade-tolerant flowering dogwood (Cornus Florida) had lower relative frequency. / Department of Biology

Since the introduction of management practices by the Forest Service to stabilize red-cockaded woodpecker (RCW) populations, the number of cavity trees killed by southern pine beetles (SPB) has increased. A model of the landscape ecology of RCW and SPB in the Homochitto National Forest was created using data collected from the Forest Service and Global Atmospherics. The conclusions of the study were that the RCW and SPB utilize the same type of habitat and the stand hazard maps are an accurate means of determining the locations of SPB infestations. The functional heterogeneity maps created for the SPB and RCW would be useful predictors of future occurrences of either species if complete data were obtained.

Final Report / Contract on 43-8371-4-628 / For: USDA, Forest Service, Southwestern Region / Regional outbreaks of western spruce budworms (Choristoneura occidentalis Freeman) have recurred at least three times in northern New Mexico since the early 1920's when the U. S. Forest Service first began systematic forest-pest surveys and documentation (Lessard 1975, U. S. Forest Service documents). The current outbreak was first noticed in a small area on the Taos Indian Reservation in 1974, and since then the defoliated areas have increased in New Mexico and Arizona to more than 370,000 acres of Federal, Indian, State and private lands (Linnane 1984). Losses in timber values can generally be ascribed to radial growth loss, height growth loss, topkilling, reduced regeneration, and mortality (Carlson et al. 1983, Fellin et al. 1983). A damage assessment project was initiated in 1978 and was aimed at obtaining measurements of some of these losses in budworm infested stands on the Carson National Forest, New Mexico (Holland and Lessard 1979). A large data base has subsequently been developed, including yearly measurements on topkilling, mortality, defoliation, and insect population changes (Stein 1980, 1981, Stein and McDonnell 1982, Rogers 1984). A growth assessment study was undertaken in 1982 to determine the feasibility of using dendrochronological methods to identify the timing of past outbreaks and to quantify radial growth losses associated with budworm defoliation (Swetnam 1984). Results of this work showed that three major outbreaks during the twentieth century were clearly visible in the tree-ring samples obtained from currently infested trees. The radial growth of host trees was corrected for age, climate and other non-budworm environmental effects, and then growth losses were computed as a percentage of expected growth (Swetnam 1984). Additional collections were obtained in 1984 in order to expand the scope of the radial growth study. The objectives included 1) assessment of a larger number of tree -ring samples, 2) comparison of radial growth losses between the two primary host species - Douglas-fir (Pseudotsuga menziesii) and white fir (Abies concolor), 3) comparison of radial growth losses between age classes, and 4) analysis of the relationship between yearly measurements of defoliation, insect populations and radial growth. This report summarizes the findings of the above analyses. Increment core samples from the 1982 collections are included here, therefore this report supersedes the earlier report (Swetnam 1984). Information is also presented on observations derived from the dated tree-ring series on the timing of occurrence of known and inferred spruce budworm outbreaks for the past 284 years (1700- 1983). This is the longest record of spruce budworm occurrence yet developed for western North America.

Soils from two active earthflows, two earthflow deposits, and three non-earthflow landforms are examined to determine if a connection exists between near-surface soil properties and rates of earthflow movement. The study area is located in the Clackamas Ranger District of the Mt. Hood National Forest in the northern Oregon Cascades. Its geology consists of clay-bearing volcaniclastic formations overlain by unaltered flows of andesite and basalt, a combination that contributed to large-scale landsliding during the late Pleistocene. Deposits from these landslides now cover much of the valley floor, and it is from these deposits that earthflows tend to mobilize. The main hypothesis is that near-surface soil properties reflect earthflow movement and may be used to distinguish between active and inactive earthflows. The results support this hypothesis and indicate that soils in each of the three categories show clear differences in terms of their physical properties. The mean field moisture content of active earthflows is 56 percent, while that of earthflow deposits is 46 percent and that of non-earthflow landforms is 36 percent. All samples from active earthflows exhibit plasticity, whereas 90 percent of samples from earthflow deposits and only 25 percent of samples from nonearthflow landforms exhibit plasticity. The mean liquid limit of active earthflows is 78 percent, compared to 60 percent for earthflow deposits and 46 percent for non-earthflow landforms. The mean plasticity index of active earthflows is 41 percent, compared to only 13 percent for earthflow deposits and non-earthflow landforms. These differences are largely attributed to clay content and clay type. The mean clay content of active earthflows is 46 percent, compared to 24 percent for earthflow deposits and only 5 percent for nonearthflow landforms. In contrast, the mean sand content of active earthflows is 20 percent, while earthflow deposits contain 40 percent and non-earthflow landforms 50 percent. This difference in particle sizes is reflected in friction angle. Active earthflows have a mean friction angle of 15 degrees, compared to 24 degrees for earthflow deposits and 31 degrees for non-earthflow landforms. These results indicate that soil properties can be used to draw distinctions between active and inactive earthflows. However, soil properties are much less effective at distinguishing between active earthflows that move at different rates. For example, Junction earthflow, which moves only a few centimeters per year, is composed of soils that indicate it to be less stable than the Collowash earthflow, which moves approximately 2 meters per year. The reason for this discrepancy is that, in addition to soil properties, the rate of earthflow movement depends on the complimentary effects of hydrology, slope angle, toe erosion, and boundary roughness. Many ancient landslide deposits in the Mt. Hood National Forest are poised for action and may mobilize upon the slightest provocation. Since this is not seen as a "desired future condition" there is a need to differentiate between those deposits with a potential for reactivation and those likely to remain dormant. Examining the physical properties of soils appears to be one way to do this, and the information collected is valuable to land managers and earth scientists alike.

No description available.

Six species of insects were found attacking limber pine cones from July 26, 1968, through October 4, 1969, in Cache National Forest. The three species considered of major importance are: Conophthorus flexilis Hopkins, Dioryctria abietella (D. & S.), and D. sp. near or disclusa Heinrich. The three minor species encountered are; Bradysia sp., Trogoderma parabile Beal, and Asynapta keeni (Foote). In addition to the major and minor cone pests three parasites, Apanteles sp . prob. starki Mason, Elacherus sp., and Hypopteromalus percussor Girault were found associated with the cone pests. C. flexilis, which completely destroys the cone, was ranked as the number one pest on the basis of numbers present plus severity of damage. During 1968 and 1969 C.flexilis destroyed 11.47 percent of the 1500 cones examined, with a mean of 5.87 larvae per infested cone. The cone moths, D. abietella and D. sp. near or disclusa, were ranked second and third in importance respectively. D. sp . near or disclusa was potentially the more important cone moth, as it caused a total destruction of the seed bearing portion of the cones. However, D. abietella infested 15.40 percent of the cones, in contrast to 2.00 percent by D. sp. near or disclusa. There were no significant statistical differences in insect populations between 1968 and 1969, although the percent infestation of C. flexilis and D. sp. near or disclusa increased slightly and D. abietella decreased.

Forest harvest can have significant impacts on forest ecosystems that may influence the capacity of soils to sequester carbon (C). The microbial community controls decomposition, which is a critical process in partitioning litter- and root-C between CO₂ and storage in semi-permanent soil-C pools. The objectives of this study were to determine the effect of clear-cutting and stand age on: 1) temporal dynamics of soil microbial community (SMC) structure and physiological status; and 2) shifts among microbial functional groups in taking up ¹³C-labeled plant materials during decomposition. The experiment was conducted in Douglas-fir ecosystems within the Gifford Pinchot National Forest, Washington. We chose stands of three different ages: old-growth where trees are between 300 and 500 years old; an 8-year old stand; and a 25-year old stand. Phospholipid fatty acid (PLFA) profiling and ¹³C-PLFA labeling techniques along with the ratio of saturated to monounsaturated PLFAs and the ratios of cyclopropyl PLFAs to their monoenoic precursors as microbial physiological stress markers were utilized. Microbial PLFA profiles showed that SMC structure and physiological status was most affected by season and secondarily by time since clear-cutting. Total microbial biomass and bacterial and fungal biomass were significantly reduced in CC8 but not in CC25 sites relative to old-growth sites. Total microbial biomass concentration was lowest and the stress indicators were highest in August, which corresponded to low soil moisture and high temperatures. The relative amount of ¹³C incorporated into PLFAs was also influenced by stand age and ¹³C source (¹³C-labeled litter vs. ¹³C-labeled root material). A significantly greater amount of ¹³C was incorporated in CC8 samples compared to OG1 samples in five out of the seven sample dates. Additionally, a significantly greater proportion of ¹³C was incorporated into soil samples containing the ¹³C-labeled litter material relative to samples containing ¹³C-labeled root material in four out of the seven dates. In general, 18:lω9 and 18:2ω6,9 (common fungal biomarkers) had the greatest amount of ¹³C incorporation throughout the study period in both clear-cut and old-growth sites, indicating the important role of fungi in the decomposition of litter and root material and translocation of C within soil layers. / Graduation date: 2006