Information on the vegetation for the plan is provided by a stand level inventory of the tract. This inventory consists of a grid of 1200 permanent sample plots (one plot per 2 acres) that were installed on the tract in 1983. A portion of these plots are remeasured each year. This inventory was designed to provide training opportunities for students, as well as data for management planning, research and demonstration opportunities and growth and yield research.
Measurements from the nested fixed and variable radius plots are stored in a database that provides information on stand structure and volume that is used to develop and evaluate silvicultural prescriptions (Marshall, Johnson, and Hann, 1998). For this plan, all stands on the tract were inventoried between 1983 and 1997 and grown to current conditions using the SMC version of the ORGANON inventory projection program (Hann, 1995).
Table1. Existing Forest Inventory. (MMBF)
| Age Class | Tot. D-Fir | Tot. Hemlock |
| 0-20 | 0.02 | 0.01 |
| 21-40 | 0.34 | 0.30 |
| 41-60 | 6.21 | 4.35 |
| 61-80 | 41.24 | 21.89 |
| 81-120 | 2.74 | 2.55 |
| Total | 50.55 | 29.11 |
Figure 2. Current age class distribution.
Figure 3. Existing Stand Structural Condition.
Northern spotted owls The Blodgett Tract has areas that may be suitable for spotted owl nesting, roosting and foraging. There is a large amount of dead wood to help support prey populations, and some areas of the forest have trees with nesting platforms that have resulted from bear damage and ice storms.
The tract has been surveyed every year since 1990 for spotted owls. Responses were recorded in 1990, 1994 and 1998. These birds were not located in the follow-up surveys. As a result of this survey work the Research Forest believes that there are no active spotted owl sites on the property at this time. Annual surveys are planned to continue.
Marbled murrelets
Surveys for murrelets were completed in 1995 and 1996 on units that were scheduled
for harvest. No murrelets were observed. There are very few suitable nest
trees for murrelets on the tract, so these surveys have not been continued.
The Fishhawk drainage system was identified as an Aquatic Diversity Area by the American Fisheries Society (AFS), Essential Salmonid Habitat by Division of State Lands (DSL), a Source Watershed by the Oregon Department of Fish and Wildlife (ODFW) and a Core Salmon Area (CSA) for coho salmon in the Oregon Plan.
When ODFW surveyed the Fishhawk drainage in 1996 they found an adult abundance of > 30 coho/mile which is considered very good for the Nehalem Basin. Based on Tom Nickelson’s coho model, there are >2000 smolts/mile predicted on the main Fishhawk Creek system. McCoon Creek has > 21,000 smolts/mile predicted.
Habitat on our portion of Fishhawk Creek is generally regarded as fair to good. There is adequate shade, but few big conifers in the riparian area to contribute dead wood in the future. The desired volume of woody debris exists, but it is mostly distributed in smaller (>3m x 0.15m) single pieces rather than large key pieces (10m x 0.6m) in complex debris jams. There is less than the desired percent gravel and greater than desired percent silt, sand and organics.
The high percentages of silt and sand are mainly due to the incompetent bedrock which underlies the forest and a legacy of throughfills found in old railroad grades. Only two throughfills exist on the forest but numerous throughfills are located on the surrounding ownerships with many located upstream of the Blodgett Tract. The throughfills on the forest will be monitored by forest staff and they will be managed on a case-by-case basis.
The geology of the Blodgett Tract is such that the frequency of mass wasting is not likely to be influenced by vegetative cover. The major source of controllable erosion from ongoing forest management is roads. Maintenance and reconstruction of existing roads is a high priority and the construction of new roads will be in such a manner that chronic accelerated erosion is minimized. These activities will take place within the framework of the Oregon Forest Practice Rules and will be technically and economically feasible.
Baseline temperature data was collected for Fishhawk, the North Fork of Fishhawk and two of its tributaries, Trestle, and Wrongway Creeks, because these are tributaries of the Nehalem River which is considered water quality limited for temperature by the Department of Environmental Quality. Maximum stream temperatures were below the 64 degree State water quality standard on all of the days and all stream locations monitored. The planned management activities are unlikely to influence the range of temperatures occurring in fish-bearing streams on the Blodgett Tract.
The Blodgett Tract is located predominantly within the Fishhawk watershed and drains into the Nehalem River, however the northernmost part of the tract occupies the ridge between the Nehalem and Columbia River watersheds and a small portion of the forest drains into the Columbia River. Most of the tract is drained by the Fishhawk, North Fork Fishhawk, Trestle and Wrongway Creeks.
The Tract is underlain by marine sedimentary rock. The rock is composed of tuffaceous silts and sands that were derived from sand and volcanic debris from landmasses to the east, and were laid down when this area was shallow sea. There are intrusions of basalt in the sedimentary rock that were intruded when the rock was still submarine. These basalt intrusions show up in road cuts on an irregular basis. The sandstone is very incompetent and thus weathers easily. This is evidenced by an almost complete lack of bedrock outcrops on the forest, including the road cuts.
The terrain that has developed on the Blodgett Tract, has for the most part, gentle, rounded and short slopes. This is a legacy of the incompetent and easily weathered bedrock. For the Tract, 74% of the area has a slope less than 35%, 23% is between 36 and 60% and only 3% of the area is greater than 60% slope. Risk of a landslide greatly increases for slopes greater than 60%. Slopes 80% and greater represent terrain at high risk for debris slides. There is virtually no high risk terrain in the Blodgett Tract, which means that the tract does not support the classic debris flow/debris avalanche morphology. The tract tends to have deeper rotational-slump landslide features or earthflows as opposed to debris flows. The only shallow-translational slides observed were small features that are classed as debris slides with the slide deposit remaining at the foot of the landslide scarp that did not transition into debris flows or avalanches. The only debris avalanche observed on the tract was initiated at a large throughfill from an old, abandoned railroad grade off of the tract. The terrain does show evidence, both on the tract and immediately adjacent to it, that earthflows and rotational slumps dominate mass movement processes.
The soils on the Blodgett Tract are comprised predominantly of two series. They are the Scaponia-Braun series and the Tolke series. Both of these are deep, 40-60 inches to bedrock, well-drained, loamy soils. These soils, in combination with the abundant moisture, annual precipitation for the tract is 60-110 inches, give the tract its high site class and high productivity. The Braun series is a mesic Dystic Eutrochrept, the Scaponia series is a mesic Umbric Dystrochrept, and the Tolke series is a mesic Andic Dystrochrept.
Cultural Resources
Three types of cultural sites may, or are known to occur on the Blodgett tract.
Railroad grades include the Kerry Mainline and numerous spurs. These grades can be classified as:
a. completely destroyed, only
archival references
b. converted to roads
c. still visible with ties removed
d. visible with ties in place
a. Horseshoe Camp is identified as a site by the USGS. It was occupied for many years while this area was logged and the railroad operated.
No Native American sites have been recorded between the Columbia River and Nehalem drainage and only a few sites have been recorded on each of these drainages. The low number of sites recorded may be a function of the small number of surveys that have been conducted in this part of the state to identify cultural resources.
The likely areas for Indian sites at the Blodgett Tract are those areas with slopes less than 5%, because people usually prefer camping on level ground, and within one quarter of a mile from water (see Figure 5.). Other factors, such as the concentration of resources, are unknown at this time but also would have influenced site location. According to this model, Horseshoe Camp may have a prehistoric component, however predictive models are poor tools in archaeology because human behavior is difficult to include.
Approximately 240 acres of the tract has been surveyed for cultural resources.
Figure 4. Predictive map for cultural resources.
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