Forestry Monitoring
Public Summary of Research & Monitoring Activities
The following summaries are related to activities performed on site to monitor and restore ecosystem function in areas with little anthropogenic activity or in agriculture areas where BMPs have been implemented. For further information, please see additional research publications related to Swanton Pacific Ranch on Cal Poly Digital Commons.
Little Creek Water Quality Monitoring and Channel Change
The Swanton Pacific Ranch watershed project is designed to evaluate the effectiveness of timber harvesting practices, afforded through the California Forest Practice Rules, to protect water quality from increases in sediment yields. Monitoring activities provide scientific documentation of water quality (suspended sediment concentration, turbidity, and temperature) and channel conditions (longitudinal profile, cross section, roads, landslides, and streambank sediment sources) before, during, and after single-tree and small group selection harvests and more recently, following wildfire. Data collected from paired and nested watershed study design will be used to evaluate the effectiveness of harvest practices.
Precipitation and Sediment Source Survey
Three rated-section flumes on Little Creek (Main Stem, North Fork, and South Fork) confine the channel between two sidewalls and maintain a natural channel bottom with a concrete sill for grade control. A forth natural channel monitoring site was established in the upper North Fork in 2001. At these locations, stage, turbidity, temperature, and event-based water samples are collected. During a significant hydrologic event, water samples are removed from each site at one hour intervals using ISCO 6700 automated water quality samplers. Instream water is monitored at 15-minute intervals using instream turbidimeter and temperature probes. Water samples are analyzed for turbidity and suspended sediment concentration at an on-site water lab. Seven years of calibration data (2001-2008) have been collected at the four main stem monitoring sites. Event-based suspended sediment load analysis indicates a stronger relationship for the nested component of the study, based on 5 years of calibration data. Suspended sediment load values for all events after the harvest would need to increase by approximately 30% to be statistically detectable using the nested study, while the paired study was found to be far less statistically significant. Precipitation measures from storm events related to streamflow variation are monitored at seven locations in the Little Creek subwatershed, from the ridgeline to the confluence with Scotts Creek. A tipping bucket recording raingage and a non-recording Clear-Vu raingage record data for comparing rainfall totals that measure to the nearest 1/100th inch.
Geomorphic Monitoring and Light Detection and Ranging Survey
The long-term water quality study is complimented by geomorphic monitoring and analyses. The goal of geomorphic monitoring is to better understand the physical conditions of the Little Creek subwatershed and the role of natural and human-influences. Surveys produce visual representation for changes in slope and allow for quantitative comparisons to statistically evaluate change. These measurements can aid in the interpretation of suspended sediment yields over time. In 2002, eroding streambanks, stream-side landslides, and other potentially unstable bank characteristics were identified and quantified along Little Creek. Annual monitoring and geomorphic analyses include collection of longitudinal profile surveys, cross section surveys, roads and landslide inventories, stream bank sediment source and channel stability surveys. On-the-ground surveys capture the change in geomorphic characteristics of the channel, such as terraces, channel capacity, bankfull, and thalweg location. Longitudinal profiles and permanent channel cross section surveys describe existing morphologic conditions and are to be used to identify areas of sediment sources or sinks and to evaluate channel changes over time. Seventy permanent cross-sections represent dynamically aggrading and degrading areas. Data from both the eroding features and the measurements of channel characteristics are analyzed for potential correlation and will serve as baseline conditions for future assessments.
Studies are also underway to determine the extent to which remote technology can identify and quantify traditional watershed and channel characteristics. Airborne Light Detection and Ranging (LiDAR) data was collected in Spring 2003 and 2008 to determine its ability to aid in the measurement of channel characteristics. Combining an aircraft-mounted laser with GPS positioning and orientation measurements, a range of distances to the targets below are translated into high resolution digital elevation models. LiDAR terrain data has also been used in mapping historic landslides that have shaped the watershed as it appears today. These data may support on the ground surveys to identify and evaluate conditions of roads and landslides, streambank sediment sources and channel stability. LiDAR has also been used successfully to describe road position in densely forested mountainous terrain (Master thesis to be completed by Russell White, Dept. of Natural Resource Management).
Continuous Forest Inventory (C.F.I.) - A Long Term Forest Monitoring Project
C.F.I. plots are part of long term forest monitoring program on the lands of Cal Poly's Swanton Pacific Ranch that monitor forest conditions over time. Approximately two hundred, 1/5 acre fixed plots are spaced out in a systematic random sampling system over forested areas that results in a 2-3% sample size. Plot measurement began in 1997 and re-measurement occurs every 10 years.
Information taken at each of these plots consists of: plot number, slope, aspect, declination, date, crew, number in crew, plot notes, regeneration tally, tree and snag inventory, species, witness trees, distance and bearing to each tree in the plot, diameter at breast height (DBH) to a .10 inches, height, crown class, height to crown base (HTCB), damage and disease, breast height age, radial growth, plot photos, plot comments, Herbaceous Vegetative Groundcover (consists of species identification and % occupation), student use difficulty, and Poison Oak Level (P.O. level).
The main purpose of this intensive monitoring system is to help us determine what the sustainable levels of harvest are in the forest and how our selective harvesting practices affect the different vegetative communities over time.
To see how this information has been utilized please see the documents section to view the sustainability analysis in our, State approved, Non-industrial Timber Management Plans.
Pitch Canker Research and Monitoring
Pitch canker affects growth, vigor, and competitive status of Monterey pine with bole and top kill infection showing the most impact, however its progress and long-term impact remain unknown. Impacts of this disease have affected economies throughout the world market. Given the high public interest and concern over the spread of pitch canker and the decline of the Monterey pine forest, there remains a strong need for science-based forest management guidelines for the Monterey pine forests in California. Endemic Monterey pine (Pinus radiata D. Don) stands have been monitored at Ano Nuevo, Scotts Creek and one plantation stand containing individuals from Chile, Australia and New Zealand, surrounded by infestation. Over a decade of research and monitoring efforts at these sites have yielded valuable research findings, IMPACT an international collaboration project involving New Zealand, Australia, and Chile, five completed master's theses, and ongoing research by masters candidates and students of the Forest Health and Silviculture class in the Natural Resource Management department at Cal Poly San Luis Obispo's College of Agriculture. The foremost research and monitoring objectives are to establish and maintain stand structures that ensure a sustainable presence of the species.
Assessment of stand structure and species composition, tree growth, and Pitch canker infestation was performed (Piirto and Valkonen, 2005) using data from a representative sample of intensively measured temporary plots in the Scotts Creek stand where a continuous forest inventory (CFI) was conducted in 1999. Data from CFI plots assigned to the Monterey pine aggregation constituted a wide range of variation in stand density, species composition and tree diameters. Samples taken of Monterey Pine, Douglas-fir, and coast live oak include increment borer and stand structure (diameter at breast height (d), species, bearing (dir) and distance (s) from plot, species composition, spatial structure). The presence of damage, disease and severity of pitch canker and diseases other than pitch canker infection were recorded. Conifer regeneration, crown coverage, percentage of small broadleaves and understory vegetation was assessed. Conifers were additionally measured for height (h), crown class (dominant, co-dominant, intermediate, or suppressed), and height to crown base. Initial findings showed seedlings and saplings were less often infected than large trees and the major threats to Monterey Pine sustainability was intensive shading and competition from high stand densities of shade-tolerant broadleaf trees inhibiting regeneration, and growth of seedlings and saplings. Monitoring at the Scotts Creek stand continued for 5 years with a 10% sample of natives.
It remains unknown whether the primary cause is low seed rain in the absence of fire, poor seedbeds, or high stand density. Long-term monitoring remains in progress. Students from the Forest Health and Silviculture classes have been conducting pitch canker data collection on the plantation for the last four years. They sample the entire Ano Nuevo stand on an annual basis and are looking to develop resistance in a nursery trial in future work. Students continue to conduct inoculation and epidemiology studies in the Scotts Creek and plantation stands. The last collection of samples from the plantation was in November 2009 with 5 out of 5 positives for pitch canker. Inoculation trials for part of an epidemiology study were conducted in May 2009 and have grown resistance screened trees by micro-propagation in the San Luis Obispo lab.
Mill Creek Restoration & Monitoring
Mill Creek possesses high quality aquatic and terrestrial habitat that has been threatened by bank erosion and poor hydrologic performance at specific locations along the Mill Creek Road. This restoration project was designed to improve salmonid habitat for three federally and state listed endangered species; (the coho salmon, the Central California Coast ESU of steelhead, and the California red-legged frog) and hydrologic conditions, (reduced erosion and improved water quality), while offering additional protection for secure residential ingress/egress for Mill Creek road. The incorporation of constructed large wood features and instream features enhance lateral pool formation and provide terrestrial and aquatic refuge habitat, while protecting the streambank from erosion. Protection from sedimentation effects of suspended fines extend throughout the lower reaches of Mill Creek and further downstream along Scotts Creek. Physical, hydrological and biological monitoring of Mill Creek was conducted before, during and following phases of instream structure placement and vegetation restoration. The monitoring design was developed in reference to recommendations made by NRCS for riverine forest restoration projects. Some bi-annual monitoring measures are based upon similar restoration *recommendations from NOAA, designed to identify changes in channel morphology, stability and vegetative communities. Hydrologic monitoring documents the hydro-period and water source availability. Measures of physical state address "sediment grain size and topography/bathymetry" using as-built measurements for instream structures, as-built longitudinal profiles and pebble counts above and below instream structures. Biological monitoring records habitat created by plants as percent vegetative success for newly planted species around new structures and within the riparian zone. An initial photographic survey was made of the vegetative composition and structure ratios present at the site prior the start of construction and following each significant stormflow event during hydrologically-responsive periods using six permanent photo points established for each site.
Vegetation monitoring was performed immediately following project completion and repeated after each of the first rain seasons. The distribution of grasses, forbs, shrubs and trees present were noted. Bare ground was planted with native grasses and aquatic plants species collected and grown from local stock. Plant species selection was designed in an attempt to replicate the existing vegetation patterns, increase plant numbers, provide food and refuge habitat for wildlife and enhance channel and bank stability.
Floodplains were planted to replicate surrounding meadow-like vegetation and intermittent shrubs and trees. Channel banks were heavily planted with bunch grasses and additional shrubs along sloped banks to reduce erosion and create more preferred conditions of cover and temperature beneficial to native fish species. Revegetation activities continued for two weeks following construction, to establish plant varieties which support ecological function served by an array of structure types. Consistent replanting, watering and monitoring continued until the rainy season could ensure adequate soil moisture levels, after which seasonal monitoring has persisted for three annual rain seasons. Successful revegetation is based upon a desired increase of 50% coverage to be attained over a three year period and assessed through monitoring efforts. At the conclusion of the three year monitoring phase NRCS biologist will have the option of visiting the site to assess vegetation establishment.
Queseria Creek Restoration & Monitoring
This Queseria Creek restoration project was designed to reduce erosion and flooding in the watershed by improving the channel condition and reducing sediment delivery to Scotts Creek during flood periods. Queseria Creek provides refuge and spawning habitat for Coho salmon, steelhead trout and red-legged frogs. The project demonstrates techniques, carefully calculated placement of cross-vanes and j-hook structures within the stream channel that preserve channel slope and protect banks and the formation of pools and riffles which support salmonid life stages. Restored habitat components along ~1,600 feet of lower Queseria Creek include a meandering, gravel-lined streambed and native revegetation to support bank stability, provide forage, shelter and reproductive services for amphibian and fish species found within this riparian corridor. Improved hydrologic performance through the calculation of meander geometry and channel cross-sectional characteristics allows higher flows and sediment delivery to be retained within the channel while reducing energetic stress on the streambanks. Monitoring of stream channel, instream features, and native plant establishment is accomplished through consistent monitoring and adaptive management. Pearson recommended specific monitoring activities to be performed; biological (plant, wildlife and fish surveys) and physical characteristics (longitudinal profiles, cross sections and topographical surveys). These have been recorded through the use of photo-point monitoring at twenty-four permanent photo-points established to document stream realignment, channel construction, instream features and revegetation success.
Management responses have included prorogation and planting of native plant species, removal of dense plants and non-natives from the mid-channel. Plant species selected for revegetation mimic naturally occurring plant communities in the adjacent drainages, stabilize banks, and provide a diverse range of vegetative habitat for local fauna. Native, endemic plants were collected from within the Scotts Creek watershed as seed, seedling, or cutting in order to maintain the genetic integrity of the watershed. Additionally, eight juvenile Steelhead were tagged by NOAA fisheries biologists in the upper portion of the Queseria Creek and released into low flow pools. The locations of these individuals will be monitored to better understand movements within the creek. These improvements to fish passage and habitat may result in an increase of steelhead population and the use of the Queseria Creek drainage by Coho salmon as a refuge and spawning environment. Based upon data from photo monitoring and well water depth transects adaptive strategies were recently proposed (Casey, 2009) to reduce non-native recruitment, support instream vegetation to reduce hydrologic roughness and stabilize stream bank integrity, maintain a wetted channel for longer duration and create wind barriers to seed dispersal.
Queseria Creek restoration monitoring 2007 and 2009, respectively
Using dual frequency identification sonar (DIDSON) to monitor adult steelhead abundance in Scott Creek
This project is being conducted by NOAA Fisheries in collaboration with Swanton Pacific Ranch to aid in conservation efforts for steelhead and Coho salmon which spawn and are reared in Scotts Creek and many of its tributaries. DIDSON uses high frequency sonar (1.1 or 1.8 MHz) to produce near video-quality images in turbid water, which allows for detection and enumeration of fish, as well as estimation of fish size and swimming direction. Steelhead abundances are so low in central and southern California that a complete population census is needed through monitoring. Our interest in DIDSON stems from an absence of viable alternatives for monitoring steelhead run sizes under the field conditions typical of central and southern California streams. The objectives of the study include: validation of DIDSON produced counts using results from a fish weir located on the lower reach of Scotts Creek, (operated by Sean Hayes of NOAA Fisheries), evaluate data and steelhead behavior to produce an estimate of fish characteristics for final outlet escapement, and determine optimal site characteristics and management requirements for the DIDSON equipment during winter conditions.
