The Forest Health Technology Enterprise Team - Fort Collins, Colorado (FHTET-FC) provides
remote sensing and image analysis expertise and services in the detection, monitoring, and
evaluation of forest health-related concerns. Services are provided on a cost-reimbursable
basis to USDA Forest Service units, other federal agencies, and state entities.
The FHTET-FC remote sensing and image analysis services are focused on three areas:
Sensor Evaluation and Development
The evaluation of new sensor technologies includes airborne
and spaceborne sensors; analog and digital sensors; and panchromatic,
multispectral, and hyperspectral sensors. Spectral technologies
include visible, infrared, and radar. Also included is the
evaluation and development of image analysis techniques to
process acquired images and derive useful products. Recently
developed technologies to acquire imagery of pest outbreaks
include the airborne video toolkit and digcam software. These technologies are utilized in mapping potential forest health problems and providing data for risk assessments.
Aerial Imagery Acquisition and Image Processing
Aerial imagery acquisition is designed to provide high quality imagery to support forest health analysis and monitoring. FHTET-FC operates a Beechcraft King Air 100A aircraft, which is equipped with a 20-inch optical window camera port for use with a large-format film camera (9x9). A service ceiling of 23,000 feet above mean sea level allows for the collection of photography up to 1:30,000 scale. GPS is utilized for flight line navigation. Additionally, an automated position and orientation unit allows for near-realtime automated georeferencing of acquired digital imagery. Services include mission planning, preparation of flight maps, acquisition of imagery, purchasing and processing of film, index map(s) of imagery coverage, and delivery of end products (film, photos, digital images) to the end-user.
After the first full season of image acquisition using the Applanix POS system FHTET performed a test to evaluate image accuracy. Randomly sampled points on FHTET orthophotos were compared with the equivalent locations on USFS orthophoto quads and National Agriculture Imagery Program (NAIP) imagery. All points tested met the USGS National Map Accuracy Standards (NMAS). This accuracy assessment was first published by the American Society of Photogrammetry and Remote Sensing (ASPRS) as a paper presented at the Eleventh Forest Service Remote Sensing Applications Conference, April 24-28, 2006.
Remote Sensing training and Technical Support
training courses have been developed specifically for Forest Health Protection and Remote Sensing. This training is provided through the USDA Forest Service - Remote Sensing Applications Center (RSAC) in Salt Lake City. FHTET-FC maintains a remote sensing lab to provide a work area, photogrammetric equipment, GIS (Arc/Info), and Image Processing capabilities. Digital processing of imagery can be provided utilizing an IBM 6000 43P-240 workstation with Erdas Imagine 8.4 software. Technical support for image processing digital and analog video imagery is available. FHTET-FC can perform the photo interpretation/image analysis for small projects on a cost-reimbursable basis
FHTET-FC equipment includes the following:
- Aerial Photography
FHTET maintains two mapping camera systems: a Zeiss RMK A 21/23 mapping camera (9x9 inch fi lm format) with an 8.25-inch focal length lens and a Zeiss RMK A 15/23 mapping camera with a 6-inch focal length lens. Collected photos can be scanned for digital applications. Aerial photography is best suited to mapping activities such as larger block coverage or sample blocks.
- Positioning and Orientation System
The Applanix POS AV 310 system is a combination of a high-speed GPS unit, 3-axis gyroscope, and accelerometer. The system is mounted onto the camera system and the collected measurements are processed to achieve a position and orientation solution that can be utilized by image processing software to accurately georeference the imagery collected during the mission.
- Digital Color Infrared Camera
A Kodak Proback 645 camera produces 16-megapixel color infrared images. These images are post-processed in 24-bit TIFF format, which can be orthorectifi ed using the Applanix data using a technique known as “automated aerial triangulation”. The types of imagery coverage that can be acquired are: block area (wall-to-wall coverage), sample points/ground plots, and sample strips/transects. However, due to the small footprint, such imagery is recommended for small project areas.
- Epson 1640 XL Medium format scanner
This scanner will scan 9x9 photos and transparencies (negatives/positives) at resolutions up to 1600 dpi. Though not photogrametric quality, the resultant image is usable for most vegetation mapping needs.
Mission Cost Estimates and Procedures:
Due to the specifi c needs of individual missions, it is diffi cult to provide cost fi gures by line-mile, square-mile: costs vary greatly by scale/ground sample, imagery type, size and confi guration of the project area, ferry time, and other factors. The best planning procedure involves providing a map outline of the area(s) to be imaged and mission specifications. Electronic ArcView shapefiles are preferred; however, paper maps can be sent by either mail or facsimile. If mission specifications are unknown, the team can provide consultation on mission designs. A cost estimate will be prepared and sent to the customer. As a federal unit, all costs associated with the imagery acquisition are chargeable to the benefiting function (charged-as-worked), just as any savings are passed on to the benefiting function. Once the customer agrees on cost and mission parameters, funds are transferred via an In-Service Agreement (ISA FS-6500-46). As much as possible, requests will be handled on a “fi rst-come, fi rst-served” basis.
As with most imagery acquisition projects, the delivery timeframe is dictated by weather conditions. Scheduling of services is balanced by customer needs and prevailing weather conditions. Once imagery is collected, film is sent overnight for processing. Scanning and printing are dependent upon thirdparty schedules. Small projects can be completed in 1 to 2 weeks after actual imagery acquisition.