Record Details
Field | Value |
---|---|
Title | Aerial photographs as an aid in preparing a management plan for the Blodgett tract |
Names |
Voorhies, Ray Van
(creator) Dilworth, J. R. (advisor) |
Date Issued | 1952-05-13 (iso8601) |
Note | Graduation date: 1952 |
Abstract | There are approximately 4,000,000 acres of cut-over and burned-over land in western Washington and Oregon which are either non-stocked or unsatisfactorily stocked with young forest growth. This brings about a great need for a quick and efficient method of land examination from which to plan reforestation measures and make up management plans. This thesis is an explanation of one method, that of using aerial photographs in conjunction with limited ground observation. An example is given which illustrates that each $l.00 saved in the planning stage of forest regeneration means $l9.23 more profit at the end of 100 years using an interest rate of 3% compounded annually. More and more forest industries are beginning to use aerial photos for management plans, reforestation programs, and even cutting plans and preliminary road location. The first part of this thesis deals with the using of the aerial photographs and the recognition of the information found on them as substantiated by ground examination. The Blodgett tract is 2400 acres of logged and burned-over land in northwestern Oregon which was deeded to the Oregon State College School of Forestry for the purpose of establishing a reforestation study area. The photographs used were standard 9 x 9 inch contact prints of negative photographed with a f-l2" Aerial Mapping Camera by Delano Aerial Surveys of Portland, Oregon. The average scale of photography was 1:12,000. The photographs were taken to the Blodgett tract and used as a guide in examining certain areas of the tract. Next a base map was made of the area using a slotted template laydown for horizontal control. The planimetry was transferred to the base map from the aerial photos by means of a multiscope. Fuel types were also determined from the photos. Other maps, including the proposed road and water development map, the hour control map and the seen area map, were also prepared. They were not particularly dependent upon the photographs for their information, except that the roads were located along old railroad grades and the water holes were beaver ponds, both of which could be observed on the photographs. A second land examination was made to correlate the types of vegetation on representative areas with the vegetational types given those areas from aerial photograph interpretation. Certain changes were made where the land examination showed the stocking or the species composition to differ from the photo interpretation. Well defined areas of each type were examined by the stocked quadrat method of reproduction examination and final classifications were based on the results. In conclusion to the first part of the thesis the author states that the field work in preparing a reforestation plan can be reduced to one-fifth of the time required by land examination alone. Forest boundaries and type boundaries may be easily recognized on the photographs and transferred to the base map. Fuel type and hour control maps may be made from the photos. Seen area maps may not be made from photographs without first constructing a topographic map. Tree species can be recognized to a certain degree from the photographs. Pure fir stands can be differentiated from pure hemlock stands, but they are not easily separated when in a mixture. Alder stands can be separated from the willow-vine maple stands, but again not in mixtures. However it is easy to distinguish coniferous stands from the hardwoods. The degree of stocking on reforestated areas can be determined from aerial photo examination, but only when the young trees average better than five feet in height and two feet in crown diameter. Part Two of the thesis is a brief management plan for the Blodgett tract. It includes the history, physiographic features, and condition of the forest on the tract. Silivicultural recommendations are made and also the fire protection maps previously mentioned. The area has high site quality, ample moisture, deep soil, and is ideally suited to the growing of Douglas-fir veneer stock on a rotation of between 100 and 150 years. It is located close to the Columbia River, which facilitates the transportation of the timber products. There is an adequate supply of local labor. The author recommends the planting of non-stocked and understocked areas, the pruning of selected crop tress, and periodic thinnings. Also recommended is the construction of access and fire roads, and a program of rodent and game control to assist in the re-establishment of the forest. |
Genre | Thesis/Dissertation |
Topic | Reforestation |
Identifier | http://hdl.handle.net/1957/12971 |