Record Details
Field | Value |
---|---|
Title | Growth and replacement patterns occuring among selected dominant species associated with plant succession on Douglas fir clear-cuts |
Names |
Robinson, Myles Canby
(creator) Chilcote, W. W. (advisor) |
Date Issued | 1967-11-10 (iso8601) |
Note | Graduation date: 1968 |
Abstract | Growth and replacement patterns of four successionally important species occurring on Douglas fir clear-cuts were investigated from September 1964 to June 1967. The study was carried out on the Marys Peak watershed located near Corvallis, Oregon. Species used in the study include Holcus lanatus, Senecio jacobaea, Lotus crassifolius var. subglaber, and Berberis nervosa. During the summer of 1964,24 transects, each consisting of eight square-foot plots, were established on three separate clear-cuts. These 24 transects consisted of three replications of eight distinct types of vegetation, which include the above species in both pure and mixed stands. Each of the 24 transects was sampled 11 times over a three year period, to detect changes in vegetational structure and composition. In order to detect even slight changes in vegetation, a new sampling device was invented. This device employs the point frame principle, and may be used to sample vegetation up to four feet in height. The sampling device contains five pins which may be Iowered 25 times within a square-foot area. Tape measures are attached to each pin so that the height of each contact may be easily read. Results of the sampling show that, in general, the species studied grow better and more vigorously in mixed stands than in pure stands, and that competition does not appear to be an important factor in species replacement during the early stages of plant succession on Douglas fir clear-cuts in the watershed area. It is suggested that the behavior of a species on a young clear-cut is more dependent on its own ecology and changing soil factors than on competition from other species. It is further suggested that vegetation occurring on clear-cuts is usually not homogeneous in nature, but more often has a mosaic-like pattern, being made up of many smaller vegetational units which differ from each other in both structure and composition. It is recommended that much further study needs to be done on the ecology of successionally important species before plant succession of Douglas fir clear-cuts can be well understood. |
Genre | Thesis/Dissertation |
Topic | Cutover lands -- Oregon |
Identifier | http://hdl.handle.net/1957/46982 |