Introduction
During the past several years many researchers have noticed a decline in blue oak (Q. douglasii) seedling survival rate. It has been debated whether this low survival rate is caused by the inability of the seedlings to become established. Some field experimentation suggests that seedlings are damaged by rodents or other small herbivores. There is conflicting information about the affect of grazing livestock on seedling survival.
Research has been done as to the effectiveness of tree shelters, weed control and protection from grazing livestock. This study is an attempt to utilize the best of several well established methods of protecting the blue oak seedlings.
The objective of this study is to determine the effectiveness of various methods of protecting blue oak seedlings. The use of tree shelter schemes and weed control will be mixed in a variety of ways in an attempt to be selective for the particular group of animals that may be causing the perceived problem.
Participants
The participant researchers in this field study are volunteer seventh and eighth grade students from Springville Elementary School. This field study was conceived, designed and carried out by these students. Organization and analysis of the data collected has been by students. Guidance and supervision has been provided by the Springville School Science Teacher, the Circle J-Norris Ranch Educational Coordinator, and a variety of Springville Elementary School parents.
Materials and Methods
Time Span: March, 2001 to present time (May, 2007)
Status: Ongoing
Location: Central California, Sierra Nevada foothill oak woodland; 600 m elevation
Site: Circle J - Norris Ranch; North of Springville, California; 380 hectaresExperimental Design: 5 Groups of 1 to 4 seedlings per group, at varied locations within study area
Treatments:
1. C --control; no weed control or tree shelters
2. WC --barrier cloth weed control
3. PS --0.91 m high plastic shelter
4. MS --1.2 m high wire mesh shelter
5. All --then combination of WC, PS, and MS