Treesearch

An Aerial survey using an operation recorder was made over a remote forested area of the Sierra Nevada, in central California. Data on insect-caused mortality were gathered. The survey saved several man-weeks of costly ground work that would have otherwise been required to obtain this information. The technique used proved to be an efficient and inexpensive way of collecting data for forest management decisions.

After 5 years, 4 of 14 fungicides tested showed varying pr of development into satisfactory direct control of blister rust. Little promise of systemic control was found. Trees treated were second-growth sugar pine in a mixed conifer forest in eastern Shasta County, California, where blister rust has been intensifying for many years. Most trees received basal-stem treatment. Tree mortality after treatment--from all causes other than obvious accidents --varied from zero to 60 percent. No antifungal antibiotics were included in these tests.

Among several fungicides tested, Phytoactin L-340 and Dowicide 1 (o-phenylphenol) showed the most promise for systemic chemical control of blister rust on sugar pine in northern California. The trials included 22 tests on 224 sugar pines: five with Acti-dione BR (cycloheximide), one each with five common chemical fungicides,and 12 with phytoactin. Apparent effectiveness of the antibiotics rose to marked maximums 2 to 3 years after application, then declined.

Since 1963, there have been 17 slash disposal burns carried out successfully in pine patch-cuttings on the Challenge Experimental Forest, Yuba County, California. The burned units ranged from 2 to 46 acres. Costs per acre ranged from $8.42 to $60.97. Answers to questions most asked by foresters about broadcast burning pine slash are given in the form of a dialogue.

ABSTRACT:Combinations of three annual broadcast and individual plant spray applications of brushkiller (a 50-50 mixture of 2,4-dichloro- and 2,4,5-trichlorophenoxyacetic acid) in water-oil emulsion were compared to find the most effective, economical sequence of treatments to kill sprouting scrub oak (Quercus dumosa Nutt.) plants. No one treatment combination had a clearcut advantage. Regardless of treatment combination, three successive applications were needed to obtain satisfactory control.

To assess effectiveness of fire hazard inspection procedures in securing compliance with fire safety requirements, effects of different types and combinations of contacts and timing were determined, and the production capacity of inspectors measured. It was demonstrated that fire law inspection is as much fire prevention education and engineering as it is law enforcement. The public was found to be uninformed about fire laws but was very receptive to an inspection program.

Chaparral-as the term is used in California-refers to dense stands of evergreen, shrubby vegetation. The information in this handbook applies to the chaparral within the brushland zone that lies below the State's commercial timber belt (fig. 1). This zone includes about 11 million acres of chaparral and associated types and 9 million acres of woodland types.

Effectiveness of hazard control was evaluated by analyzing data on tree failures, accidents, and control costs on California recreation sites. Results indicate that reduction of limb hazard in oaks and bole hazard in conifers is the most effective form of control. Least effective is limb hazard reduction in conifers. After hazard control goals or control budgets have been set the optimum allocation of funds and efforts can be determined.

Moisture measurements were made in three media?paraffin, water, saturated sand?with four neutron miusture meters, each containing 226-radium-beryllium, 227-actinium-beryllium, 238-plutonium-beryllium, or 241-americium-beryllium neutron sources. Variability in surface detection by the different sources may be due to differences in neutron sources, in length of source, or both.

Diluted pollens would have many uses by the tree breeder. Dilutions would be particularly advantageous in making many controlled pollinations with a limited amount of pollen. They also would be useful in artificial mass pollinations of orchards or single trees. Diluted pollens might help overcome troublesome genetic barriers to crossing. Feasibility o,f using diluted pollens is being studied at the Institute of Forest Genetics at Placerville, California, in an effort to develop improved procedures of hybridizing pines.