Treesearch

Experts from relevant disciplines exchanged information on three important problems of pesticide spray technology. The four papers presented are Physical Parameters Relating to Pesticide Applications by N. B. Akesson and W. E. Yates; The Micrometeorology and Physics of Spray Particle Behavior by H. E. Cramer and D. G. Boyle; Impaction of Zectran Particles on Spruce Budnomi Larvae: A Field Experiment by J. W. Barry and Others; and Assessment of Insecticide Spray Processes by C. M. Himel. Summaries of the three workshop sessions are also included.

Use of the chlorinated hydrocarbon insecticide lindane to control bark beetles is controversial. Differences of opinion persist, even among knowledgeable entomologists, on whether use is justified in view of potentially harmful side effects. Effectiveness of lindane treatments, as employed in preventing tree mortality from bark beetles, is also in question. In seven papers, relevant information from many sources is reviewed by investigators who hold divergent views. The papers present data on the biological characteristics of lindane, its persistence in the environment and effects on both...

Pitch pine seedlins were grown at constant temperature and photoperiod. Net CO2-uptake h-1 g-1 leaves decreased stadily during ontogeny until leaf production ceased. Thereafter, there was no change or a slight increase. Though the 0ntogeneic pattern was the same in populations native to different geographic areas, there were differences among populations in the rate of CO2-uptake. Root respiration, calculated from the difference between CO2-uptake and net assimilation rate, accounted for 6 to 69 per cent of diurnal assimilation.

Data products from the Skylab Earth Resources Experiment Package were examined monocularly or stereoscopically using a variety of magnifying interpretation devices. Land use, forest types, physiographic sites, and plant communities, as well as forest stress, were interpreted and mapped at sites in Georgia, South Dakota, and Colorado. Microdensitometric techniques and computer-assisted data analysis and sampling procedures were developed and tested against ground truth. Results indicate that only Skylab S190B color photographs are good for classification of forest and nonforest land (90 to...

Attitudes and characteristics of campers reached by two Federal campsite reservation programs in experimental use during the summer of 1973 were surveyed. Most campers strongly favored reservations, but preferred that one company sell reservations to all government campgrounds. Questionnaire responses indicated need for a systematic procedure for referring campers to vacant campsites, along with a more effective program of information on the reservation systems. A majority of campers were satisfied to get their first choice of campground, but a few also wanted freedom to choose their...

The performance of 90 species, mostly from the tropics and subtropics, was appraised in field trials for 5 years. Planting sites ranged from near sea level to 6360 feet (1940 m) elevation; rainfall from less than 20 inches to more than 200 inches (500 to 5000 mm); and soils from thin mucks overlaying lava rock to deep, highly leached latosols. Thirty-two hardwoods and 10 conifers were rated as promising for either timber production, watershed production, erosion control, or amenity plantings. Fourteen are native to Australia, and are eucalypts. Few of the high quality timber species tested...

Maps for wildland resource inventory and managament purposes typically show vegetation types, soils, and other areal information. For field work, maps must be large-scale. For safekeeping and compact storage, however, they can be reduced onto film, ready to be enlarged on demand by office viewers. By meeting certain simple requirements, film images are potential input to computer-mapping systems.

Range RAM (Resource Allocation Method) is a computerized planning method designed to assist range managers in developing and selecting alternatives in spatial and temporal allocation of resources. The technique is applicable at the frest or district management levels, or their equivalents. Range RAM can help formulate plans that maximize the production of range outputs, net revenue, or that minimize the cost of management while meeting a variety of constraints on range productivity, budget level, and economic returns. Constraints are specified by expected budget levels and aggregate output...

Large-scale aerial color photographs were used to evaluate trout habitat by studying stream and streambank conditions. Ninety-two percent of these conditions could be identified correctly on the color photographs. Color photographs taken 1 year apart showed that rehabilitation efforts resulted in stream vegetation changes. Water depth was correlated with film density: 76.4 percent on normal color film and 73.5 percent on infrared film. Shadow-length measurements of streambank vegetation height were 86 percent accurate. A technique to measure the degree of shade created by streambank...