Treesearch

An Oak Tree Planting Project was conducted during 1989/90 in San Luis Obispo County by the Integrated Hardwood Range Management Program (IHRMP)/Central Coast. The local media and an IHRMP workshop were used to publicize the Planting Project and give information on the status of oaks (Quercus spp.) in California and oak planting techniques. Outreach efforts resulted in participation in the Oak Tree Planting Project by homeowners and ranchers as well as by 4-H, environmental, school, community, and homeowner-association groups: over 3,500 acorns were planted at about 1,200 sites (three...

Concern over oak woodlands has shifted away from ranch management towards residential areas. This shift has been accompanied by the involvement of decision makers who previously had little involvement with rangeland policies and practices. A survey of three recent Cooperative Extension workshops illustrates a number of important patterns regarding interest and activities of small landowners, landscape professionals, local government employees and concerned neighbors. The process of addressing these potential decision makers through existing professional or issue based interest groups...

We studied factors that restrict colonization of grassland by Quercus durata Jeps., an oak commonly found in chaparral on serpentine soils. The study site contained a chaparral/ grassland border that had been stable for at least 50 years. Monitoring of acorns planted in the chaparral understory and grassland revealed that, although initial seedling emergence was similar in the different sites, seedling survival was much higher in the chaparral. No seedling in the open grassland survived beyond the third year of the study, while 25 percent in the chaparral understory were still alive at the...

When a dam is struck by mud or debris flow, it is put under a great impact load and sometimes is destroyed. To prevent such destruction, it is important to perform basic research about the impact load on a dam due to debris flow. Thus, we have made an experimental study and tried to establish a method to estimate such a impact load on the dam. The experiment was performed with glass beads of 5mm in diameter as bulk solid, in an open channel which is 7m in length, and 15cm in both width and depth. In these experiments, the load on the dam was measured by a dam-type load measuring device,...

A field experiment was conducted to examine the effects of soil water availability on blue oak (Quercus douglasii) seedling establishment. Acorns were planted either into cleared plots of 0, 10, 20, or 40 cm diameter. The cleared plots were located in two grazed and one ungrazed site. Half of the plots received drip irrigation in a split plot design. Soil water and plot size, depending on the site, and initial acorn weight and parent tree all influenced oak seedling growth. Survival and height in subsequent growing seasons was dependent on early growth. Soil water availability in the first...

Historic background and the concept of slow-acting toxicants for population suppression of subterranean termites are reviewed. Information needed for development of bait-toxicants and studies needed to generate such information are summarized.

Baiting techniques have been developed over the years to control Coptotermes species, the most economically important termite species in Australia. Given the restrictions on organochlorines as termiticides in North America, this paper highlights research that has focussed on baiting programs against Coptotermes as alternatives to current control measures: drenching soil with pesticides or fumigation of entire structures. Details of the baiting procedures, toxins used, and their suitability for use in eradicating Coptotermes infestations in existing buildings are described. Suggestions are...

The benefits of direct colony baiting are described: bait substrates enclosed in polyvinyl chloride tubes are applied in direct contact with the galleries of the termite nest. Attention of researchers is drawn to the potential of this method for species other than the mound-building Coptotermes 1acteus. \t

Subterranean termites are important structural pests in much of North America, and worldwide. Recent studies of eastern subterranean termite (Reticulitermes flavipes [Kollar]) colonies in Ontario, Canada, indicate that these colonies contain greater foraging populations and forage over larger territories than was previously thought to be the case. These results are consistent with those obtained elsewhere with Coptotermes formosanus Shiraki and Heterotermes aureus (Snyder). Implications for the development of baiting techniques for termite control are discussed, and several laboratory...

Laboratory studies were conducted to determine factors that affect the tunneling behavior of the western subterranean termite (Reticulitermes hesperus Banks). Soil particle sizes between 2.36 and 0.84 mm prevented tunneling. Exposure to solid layers of calcium, magnesium, or zinc borate did not repel workers, but produced >87 percent kill within 10 d. No tunneling occurred in soils treated with the formulated termiticides tested at concentrations ≥50 ppm. Termites did not tunnel in soils treated with as little as 1 ppm bifenthrin or cypermethrin. Exposure to bifenthrin and cypermethrin...