Showing papers by "Forest Research Institute published in 1974"

Insect damage to plantation‐grown eucalypts in north coastal new south wales, with particular reference to christmas beetles (coleoptera: scarabaeidae)

Abstract: The Christmas beetles Anoplognathus chloropyrus and A. porosus feed on the leaves of eucalypts, particularly E. grandis, in plantations established for wood pulp production. A. chloropyrus is highly gregarious, causes more damage than does A. porosus, and tends to be present in high numbers in alternate years. Because of the timing of the insects’ life cycles, and their feeding preferences, defoliation levels below about 50 % are unlikely to reduce the rate of tree growth. Severe defoliation is limited to young trees planted on old grasslands which provide a favoured breeding place for the insects. Possible methods of minimizing damage by A. chloropyrus are discussed.

The use of peroxidase activity for monitoring and mapping air pollution areas1

Abstract: Peroxidase activity (p. a.) of several tree species was investigated in a forest influenced by F-containing exhalates of an aluminium smelter. P. a. increases with age of tissue, particularly under the influence of fluorides. It was used therefore to map the zone of plant reaction in apricot orchards in the vicinity of an aluminium smelter and it supplements foliar analysis. P. a. in foliage of white ash was used to determine whether exhaust of automotive traffic in the city of Zurich does affect vegetation. A significant increase of p. a. was found in the city although the plants did not show any symptoms of injury. P. a. thus is a very sensitive indicator of plant reaction to air pollutants and allows to detect “hidden” injury (no visible symptoms).

Chinone als Wehrsubstanzen bei Einigen Orientalische Macrotermitinen

Abstract: Sechs Macrotermitinenarten aus der GattungenMicrotermes, Macrotermes, Odontotermes undHypotermes werden auf das Vorhandensein von Wehrsekreten untersucht. Die Soldaten von funf Arten geben beim Kampf aus ihren grosen Labialdrusen Wehrflussigkeit ab. BeiMacrotermes gilvus-Soldaten, die sehr kleine Labialdrusen besitzen, last sich keine Sekretabgabe beobachten. Bei allen vier Gattungen finden sich Arten, deren Sekret Chinone enthalt. Diese Verbindungen fehlen beiMacrotermes gilvus undOdontotermes horni. Im Sekret vonOdontotermes, Microtermes undHypotermes sind zuzatzlich Klebstoffe enthalten.

The use of a radioactive tracer to study the nesting system ofMastotermes darwiniensis Froggatt

Abstract: A new method for the tracing of termite nesting systems is proposed and proved in field trials withMastotermes darwiniensis nesting systems. An attractive bait containing γ-ray emitting scandium-46 oxide is inserted into an infested site. The bait is eaten rapidly and taken to the nests where trophallactic transfer spreads the scandium through the colony members. The scandium is finally excreted and the excreta fixed in the gallery walls and carton of all subcentres which can then be found using a γ-ray detector. The use of other radionuclides as colloids in similar bait is described. This new method appears to introduce a new concept into the tracing of social insects.

Variation of N, P, K, Ca, Mg, Mn, Zn, and al in slash pine foliage

Abstract: The seasonal patterns of foliage nutrient concentrations and contents were monitored for two growing seasons in an 11‐year—old Pinus el1iottii stand. In the first growing season after needle initiation, N, P, K, Mg, and Zn concentrations decreased, but this was followed by an increase in the fall and winter months. Another drop in concentration of all elements, except P, occurred in the second growing season. Decreases in total contents indicated that this drop was a result of translocation to other tissues. In contrast to the mobile elements, the concentration and fascicle contents of Ca, Mn, and Al increased with aging of the needles. Between‐tree variability was least for N, P, and Zn and the N, K, Mg, Mn, and Zn in the current foliage had consistently lower variation than that in the 1‐year‐old foliage. Between‐tree variation for K was lower in the winter than the spring. For pine foliage, recommended sampling period for N, P, Mg, and Zn is mid to late summer and for the other elements it is ...

Abstracts Of Contributed Papers — National Plant Pathology Conference, Sydney, May 1974

Abstract: Effect of Soil Moisture on Decline of Pinus radiata

Observations on the growth rate inMartesia striata (Linn.), the wood-boring pholad in the cochin harbour region on the south-west coast of India

Abstract: Experimental studies conducted in Cochin harbour during 1967 to 1969 have shown thatMartesia striata settled on timber test panels during the months December to May when the salinity of water varied from 28·2‰ to 34·0‰ and temperature from 29·4° C to 32·5° C. The maximum size of the animals in one month old panels varied from 2·0 mm to 6·0 mm. The rate of growth in the second, third and fourth months varied from 6·0 mm to 16·0 mm; 4·0 mm to 19·0 mm; and 1·0 mm to 7·0 mm, respectively. The average growth rates calculated for the second, third and fourth months showed that the growth was rapid in the second and third months with the maximum in the third month. No definite correlation between the rate of growth and the hydrographic conditions was perceptible. The pattern of growth in the species was found to follow Bertalanffy’s equation. The length-height relationship during the course of growth inMartesia striata showed that in early stages up to 3 mm size, the length of the animal was equal to its height and as growth progressed the rate of increase in height gradually diminished and in large specimens the height measured only about half the length of the animal.