Dieback of a 30-year-old Douglas-fir plantation in the Brittain River Valley,British Columbia: Symptoms and diagnosis

Severe dieback and disorted growth was observed in a 30-year old plantation of coastal Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco, var. mensiesii] growing in the Brittain River Valley in southwestern coastal British Columbia. Shoot, bud and tip dieback, bushy multileadered crowns, enlarged and darkened pith and red to brown discoloration on leading shoots as well as bronzed, necrotic and chlorotic foliage were found to be common features of this plantation.Boron deficiency has been diagnosed as the cause of dieback and distorted growth. Foliar samples from affected trees averaged only 6 ppm boron, well below critical minimum levels of 8–12 ppm reported in the literature for a number of coniferous trees. The average boron concentration in the foliage of unaffected trees growing on upper slopes in the same valley was 14.5 ppm. The site characteristics of the affected plantations were found to be similar to those described by other workers as likely to result in soils low in total boron. A complete nutritional diagnosis carried out on all foliage samples collected also suggested sulphur and magnesium deficiences.     

ON THE EFFECTS OF INHALATION OF THE FUMES OF ÆTHER ON DOGS AND CATS, AND, BY INFERENCE, ON THE HORSE; WITH THE PROBABLE UTILITY OF SUCH IN VETERINARY MEDICINE

When the great American discovery was first announced, every veterinarian must have speculated upon the applicability of the process to the lower animals. Doubtless many experiments have been made by various parties, and I have tried the setherial fumes on both dogs and cats. I placed the sulphuric aether in a Florence flask, to the neck of which a large bladder was secured. The head of the animal was then introduced into the bladder, and a spirit lamp applied to the flask. This answered very well; but Mr. Lucas has attained every result with a more simple and less fragile apparatus.     

Fungicidal activity of substituted quinoxalines

Twenty substituted quinoxalines based on the structure of 6 (or 7)-methyl-3-phenyl-1, 2-dihydroquinoxalin-2-one, a fungicidally active photodegradation product of quinomethionate, were synthesised. Eleven of these compounds had ED₅₀ values, as protectant sprays against Podosphaera leucotricha, of 0.1 mmol or less; these compounds had an aromatic substituent at the 3-position of the quinoxaline ring. They were less active as protectant leaf dips against Erysiphe graminis f. sp. hordei than against Podosphaera leucotricha; none showed any systemic activity as a soil-applied treatment against Podosphaera leucotricha. One compound was more active than quinomethionate as an eradicant spray. In spore germination tests on fungi from different taxonomic groups, the quinoxaline derivatives were active against only one basidiomycete (Uromyces fabae), whereas quinomethionate showed a broad spectrum of activity. The possible significance of this difference in spectrum of activity with respect to the mode of action is discussed.     

Liquid chromatographic determination of bendiocarb in technical materials and wettable powder formulations: collaborative study

A liquid chromatographic method for determination of bendiocarb in technical materials and wettable powders was tested by 12 collaborators. Bendiocarb is dissolved in acetonitrile containing 0.1% propiophenone as internal standard. This solution is analyzed on a liquid chromatograph utilizing a reverse phase (C18) column. The compound is detected at 254 nm and peak area is used for quantitation. The 3 different materials studied contained 20, 80, and nominally 100% bendiocarb. Each was examined in duplicate to provide the necessary matched pairs. Collaborators approved of the ease and simplicity of the method and, in particular, the way the method can be applied to automatic injection assemblies. The statistical data show acceptable precision of the method: Reproducibility coefficients of variation were 20% material, 2.04%; 80% material, 1.02%; and nominal 100% material (technical product), 0.64%. The method has been adopted official first action.     

Near-future sea level impacts on coastal dune landscapes

Very little attention has been paid to the impact of global warming, especially sea level rise, on coastal dunescapes, despite the fact that these provide natural protection along many of the world's shorelines. This paper reviews likely responses given the IPCC climate change predictions to 2030AD, which include sea level rise in the order of 0.09 to 0.29m. It is envisaged that coastal dunes will react in a variety of ways dependent both on regional and local factors. Rising water levels will increase susceptibility to erosion, but the fate of released sediment, particularly the onshore/offshore partitioning, must depend on morphodynamic antecedence, and the propensity for periodic domain shifts. The release of material at the shoreline may allow construction of coastal dunes, to the point of progradation in some zones. The response of dune vegetation to a warmer, wetter climate is uncertain. Most of the main temperate dune species are C3 plants which given favourable conditions would respond positively to CO₂ enhancement. However local factors may offset such potential gains.