Grains and field crops
Effect of the leaf-mining moth, Dialectica scalariella, on development and seed production of Paterson's Curse, Echium plantagineum.
Location: Jane Brook (Swan Valley)
The aim of the trial was to reveal the effect of the leaf-mining moth on the growth and reproductive output of Paterson's curse. The trial was conducted at Jane Brook (Swan Valley), a site heavily infested with the moth.
Establishment and spread of the leaf-mining moth.
Location: Perth, Avon Valley, Northam, York, Chittering Shire.
The progress of winter 1989 releases of the leaf-mining moth was monitored by inspecting release sites in October 1989, when the moth was found at 35% of the 186 sites surveyed. A second survey in April 1990 found that that moth was still present at 22% of the 150 sites surveyed, mainly around Perth and in the Avon Valley.
The results showed that the leaf-mining moth achieved a regional distribution in 1990. The unusually wet summer of 1990 almost certainly aided the moth's survival and allowed numbers to increase.
Monitoring the leaf-mining moth and Paterson's course at Muresk
he leaf-mining moth was re-introduced to Muresk in June 1990 by transplanting heavily infested plants from Jane Brook (Swan Valley). A small population developed that caused a limited amount of leaf damage to plants growing within 1-2 m of the surviving transplants.
Persistence of matricaria (Pentzia globifera)
Although P. globifera has been prevented from producing seeds at the Barakee (Mukinbudin) study site since its last seeding episode in 1987, seedlings have emerged every year subsequently. In 1990, seedlings were first observed in late February and were the consequence of heavy rains early that month and in late January (total = 104 mm, Mukinbudin Post Office). This was much earlier than in previous years when germination occurred with the Autumn break-of-season.
Skeleton weed population structure and detectability.
The objective of the study was to determine the likely detection rate of an experimental air-borne sensor for skeleton weed. The sensor is potentially capable of detecting skeleton weed if the plant covers more than 10% of a pixel (field of view) measuring 200-300 mm square, but cannot discriminate between skeleton weed and other live plant material.
Survey of naturalized pampas grass (Cortadeeria selloana) in Western Austalia.
Perth, Albany, Waroona, Bunbury, Dardanup, Capel, Donnybrook/Balingup, Busselton, Augusta/Margaret River, Nannup, Bridgetown./Greenbushes and Manjimup.
The survey showed that infestations were found in the lower south-west, around Albany and in the Perth metropolitan area. In the lower south-west, it was recorded in the following shires: Waroona, Bunbury, Dardanup, Capel, Donnybrook/Balingup, Busselton, Augusta/Margaret River, Nannup, Bridgetown/Greenbushes and Manjimup.
Naturalized populations of pampas grass were found mostly in disturbed habitats in townsites and roadsides. There was little evidence that pampas grass was invading native vegetation.
Number of Pages
Dodd, J. (1990), Declared plants - biology, ecology and biocontrol.. Department of Agriculture and Food, Western Australia, Perth. Report.