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Four hundred and nineteen pasture soil samples yielded 132 M. anisopliae var. anisopliae isolates, which were classified into 14 strains. The distribution of the strains varied with soil-type and average annual rainfall. Soil pH, conductivity, temperature and altitude had minor or no effect on distribution. Canonical Variate Analysis as used to plot the relative positioning of strains in relation to the environmental variables. The densities of strains (c.f.u. g−1 soil) were not significantly different (P > 0·05). Modal density was 1 × 103 c.f.u. g−1 soil. The density was not correlated with any of the environmental variables examined.

Two hundred and four cultures of Metarhizium anisopliae var. anisopliae isolated from Tasmanian pasture soils were studied. Sixteen strains are distinguished by temperature requirements for germination and growth, conidial dimensions and sporulation colour. Hierarchical cluster analysis supports this classification. A key to the strains is provided. Pathogenicity testing of 184 of the cultures revealed that 50% (15/31) of isolates from one dendrogramic branch were pathogenic for L3 larvae of the scarab, Adoryphorus couloni. Only 4% (6/153) were found to be pathogenic amongst the other strains.

Soil water, runoff amount and quality, pasture production and environmental data were measured for a pastoral prime lamb enterprise in the Central Tablelands of New South Wales from 1998 to 2002. There were 4 pasture treatments: fertilised and sown chicory (CH), fertilised and sown introduced pastures (SP), fertilised naturalised pastures (FN) and unfertilised naturalised pastures (UN). Two grazing management regimes, tactically grazed (TG) and continuously grazed (CG) were imposed on the SP, FN and UN treatments. The CH treatment was rotationally grazed. To compare pasture and grazing system water use, maximum soil water deficit values (SWDMax) were calculated from neutron moisture meter data. SWDMax was influenced by both environmental and management factors. Management factors that influenced SWDMax were herbage mass of perennials, degree of perenniality, and the perennial species present. Environmental factors accounted for >50% of the variation in SWDMax. Inclusion of management factors (perennial herbage mass of C3 and C4 species and percentage perennial herbage mass), accounted for an additional 16% of variation. While the influence of pasture management appears to be relatively small, importantly, management is the only avenue available to land managers for influencing SWDMax. The UNTG and all sown treatments, with greater perennial herbage mass or greater C4 herbage mass consistently produced the highest SWDMax. Runoff amount and quality data are presented for ground cover percentages which generally exceeded 80% for the experimental period. Runoff as a proportion of rain received during the experiment was