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The dairy industry provides an important contribution to the Australian economy, but its productivity relies on grass pastures that suffer significant damage from invertebrate pests. Managing these pests remains a challenge as information on their abundance and impact is only available for a handful of taxa in a few Australian dairy regions. In this study, we undertook an extensive survey of above‐ and below‐ground pest communities across seven dairy regions in south‐eastern Australia by repeatedly sampling 57 paddocks in 2017 and 2018. We then applied energetic models to estimate the amount of metabolisable energy produced by pastures that are potentially consumed by pests. Our survey indicates that dairy farmers encounter a similar composition of above‐ground pests in most sampled regions, with a few pests, especially Sminthurus viridis (lucerne flea) and Rhopalosiphum padi (bird cherry‐oat aphid), dominating pest communities. Below‐ground pests were more variable between regions and are more likely to require region‐specific control strategies. Our energetic modelling suggests that pests consume a threefold greater percentage of metabolisable energy produced by pastures during autumn than spring. S. viridis and R. padi were among the most economically important pests across all regions and seasons, while other pests, including several species of scarabs and the small pointed snail, Prietocella barbara, were predicted to be particularly damaging in specific regions. Together, our field survey and energetic modelling provide baseline information to assist dairy farmers manage invertebrate pests and help guide future research in the Australian dairy industry. [ABSTRACT FROM AUTHOR]

The aphid Aploneura lentisci is widespread in Australia and New Zealand, living all year round on roots of its secondary grass hosts. The fungal endophyte (Epichloë festucae var. lolii), strain AR37 in Lolium perenne is known to greatly reduce populations and was a likely reason for the superior growth and persistence of this association previously observed in the field. Aphid populations were quantified in a field trial near Ballarat, comparing yields of perennial ryegrass infected with eight different endophyte strains and an endophyte-free (Nil) control in a common ryegrass background (Grasslands Samson (G. Samson)). AR37 and another endophyte strain, AR5, had significantly fewer aphids than all other endophytes. These differences were significantly related to yield increases taken before and after sampling that persisted until the end of the trial. In a pot trial comparing commercially available ryegrass-endophyte combinations with equivalent Nil controls, aphid numbers were lower on G. Samson AR37 and Banquet II with AR5 (Endo®5) than on all other cultivar-endophyte combinations. Compared with Nil controls, the common toxic strain in G. Samson, and two strains in Trojan also reduced aphid numbers. The AR5 endophyte produces the alkaloid ergovaline but high concentrations of this in roots of potted plants could not account for differences in root aphid numbers. Root concentrations of epoxyjanthitrems, the only known alkaloids produced by AR37, were low and unlikely to be the cause of resistance to A. lentisci. An aphid, Aploneura lentisci , that feeds on grass roots is widespread in pastures in New Zealand and Australia. This paper reports data confirming that perennial ryegrass infected with a strain of Epichloë fungal endophyte, AR37, is highly resistant to this aphid and shows that another endophyte strain, AR5, gives the same level of control. Suppression of high aphid populations by these endophytes in the field at Ballarat resulted in a 37% increase in pasture production over endophyte-free ryegrass over a 5-month period. [ABSTRACT FROM AUTHOR]

When interpreting statutes, courts presume that Parliament intended the statute to bear a meaning which is constitutionally valid. When this presumption is applied unyieldingly, it can result in statutes being ascribed meanings which are unnatural, vague and changeable. That can impair the rule of law values of predictability and continuity in the law. This article argues that rule of law values can play a role in the constructional process -- both in general and particularly in the context of reading statutes in conformity with the Constitution. The article explores this through an examination of two 2012 High Court decisions and proposes a set of interpretive maxims which courts could apply to temper unrestrained application of the presumption that statutes should be ascribed a meaning which is constitutionally valid. [ABSTRACT FROM AUTHOR]