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Background and Aims We evaluated three native plants to determine their capacity to provide insectary benefits to predatory arthropods in vineyards, and thereby to enhance biological control of insect pests. Native plants are preferred as supplementary flora, as they are naturally adapted to Australia's climatic conditions. Methods and Results Stands of mature Bursaria spinosa, Leptospermum continentale and Rytidosperma ssp. located adjacent to or in the mid‐rows of Adelaide Hills and Barossa Valley vineyards were sampled for arthropods in 2013/14. Vitis vinifera was also sampled. Twenty seven thousand and ninety‐one individual invertebrate specimens were collected, comprising 20 orders and 287 morphospecies. Nine thousand and thirty‐six predators, 6790 herbivores and 11 265 other specimens were collected. Predatory arthropods dominated the diversity of morphospecies present on each plant. Out of 100 predatory morphospecies, 69 were found on B. spinosa, 65 on L. continentale, 55 on V. vinifera and 37 in association with Rytidosperma ssp. The difference between predatory and herbivore morphospecies was highest on Rytidosperma ssp. (2.18:1 predators : herbivores), followed by L. continentale, V. vinifera and B. spinosa. Conclusions Bursaria spinosa and L. continentale have the potential to be used as insectary plants in association with Australian vineyards, as they support populations of predatory arthropods throughout the year. Rytidosperma ssp. could provide insectary benefits on sites where the black Portuguese millipede, Ommatoiulus moreleti, is not considered to be a problem. Significance of the Study This study confirms associations between predatory arthropods and three native plants. The opportunity to plant selected native insectary species could help winegrape growers save time and resources by producing fruit with lower pest incidence, while enhancing biodiversity of their vineyards.

Native grasslands, and the fauna that inhabit them, are globally some of the most threatened ecosystems and organisms. Knowledge of the relative importance of climate, landscape context and site-based resources for local insect populations is critical for the restoration and conservation of these communities. We investigated the site and landscape-scale best predictors of occurrence and abundance over three consecutive years of sampling, for the critically endangered golden sun moth Synemon plana in south-eastern Australia. We found eight vegetation factors to be significantly associated with golden sun moth occurrence using data from combined survey data and data for each year alone; we identified just three common factors from year to year. Modelling indicated that Austrostipa and Rytidosperma species richness was the most consistent parameter, but for each year alone, there was a combination of aspect, landscape position and Austrostipa and Rytidosperma species richness. Our study shows that environmental characteristics where golden sun moth occur are relatively predictable over multiple years. This information can be used to protect sites where monitoring of extant populations is yet to occur, predict the location of new populations in the region, and restore adjacent habitat that is suitable but degraded.

We provide a summary of two recent studies that investigated the role that three native insectary plants can play in promoting predatory arthropods, and thereby to enhance biological control of vineyard pests in Australia. Native plants are preferred as supplementary flora, as they are locally-adapted to Australia's climatic conditions. Stands of mature Bursaria spinosa, Leptospermum continentale and Rytidosperma ssp. located adjacent to, or in vineyards, in South Australia were sampled for arthropods in 2013/14. Grapevines were also sampled to explore relationships between each plant and associated arthropods using common diversity indices. Twenty seven thousand and ninety-one individual invertebrate specimens were collected, comprising 20 orders and 287 morphospecies. These were categorised into functional groups of predators, herbivores and other. Predatory arthropods dominated the diversity of morphospecies present on each plant. The richness of predator morphospecies across all plant types was nearly double the number found in association with grapevines. It may be possible to increase the functional diversity of predatory arthropods by more than 3x when either B. spinosa or L. continentale is present versus grapevines only, and increase the net number of predator morphospecies by around 27% when Rytidosperma ssp. are planted in combination with grapevines. The selected plants provide a suitable habitat to support diverse and functional populations of predatory arthropods. The opportunity to plant selected native insectary species could help wine grape growers save time and resources by producing fruit with lower pest incidence, while enhancing biodiversity associated with vineyards.

Background and aims The ability of plant lineages to reach all continents contributes substantially to their evolutionary success. This is exemplified by the Poaceae, one of the most successful angiosperm families, in which most higher taxa (tribes, subfamilies) have global distributions. Due to the old age of the ocean basins relative to the major angiosperm radiations, this is only possible by means of long-distance dispersal (LDD), yet the attributes of lineages with successful LDD remain obscure. Polyploid species are over-represented in invasive floras and in the previously glaciated Arctic regions, and often have wider ecological tolerances than diploids; thus polyploidy is a candidate attribute of successful LDD. Methods The link between polyploidy and LDD was explored in the globally distributed grass subfamily Danthonioideae. An almost completely sampled and well-resolved species-level phylogeny of the danthonioids was used, and the available cytological information was assembled. The cytological evolution in the clade was inferred using maximum likelihood (ML) as implemented in ChromEvol. The biogeographical evolution in the clade was reconstructed using ML and Bayesian approaches. Key results Numerous increases in ploidy level are demonstrated. A Late Miocene-Pliocene cycle of polyploidy is associated with LDD, and in two cases (the Australian Rytidosperma and the American Danthonia) led to secondary polyploidy. While it is demonstrated that successful LDD is more likely in polyploid than in diploid lineages, a link between polyploidization events and LDD is not demonstrated. Conclusions The results suggest that polyploids are more successful at LDD than diploids, and that the frequent polyploidy in the grasses might have facilitated the extensive dispersal among continents in the family, thus contributing to their evolutionary success.

Fifteen species of indigenous grasses are considered to be at some conservation risk. One species of Poa is dioecious; all other taxa bear perfect flowers. Self-compatibility is common and expressed as cleistogamy in Bromus arenarius. Rytidosperma tenue appears to be sterile; no other species is at particular risk because of its breeding system.

SUMMARY (1) In a perennial grassland undergoing succession after the removal of domestic grazers, three natural processes could disrupt the canopy, and thus affect colonization. These are: canopy gap formation due to the death of individual bunchgrasses; soil disturbance by gophers; and grazing by native animals. (2) Species' abilities to colonize canopy gaps and gopher mounds were assessed in the field, with seed introduction experiments, for the five most cover-dominant grass species: Anthoxanthum odoratum, Holcus lanatus, Deschampsia holciformis, Rytidosperma pilosum (all perennial bunchgrasses) and Vulpia bromoides (an annual grass). (3) The effects of native grazers on colonization by the most abundant species, Anthoxanthum, were assessed, using grazer exclosures and seed introductions in annualdominated vegetation, where grazing activity was highest. (4) Colonization success was quantified as total leaf area, number of survivors and seed production, in sites where seeds of the colonist either fell naturally, or were introduced at natural densities. (5) The formation of canopy gaps by the death of individual bunchgrasses and soil disturbances by gophers strongly affected colonization success. The best colonizers were Anthoxanthum and Holcus, whose colonization success was increased 6-2500-fold by canopy gap formation, and 10-200-fold by the formation of gopher mounds. Few, small seedlings of Deschampsia and Rytidosperma survived in canopy gaps or on gopher mounds. Unlike Anthoxanthum and Holcus, Deschampsia and Rytidosperma did not reproduce in gaps or on mounds over a two-year period. (6) Vulpia colonists had higher seed production on mounds than the four perennials. Vulpia also colonized canopy gaps, but was excluded by perennial vegetation in the second year of growth in the gaps. (7) In annual-dominated vegetation, neither aboveground biomass nor colonization by Anthoxanthum was affected by excluding grazers. However, exclusion of grazers led to an increase in the cover of forbs after two years. Clipping aboveground vegetation allowed Rytidosperma to achieve dominance in sites where, under undisturbed conditions, it existed only as a suppressed understorey. All other perennials were negatively affected by clipping. (8) The species with the highest natural densities of seed rain also had the greatest perseed colonization success, even though negative density-dependent effects must have been