Schefflera digitata

Abstract: Climate change may facilitate alien species invasion into new areas, particularly for species from warm native ranges introduced into areas currently marginal for temperature. Although conclusions from modelling approaches and experimental studies are generally similar, combining the two approaches has rarely occurred. The aim of this study was to validate species distribution models by conducting field trials in sites of differing suitability as predicted by the models, thus increasing confidence in their ability to assess invasion risk. Three recently naturalized alien plants in New Zealand were used as study species (Archontophoenix cunninghamiana, Psidium guajava and Schefflera actinophylla): they originate from warm native ranges, are woody bird-dispersed species and of concern as potential weeds. Seedlings were grown in six sites across the country, differing both in climate and suitability (as predicted by the species distribution models). Seedling growth and survival were recorded over two summers and one or two winter seasons, and temperature and precipitation were monitored hourly at each site. Additionally, alien seedling performances were compared to those of closely related native species (Rhopalostylis sapida, Lophomyrtus bullata and Schefflera digitata). Furthermore, half of the seedlings were sprayed with pesticide, to investigate whether enemy release may influence performance. The results showed large differences in growth and survival of the alien species among the six sites. In the more suitable sites, performance was frequently higher compared to the native species. Leaf damage from invertebrate herbivory was low for both alien and native seedlings, with little evidence that the alien species should have an advantage over the native species because of enemy release. Correlations between performance in the field and predicted suitability of species distribution models were generally high. The projected increase in minimum temperature and reduced frosts with climate change may provide more suitable habitats and enable the spread of these species.

Abstract: Falcarindiol [(9Z)-heptadeca-1,9-diene-4,6-diyn-3,8-diol] has been isolated in high yield from leaves of the N. Z. plant SCHEFFLERA DIGITATA but was not detected in other, closely-related, species of Araliaceae. Low concentrations of falcarindiol were found to inhibit the germination of spores of most common dermatophyte fungi.

Abstract: Seeds from freshly collected fruit from two provenances each of Aristotelia serrata, Coprosma robusta, and Schefflera digitata and one each of Cordyline australis and Myrtus obcordata were tested in an unheated, partially shaded glasshouse in Christchurch, to discover germination rates, percentage germination success, and phenomena related to germination delay. The treatments were designed to simulate conditions that the seeds might experience after dispersal (normally after being consumed by birds). In the standard treatment (cleaned, moist, well-lit), from collections made in summer (Aristotelia) and autumn (the other four species), most of the seeds of each species germinated in late summer, or autumn — mid winter. A small proportion of Aristotelia and Cordyline seeds overwintered and germinated in the following spring. Overall success was high for all species (90–100%). Seeds of each species placed in the dark, or on soil, germinated at similar rates and with similar success but only for Cord...

Abstract: The diet of the feral goat (Capra hircus) in rimu-rata-kamahi forest on Mt Taranaki was examined over 1 year from monthly rumen samples. Seasonal changes in diet, relative plant preference ratings, and differential fragmentation and digestion rates of plant species, were measured. Individual rumens contained 19 plant species on average and sometimes more than 30. Two species, (Asplenium bulbiferum and Ripogonum scandens), made up 44.8% of the total volume eaten over the year. Foods which were eaten in significantly different proportions by season included Coprosma grandifolia, Coprosma tenuifolia, Griselinia littoralis, Melicytus ramiflorus, Ripogonum scandens (fruit and vine), Weinmannia racemosa, and Dicksonia squarrosa. Goats selected or rejected different plant species largely independently of plant availability. Schefflera digitata was relatively scarce in the habitat, but was possibly the most preferred food. In contrast, the very abundant Microlaena avenacea, Uncinia spp., moss, Alsophila ...