High standards in managing the seed-supply chain, emphasizing sourcing and seed storage, are crucial to maintaining seed viability and ultimately to meeting restoration goals. The germination of 40 plant species was investigated in response to difficulties experienced by restoration practitioners in propagating them from seed in nurseries and in direct seeding. The species were from a biodiversity hotspot in inland eastern Australia and spanned a range of life-forms. The initial constraint identified was poor seed viability, which varied widely within and between species but was < 50% in at least one seedlot of 36 species. Low seed viability was indicated by poor seed storage and processing practices, manifest in excessive storage time, herbivory, fungal infection, and inadequate seed collection and processing (e.g. collection of immature seed and overcleaning). The main reason for low germination of viable species was seed dormancy. Dormancy was identified in 16 species: pre-sowing treatments in these species were effective in relieving dormancy or increasing germination percentage by two to three-fold. The most frequent pre-sowing treatment required was scarification. Stratification, de-husking and leaching also increased germination in some species. Temperature conditions for high germination were also investigated. Seasonal temperature treatments affected germination in 22 species. The results emphasize the necessity for (1) testing seed before use; (2) identifying temperature ranges to achieve maximum germination; (3) identifying species with germination constraints, and (4) using suitable pre-sowing treatments for plant propagation in nurseries and potentially in the field.

Cloud forests and savannas differ in several environmental aspects, particularly in light irradiance and water availability. Such differences can be selective for specific sets of leaves and architectural strategies to capture light and use water. In the present study we evaluated functional traits variation in a generalist species in two adjacent habitats experiencing an abrupt change in resource availability (light and water availability). We collected several leaf, stem and architectural traits of the tree species Eremanthus erythropappus (DC.) MacLeish in shrubland savanna (habitat facing higher drought stress and wind exposure) and cloud forest (shaded environment). Trees in the shrubland savanna exhibited functional trait values that enhance drought tolerance (i.e. higher wood density and leaf thickness) whereas trees in the cloud forest exhibited functional trait values that enhance light capture (i.e. taller individuals with higher leaf area and specific leaf area). Additionally, the individuals in the shrubland savanna had wider and deeper crowns, pointing that the benefits of a larger canopy area to capture light during the day and humidity from condensation at night exceed the higher risk of mechanical damage by falling debris due to high wind exposure. For all traits, variation among the individuals was lower than variation among habitats. Our results indicate the strong role of the environment as a driver of intraspecific variation and that architectural traits (usually poorly studied compared with other traits) should be included as an important parameter of variation in functional analyses when evaluating the effect of environmental conditions on tree performance.

Restoring the grassy understorey to temperate woodlands in south-eastern Australia is often disregarded due to a poor understanding of the techniques involved. The natural recruitment of native grasses is uncommon in the remnants of some of these woodlands, so the restoration of the grass layer is often dependent on interventions to overcome restoration barriers. Soil enrichment from agricultural fertilisers favours the invasion of exotic broadleaf weeds and grasses, and is one of the primary barriers to the successful recruitment and establishment of native grasses, which dominated before agricultural development. This study on the Northern Tablelands of New South Wales investigated the effects of different weed control treatments – scalping, glyphosate (Roundup®) herbicide, and combinations of glyphosate with carbon (sugar and sawdust) addition and a control (nil treatment) recruitment of native grasses and weed emergence after broadcast seeding. The experimental site was a mown grass lawn consisting of fescue (Festuca arundinacea Shreb.), cocksfoot (Dactylis glomerata L.) and paspalum (Paspalum dilatatum Poir). Native grass recruitment varied significantly between treatments. The maximum number of recruits in scalped plots was 29 recruits m–2 compared with an average of <2 recruits m–2 for the glyphosate and glyphosate carbon combinations. Scalping reduced soil nitrogen from 0.6% in non-scalped plots to 0.1% and phosphorus from 191.6 ppm to 40.3 ppm. Maximum weed cover occurred in the glyphosate herbicide treatment (45%), whereas combinations of glyphosate plus either sugar or sawdust maintained weed cover at 13%. The present study suggests that scalping may be a successful intervention strategy because it has the potential to significantly improve native grass recruitment compared with other restoration methods used in this study. Scalping allows more time for native grasses to germinate and establish in the absence of competitive fast-growing exotic weeds.