Get reliable rangeland science

Drylands worldwide face severe degradation, requiring restoration efforts that often rely on native plant species. However, the small seed size of some species poses challenges for conventional seeding machinery. In Western Australia, the "Comm Veg" seeder is commonly used, creating furrows to improve seedling establishment. To address limitations in seed distribution and sowing speed, seed pelleting technology was explored to increase seed size, enabling the use of a crop seeder (A itchison). A field experiment in Eganu, WA (July 2024), compared seedling emergence and survival of four native species (Eucalyptus oldfieldii, Melaleuca cordata, Eremaea pauciflora, and Acacia pulchella) sown as bare seeds using the Comm Veg and as pelleted seeds using the crop seeder. Seedling emergence was measured in early (September) and mid-spring (November). A glasshouse experiment assessed germination rates of bare versus pelleted seeds. Glasshouse results showed similar germination rates for bare and pelleted seeds across species. In the field, seedling emergence was higher with the Comm Veg seeder, likely due to greater soil moisture storage in the deep soil layer (7 –15 cm) in furrowed areas. Alive Acacia seedlings exhibited significantly longer roots than dying seedlings, indicating deeper moisture access. However, seedling mortality was high for all species by mid-spring (<2% survival), likely due to late sowing and frequent droughts. Although crop seeder showed lower effectiveness in conserving soil moisture and supporting seedling survival, integrating agricultural machinery with seed pelleting technology remains promising for cost-effective, large-scale restoration. Refining sowing techniques and pelleting methods is essential to improve restoration success in degraded drylands.