Identifying agricultural practices to sustain bamboo production in Queensland, Australia

Bamboo, as a relatively new plantation crop in Australia, requires an integrated agricultural strategy as a benchmark against which improvements to optimise productivity and maximise growers’ gross margin can be assessed. An important aspect of bamboo production is how to balance the productivity and returns from edible shoots and/or culms for timber. A 6-year trial was set up on an existing clumping bamboo (Bambusa oldhamii) grove at Eumundi, Queensland, Australia, from 2001 to 2006. Using conventional best management as a control (T1—fertilised, irrigated, early-season selection of shoots for timber culms, and designed wide clump space), five other treatment variations (T2—no irrigation during dry season, T3—late-season selection, T4—narrow spacing, T5—late-season selection, and harvesting excess shoots only as early thinning, and T6—non-irrigation, non-fertilisation, early-season selection) were imposed. Shoots and culms in each treatment were seasonally harvested during 2003–05, and the total production, i.e. fresh weight (FW) for shoots and dry weight (DW) and volume for culms, were summed for each treatment. Water-use efficiency for dry culms at c. 1.0 g/kg (total applied water plus precipitation) was not dissimilar to other species. There was a trade-off between shoot and culm production when the harvest of shoots as a vegetable was excessive. To compare bamboo productivity between treatments, a productivity index (PI) was calculated to convert the value of culm DW to relative market value of edible shoot FW using a range of ratios from 0.0–1.0 such that the value of 1 kg of culm was adjusted as a ratio of the value of 1 kg of edible shoot. We concluded that T3 was the best strategy for producing shoots only, T5 was the best for culms only, and T2 was the best for dual production of shoots and culms because it increased average relative water-use efficiency by 28%. However, the case study indicated that T3 was a financially sustainable management for growers in Australia regardless of the fluctuation in shoot and culm market prices. Additionally, a leaf chlorophyll meter proved to be reliable in estimating bamboo leaf nitrogen concentration as a guide to nitrogen fertiliser decisions.