SUSTAINABILITY & RESOURCES PROJECT NUMBER: PN07.4027 MAY 2008 Review of Alternative Pine Species for Low-Rainfall Zones of Australia This report can also be viewed on the FWPA website www.fwpa.com.au FWPA Level 4, 10-16 Queen Street, Melbourne VIC 3000, Australia T +61 (0)3 9614 7544 F +61 (0)3 9614 6822 E [email protected] W www.fwpa.com.au Review of Alternative Pine Species for Low-Rainfall Zones of Australia Prepared for Forest & Wood Products Australia by M. J. Dieters Publication: Review of Alternative Pine Species for Low- Rainfall Zones of Australia Project No: PN07.4027 © 2008 Forest & Wood Products Australia Limited. All rights reserved. Forest & Wood Products Australia Limited (FWPA) makes no warranties or assurances with respect to this publication including merchantability, fitness for purpose or otherwise. FWPA and all persons associated with it exclude all liability (including liability for negligence) in relation to any opinion, advice or information contained in this publication or for any consequences arising from the use of such opinion, advice or information. This work is copyright and protected under the Copyright Act 1968 (Cth). All material except the FWPA logo may be reproduced in whole or in part, provided that it is not sold or used for commercial benefit and its source (Forest & Wood Products Australia Limited) is acknowledged. Reproduction or copying for other purposes, which is strictly reserved only for the owner or licensee of copyright under the Copyright Act, is prohibited without the prior written consent of Forest & Wood Products Australia Limited. ISBN: 978-1-920883-51-5 Researcher: M. J. Dieters The University of Queensland School of Land, Crop and Food Sciences Brisbane, Qld. 4072 Australia Final report received by FWPA in February, 2009 Forest & Wood Products Australia Limited Level 4, 10-16 Queen St, Melbourne, Victoria, 3000 T +61 3 9614 7544 F +61 3 9614 6822 E [email protected] W www.fwpa.com.au Summary A review was conducted of pine species with potential for application in plantation forestry on ‘low-rainfall’ sites in New South Wales, Queensland, South Australia and Western Australia, under this FWPA-funded project. Here ‘low-rainfall’ sites are defined as sites that experience rainfall lower than the traditional sites for growing commercial pine plantations with Pinus radiata in southern and western Australia, and P. caribaea and P. elliottii hybrids in Queensland. It is now very difficult to import either seed or vegetative material of any Pinus species into Australia due to the risk of pine pitch canker. Therefore, pine germplasm existing within Australia will need to provide the genetic diversity to support the long-term viability of the softwood plantation industry. Similarly, expansion of pine plantations into marginal, low-rainfall environments will need to utilise genetic diversity (both within and between species) extant within Australia. In addition to P. brutia, P. halepensis and P. pinaster, the review of pine species planted in trials, arboreta and other tests identified a number of species of potential interest for deployment either as pure species or hybrids on marginal sites throughout Australia, including: P. ayachuite, P. canariensis, P. eldarica, P. greggii, P. leiophylla, P. maximinoi, P. pinea and P. taeda. Currently, these species are regarded as only of peripheral interest for plantation forestry, which currently is primarily restricted to traditional, higher-rainfall sites (see above). As a result, there is a risk that genetic material of these and other pine species currently in Australia will be lost or eroded in the short to medium term. A gene conservation strategy is recommended. This strategy would involve, for each of the key species identified: review of all known plantings of these species throughout Australia; selection of approximately 200 phenotypically superior trees (selected primarily on stem and crown form); and, grafting of the selected trees into clonal archives on at least two sites. This strategy is similar to that which has already been applied in P. brutia under the ALRTIG program. Compared to gene conservation based on seedlings, under the recommended strategy a relatively small number of trees per species are maintained in archives. Although establishment costs may be relatively high (perhaps $10-15 per grafted tree) the amount of land involved is relatively small, and selected genotypes are preserved. These grafted trees can be used for a number of other purposes in the future, including: production of seed, parents in crossing and hybridisation programs, and association genetics studies. This approach could also be applied the major Australian pine species (e.g. P. radiata and P. caribaea), as well as to other pine species of potential interest (e.g. P. oocarpa and P. tecunumanii which are known to have high levels of resistance to pine pitch canker in some populations). P. oocarpa and P. tecunumanii are currently only of marginal interest for plantation forestry in Queensland, but superior individuals that have been selected and tested should be preserved in the national interest. Should pine pitch canker enter Australia, species such as this may provide the only significant source of resistance to this disease. 2 Introduction Significant expansion in the Australian softwood plantation estate is required to meet the projected future requirements for timber and paper products in Australia, and to allow enhanced efficiency/scale of processing industries based on this resource. However, both the cost and availability of land limits the expansion of plantations within the environments which have traditionally been regarded as suitable for commercial plantations of Monterey pine (Pinus radiata) in southern/western Australia (mean annual rainfall typically greater than 800 mm) and slash (P. elliottii) and/or Caribbean (P. caribaea var. hondurensis) pines in Queensland (mean annual rainfall typically greater than 1200 mm). For example, it is has been projected that between 20,000 and 90,000 ha of new pine plantation in southern NSW in areas west of the Hume Highway will be required to supplement the Tumut plantation resource. Also, representatives of the processing industry in Queensland have called for an expansion of the pine plantation resource, suggesting at least 20,000 hectares be established in areas such as lower-rainfall and colder areas north-west of Maryborough and in the Brisbane Valley around Kingaroy. Similar trends are likely in Western Australia to satisfy increasing demands from growing urban populations, and to permit greater regional development in areas such as Esperance. Ideally, expansion of the existing softwood plantation resources should aim to supply wood with timber of similar quality and processing requirements to that produced from the much larger areas of pine plantations on conventional sites. Trials of some alternative species have been conducted in the past on marginal sites, in or near these regions of interest. Hybridization of slash/Caribbean, Monterey and maritime (P. pinaster) pines with more drought- and/or cold-tolerant species may provide a solution to the dual problems of increasing tolerance to abiotic stresses, while maintaining consistency of timber quality. Nevertheless, it is expected that there will be considerable genetic variation within Monterey and Caribbean pines that can be exploited in marginal environments, and at the extreme rainfall limits for commercially viable pine plantations species such as P. brutia, P. eldarica, and P. halepensis or hybrids with these species may be required in southern and western Australia, and of some Mexican-Central American pines in south-east Queensland. The principal objectives of this study were to: i) collate information on the performance of alternative pine species and hybrid combinations in the lower-rainfall zone; ii) produce web-accessible data on the availability and nature of germplasm from alternative pine species in Australia; and, iii) summarize all available information on species and hybrid combinations with the highest potential in these lower-rainfall environments of Australia. Approach Used This study was led by the University of Queensland (UQ), but represents the outcome of collaboration between UQ and the New South Wales, Queensland, South 3 Australian and Western Australian agencies responsible for forest plantation establishment and/or research: that is, Forests NSW (FNSW), Forestry Plantations Queensland (FPQ) and Horticulture and Forestry Science (H&FS) in Queensland, Primary Industries and Resources South Australia (PIRSA) and ForestrySA in South Australia, and Forest Products Corporation (FPC) in Western Australia. Each organisation contributed information on the pine species that had been grown and/or evaluated in each State, and that were potentially adapted to growing on lower-rainfall sites of Australia. Data (either raw data or summary data) were also contributed on trials from sites regarded as being marginal for commercial pine plantations in each of these regions. Germplasm – Species of Potential Interest The first objective of this project was to review the range of pine species (and hybrids) that had been evaluated by the partner agencies, and which had some potential for use in the lower-rainfall zones of Australia. Species would need to have some level of known or inferred tolerance of drought and/or cold. A full-list of Pinus species of potential interest for the lower-rainfall zones of Australia, and which have been grown in Australia, is reproduced in Appendix 1. The major Pinus species used in commercial plantations in Australia is P. radiata, and is highly susceptible to pine pitch canker (Hodge and Dvorak, 2000). Pitch canker is endemic to the south-eastern USA, and was first detected in California in 1986 (Gordon, 2006) where it has caused significant mortality to native stands of P. radiata. P. elliottii and P. caribaea are also susceptible to pitch canker; however, the level of mortality is not as severe and low-elevation sources of P. oocarpa and P. tecunumanii show nearly complete resistance as seedlings (Hodge and Dvorak, 2000).