REVEGETATION PLAN WILLIAMS LOCATIONS 7345 AND 8651 (“CHADWICK’S”) PREPARED FOR THE DEPARTMENT OF CONSERVATION AND LAND MANAGEMENT PREPARED BY ARBORESSENCE CONSULTANCY APRIL 2001 Revegetation Planning- “Chadwick’s” Toolibin Index Introduction 3 Specific recommendations 4 Revegetation plan 5 Introduction 5 Plantings 6 Seed production areas 6 Melaleuca plantings 6 Buffer plantings 6 Symbiotic fungi 6 Native grasses plots 6 Seed production areas 7 Introduction 7 Species list 8 Seed availability 9 Matching species to site 10 Plantings patterns for individual plots 12 Melaleuca plantings 22 Buffer plantings 24 Species lists 25 Symbiotic fungi 28 Native grasses plots 29 Plot layout 30 Non-endemic vegetation 36 Site preparation recommendations 38 Ripping 38 Mounding 39 Weed control 49 Control of vermin and grazing animals 40 Planting 40 Monitoring 42 Roading and fencing 44 References 45 Appendix A Inez Tommerup and Neale Bougher (2001). Draft proposal to include fungi to improve biodiversity qualities and soil process functions in rehabilitation model for Lake Toolibin 2 Revegetation Planning- “Chadwick’s” Toolibin Lake Toolibin Project-Chadwick’s revegetation Introduction The Department of Conservation and Land Management has acquired a 135 ha section of farmland in the Lake Toolibin catchment, to the north of and adjoining a system of nature reserves. It is proposed to revegetate this farmland. Aims The principal aim of this revegetation is to: Contribute to the hydrological stability of the Toolibin catchment for protection of the nature conservation values of the nearby nature reserve system, in particular Lake Toolibin. Revegetation can further this aim through reducing the impact of rising water tables (Bartle et al. 1996) and reducing the salinity of surface water flows. Specifically, it is proposed that this be achieved through the establishment of high water use perennial plants capable of using water beyond annual rainfall, where ground water salinities permit. Secondary aims of the revegetation work include: • expanding and buffering the reserve system, and developing the connectivity of the existing reserves. • demonstrating an alternative commercial land use based on endemic perennial species. • maximising biodiversity values of revegetation, within the above constraint. • minimising the undesirable outcomes of revegetation, such as proliferation of weed species and increased fire risk. • demonstrating planning, establishment and management techniques that are transferable to farmland revegetation in the surrounding catchment and other parts of the Wheatbelt. • providing significant amounts of quality seed of local species for further revegetation work within the adjoining CALM estate and farmland within the catchment. These actions are supportive of the five principal goals of the Toolibin Lake Recovery Plan (Toolibin Lake Recovery Team and Toolibin Lake Technical Advisory Group, 1994). 3 Revegetation Planning- “Chadwick’s” Toolibin Specific recommendations To achieve the above aims it is recommended that: • The entire area be planted over a period of five years, subject to budget and staffing constraints. This would include one year of site assessment and planning (2001), three years of major planting programs, and a year of infill and maintenance following final major planting (2005). • That the majority of the land be dedicated to seed production areas to increase the availability of quality, local provenance seed for ongoing revegetation in the region. • That plantings consist of combinations of species commonly occurring together in the surrounding areas, matched, as near as is practical in an operational sense, to the landforms and soil types of the project area. • That the dimensions of the mature plant guide the planting density of any given species. For example, in a seed production plot, large trees will be planted at a low density of trees per hectare, with an understory of smaller plants at higher density. This is not currently common practice in revegetation. • That the revegetation initially includes a high percentage of high litter producing and nitrogen fixing species. This will increase soil carbon, reduce surface temperature variation, reduce erosion and create surface conditions conducive to a more complex environment, fostering, for example, fungi and invertebrate populations. • That plantings be relatively dense, (average density of 1000 stems per hectare), and include a high percentage of shrubs to give fast shade and shelter. This will create significant microclimate change on a site that is currently very exposed. • That significant plantings of melaleucas for the production of essential oil (and other products as appropriate) be established. • That significant plantings of hard seeded plants such as Acacias be included throughout the plantings as a buffer against catastrophic fire. These plants, the “pioneer” species, grow quickly and afford shelter to minimise erosion on the site and create conditions more conducive to healthy populations of invertebrates, fungi, etc. • That a safety margin be included in determining salt tolerance of any planting, as a buffer against increasing salinity. • That agroforestry layouts not be a principal aim of the plantings. The wider dispersal of agroforestry plantings, and issues of stock management are considered to compromise the hydrological and nature conservation imperatives listed above. Significant potential exists for agroforestry demonstration and trial on farmland outside the reserve system, where there is abundant cleared farmland, and realistic everyday stock management can be applied. If farmers in this region are not currently taking up revegetation opportunities, the issue of adoption of agroforestry practice must be dealt with separately. This is outside the scope of the recommendations in this report. • That non-endemic species (all planted prior to the property being purchased by CALM) with potential to become weeds within the reserve system be removed and replaced with more appropriate vegetation in the third year of planting. 4 Revegetation Planning- “Chadwick’s” Toolibin The revegetation plan Note: This report accompanies, and should be read in conjunction with, a series of overlays showing location of revegetation and other site works. Introduction Throughout this report the name “Chadwick’s” is used to refer to Williams Locations 7345 and 8651, purchased by the Department of Conservation and Land Management from the Chadwick family. Better connectivity between reserves adjoining different parts of Chadwick’s block will be developed by the revegetation plantings. The most important corridor is to the west, from Dingerlin Nature Reserve across to Dulbinning Nature Reserve. The existing direct seeding area forms the first part of this connection. Canal road forms a permanent barrier to this corridor, however it is narrow with reasonable road verge vegetation and little traffic. Surveying the remnant vegetation suggests Canal road was probably also a boundary between vegetation types, separating scrubland and heath vegetation from more woodland species. The eastern side of the property is less critical because there are already good connections through the reserve system to the south of Chadwick’s. Additionally, this side has the barriers of Oval road and of a major drain, which will need to be kept relatively clear for maintenance. Consideration could be given to reducing the height of the drain’s spoil bank (spreading) to facilitate the movement of animals. The long-term aim in these corridor areas is to build up a complex vegetation structure and a rich biotic layer on the ground. These sites may be added to in the future, but should receive minimal disturbance, to enhance their nature conservation value. Other areas will be dedicated to trial plantings, seed production areas and other “utility” plantings. In contrast to the corridor plantings mentioned above, some of the may be seen as having a limited life. For example, an oil melaleuca seed production area might become obsolete for this purpose as successive generations of improved seed production and seed orchard areas are established. Its role can be revised in future, for example to general revegetation seed supply, a nature conservation planting, or the land use changed. The proposed plantings are grouped into those tolerant of saline conditions, and those that require fresh ground. The eastern side of the block is variable in salinity but relatively flat, making even those areas currently fresh vulnerable to influences from the surrounding catchment. The western side is more complex, running from hyper-saline low lying flats up to fresh, deep soil profiles. In year four of the revegetation plan (year three of planting) some of the non-endemic plantings can be removed and replaced. These plantings pre-date the purchase of the property by CALM, and are discussed later in the document. 5 Revegetation Planning- “Chadwick’s” Toolibin Plantings Species and layouts for proposed plantings are detailed below. The recommendations are in four major areas: 1. Seed production areas 2. Melaleuca plantings 3. Buffer plantings 4. Symbiotic fungi There are additional separate references to the revegetation of an isolated triangle of land in the SE corner of the area, and to a research plot for native grasses. Seed production areas It is recommended that the plants listed below in this section be grouped into compatible combinations, including nitrogen fixing species, allowing co-occurrence