Chapter 9

1 1 Chapter 9 Native VegetationEstablishment and ManagementTechniquesMartin DriverGreening Australia - Riverina The need for more vegetationAcross most of south eastern Australia,past clearing or land-use intensification,predominantly for agriculture, hasdramatically altered the native vegetationcover over the landscape. The Riverina has large areas with verylow existing tree cover, a virtually extinctshrub layer and a ground layer often (atleast seasonally) dominated by exoticannual pasture weed species.

2 Thissituation was not always the case. Inmuch of the landscape this decline ordegradation needs to be reversed in orderto address a range of issues andobjectives that affect the sustainability ofour rural industries and our your objectiveMost objectives for revegetating an areaor for retaining or enhancing existingremnant vegetation are included in thefollowing broad categories (that can oftenoverlap).Function Ecological functioning/ biodiversityprotection (provision of habitat/niche/ genetic diversity). Hydrological functioning (moderationof recharge/ discharge and soil waterflows) and salinity control.

3 Provision of landscape stability,perenniality, soil health andprotection (and stable production).Finance - Grazing potential and management. Wind/ weather protection. Timber, firewood, wildflowers, seed,oil, biofuels, by-product production. Tourism/ amenity and ecotourismvalues. Real estate and aesthetic - Local and regional landscape/ aesthetic values and distinctiveness. Lifestyle and amenity values(recreation). Spiritual/ land ethic values andresponsibilities (re-creation).Making the most of what youalready have making a planBefore any vegetation establishment ormanagement is undertaken it is importantto take stock of what is present and tohave a clear idea of which of the aboveobjectives you are trying to achieve for aparticular site (refer to Chapter 3).

4 Principles and priorities to getit first principle of vegetationmanagement and establishment is to2work with existing remnant vegetationon a site as a base for any in vegetation management andrevegetation at any scale should be to (indecreasing order) -1. Retain2. Regenerate3. Reseed4. Replace5. Replant The second principle of vegetationestablishment or management is to uselocally native species from localprovenance seed or genetic material asa priority in any revegetation works. Putting the principles andpriorities into action 1. Retain The identification and planned retentionof any existing remnant vegetation(woodland, shrubland, grassland orwetland) is the most important first stepin any vegetation plan.

5 The retention and management ofremnant vegetation provides thebackbone for ensuring that local geneticmaterials are retained and provides thebasic matrix for achieving a diverse andhealthy vegetation structure and habitatfor native (usually through fencing) andmanagement (of weeds and grazing) ofthese areas provides: a ready source of fresh seed or theopportunity for future seedproduction and natural regeneration; soil seed stores that are able tosuccessfully regenerate whenconditions are suitable; the opportunity of inducing regrowthand root suckering from those speciesthat respond to root disturbance (seeTable 1); and reference areas for core andsecondary species lists forrevegetation in the native vegetation has beenretained, it must be actively managed toensure that its condition does notdeteriorate and that it regenerates overtime.

6 Without regeneration (and gradualreplacement) all existing remnantvegetation is only temporary and will belost. Managing these areas forregeneration is critical to maintaining anyeffective vegetation grazing (domestic, feral andnative) and weed suppression are keymanagement actions when trying toregenerate native vegetation. Theseactions should aim to optimise the naturalregeneration potential of existing Regeneration SeedProducing SpeciesNot all species will regenerate under thesame conditions, nor will therenecessarily be regeneration every key principles in managing fornatural regeneration from seed andoptimising any opportunity for seasonalregeneration events are to: ensure that the existing trees andshrubs are healthy, flowering, andcapable of producing and settingviable seed (refer to Chapter 10).

7 Remove or manage grazing to favourregeneration opportunities,particularly in seasons and years ofabove average rainfall (refer toChapter 7). Areas of high diversity ingood condition or in recovery andparticularly palatable species ( seedlings) may be best3managed by removing grazing andhaving very long periods of rest; carefully monitor the site for earlysigns of a regeneration event. Goodplaces to look are around seedproducing trees, under regularly usedperch sites and ant nests; avoid disturbing natural, undisturbedareas with intact groundlayers; manage weeds the management (bystrategic grazing) or patch removal(by chemical, scalping, burning) ofexotic annual grass and broad-leavedweeds can significantly increase thechances of native seedlinggermination and survival.

8 And maintain and manage suitablepositions that provide microclimatedifferences for germination andpersistence, such as fallen logs, litter,shrubs, depressions, drainage linesand edge 1: Regeneration resulting fromcontrolled grazing and Regeneration RootSuckering Species There may be species on site that do notregenerate readily from seed or regularlyproduce seed. Some of these species canbe stimulated to regenerate by rootsuckering or vegetative regrowth (Table1).Table 1: Species that respond to rootdisturbance by root suckering (indescending order of response andreliability, based on personal observationand trialing).

9 Common NameBotanical NameRosewoodAlectryon oleifoliusEmubushEremophila longifoliaSandalwoodSantalum lanceolatumCooba/Native WillowAcacia salicinaHooked NeedlewoodHakea tephrospermaButterbushPittosporum phylliraeoidesNative JasmineJasminum lineareBoreeAcacia pendulaRiver CoobaAcacia stenophyllaYarranAcacia homalophyllaBulloakAllocasuarina luehmanniiSugarwoodMyoporum platycarpumRoot suckering can be stimulated byusing a tractor mounted single tyne ripperto break or damage surface roots (10-30cm deep) in a single pass some distanceout from the dripline but within thevisible root zone of the tree. Care must betaken not to break tree roots on all sidesof a single tree in the one year as this maymake it more susceptible to winddamage.

10 Best results occur after rippingin Reseed Where native vegetation has beenretained and managed some elements ofits natural complexity may still bemissing that are essential for ecosystemfunction. The missing floristic andstructural components of the originalvegetation need to be broad scale reintroduction of pre-treated shrub seed by direct seeding maybe the most significant and cost-effectivemanagement action. Appropriate grazing management toallow regeneration is essential. 4 There are several different direct seedingmethods and a range of different toolsand machines that may be appropriate fordifferent sites.