Growing Broombush: for Fencing Products on Cleared Farmland



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Growing Broombush:

for Fencing Products on Cleared Farmland  

in Southern WA

By Chris Robinson and Tim Emmott

Greening Australia (WA)


INTRODUCTION

A number of 

Melaleuca species can be used in the con-

struction of brushwood fencing in Australia. These species

are often collectively referred to as "broombush". The most

common across southern Australia is 

Melaleuca uncinata,

originally collected by Robert Brown at Port Lincoln in South

Australia in 1802. It is a hardy, bushy shrub that grows to

4m tall, with little or no main trunk. It has many long, thin,

vertically orientated branches which are strong and hard,

topped with a canopy of long thin hook-tipped leaves. It is

widespread in the drier woodlands, mallee and heath, where

it is generally slow growing. Most forms have the capacity to

resprout from an underground woody stem (lignotuber) after

fire, drought or physical damage.

The stems have been much favoured for the building of

fences and other structures around domestic buildings, par-

ticularly in south and eastern Australia. A small domestic

brushwood fencing industry has been operating for several

decades using broombush material harvested from the wild.

However, as wild harvesting is restricted by conservation

authorities in Western Australia, South Australia and

Victoria, the expansion of the brushwood industry is con-

strained. The supply to WA of ready made fencing panels

and bundles of brushwood, has recently been supplement-

ed by wild harvest from western NSW, with small quantities

harvested from native stands on private property in WA.

The harvesting of broombush from natural stands is either

restricted or illegal in most Australian states. The long term

sustainability of the industry relies on the development of

broombush plantations that will complement and eventually

replace the wild harvesting. An increase in the available sup-

ply of broombush would provide opportunities to expand

local and export markets. 

Dryland salinity is an enormous economic, environmental

and social threat in the agricultural region of WA. Being a

long-lived perennial species, broombush plantations can

help to prevent or alleviate salinity, protect waterways, bol-

ster biodiversity in remnant vegetation and provide an

opportunity to diversify farm income 

SPECIES OVERVIEW

Broombush is a myrtaceous shrub belonging to a group of

species which comprise the 

Melaleuca uncinata complex.

Recent field work and taxonomic study of the 

Melaleuca

uncinata complex (Lepschi) has shown that the complex

includes at least eleven species. Observations have shown

that several species can co-occur at any given location in

the wild. Many of the species are capable of resprouting

(from lignotuber: a swollen woody stem at ground level) after

the aerial stems are removed by physical damage (such as

cutting), drought or fire. True 

M. uncinata occurs from near

Munglinup in WA, east to at least the Eyre Peninsula in SA.

In WA there are another ten closely related species.

However, not all of these species of broombush can be con-

sidered suitable for construction of brushwood fencing. 

The preferred material for brush fencing typically has long,

thin straight stems (at least 1300mm long) with a persist-

ent smooth, dark bark. Species with short, crooked stems

or papery bark are not as desirable. However, the conditions

under which the broombush species are grown will affect

the growth rate and form which may determine usefulness

for manufacture of brushwood fencing. In WA, the species

most useful for brushwood fencing are 

M. uncinata and two

forms of 

M. atroviridis, although the generally slower grow-

ing 

M. hamata (widespread), M. osullivanii (Swan coastal



plain) and 

M. concreta (northern wheatbelt) may also be

suitable. 

Investors seeking to grow broombush for commercial pur-

poses must ensure they have the best species for their spe-

cific site conditions. The origin of seed used by nurseries to

produce seedlings (or seed used for direct seeding) should

be verified as suitable. If in doubt, contact an industry rep-

resentative or your local Greening Australia (WA) or CALM

office.


COMMERCIAL PRODUCTS

The major commercial use for broombush is brushwood

fencing. The durability of brushwood fencing is highly

dependent on the quality of construction. Traditionally, in SA

and Victoria, bundles were cut from wild plants and trans-

ported to the cities where skilled tradesmen would con-

struct fences on site. This involved densely packing the

stems in a supporting frame of uprights and horizontal wires

that were neatly trimmed and capped with steel or brush-

wood. It is not uncommon, especially in rural areas to see

amateurishly constructed fences that sag, and have visible

gaps with stems falling out. In Western Australia, brush-

wood fencing can often be seen in some of the newer, more

exclusive residential developments.

As brushwood fence packing is not a traditional craft in WA,

the fences are usually constructed using panels, which have

been packed, wired and trimmed to consistent specification

in a factory. The panels are transported to the construction

site and erected on a sturdy concealed steel framework. 

Brushwood may also be used in gazebos, pergolas and

gates, and other decorative landscape structures.

SITE SELECTION

Sufficient experience already exists to suggest that

Melaleuca species can be commercially cultivated to pro-

duce brushwood fencing material. With good management

on favourable sites, brushwood should be profitable and

may provide opportunities for regional value adding.

Selecting species best suited to specific site conditions is

critical to the commercial viability of a broombush planta-

tion. Broombush species grow naturally in a wide range of

conditions from cracks in rocks, to shallow rocky soil on hill-

tops to deep mid-slope sands and the saline margins of

The opportunity exists to cultivate broombush (Melaleuca uncinata and related species) on cleared

agricultural land in southern WA, for the sustainable production of brushwood fencing material. Broombush

can be grown on land that is not highly productive for conventional agriculture, including sites that are

marginally saline and seasonally waterlogged. 

This information aims to provide an overview of suitable species, production and establishment techniques

and opportunities associated with producing broombush for brush fencing. 



drainage lines. Improved growth and commercial outcomes

will result from better growing conditions. It is important to

ensure adequate depth of soil for any broombush plantation

site.


Generally the preferred sites on previously cleared farmland

will be mid to lower slopes where there is a depth (at least

250 mm) of sand, sandy loam or gravely loam over clay with

run on of fresh water. Sandy and more transmissive soil

allows rapid penetration of rainfall through to the plant roots

and clay at a deeper level allows accumulation of moisture

at depth, which will be available to the deeper roots over

summer. Some species are tolerant to more saline condi-

tions, but higher levels of salinity will retard growth and

hence harvesting rotation will be longer. The fresher the run

on of water the better. Sites experiencing prolonged water-

logging should be avoided unless mounding can ameliorate

these conditions.

Broombush species grow naturally over a wide variation in

rainfall. Commercial broombush plantations are probably

best suited to 350 to 600 mm annual rainfall zones in

southern WA. Individual site characteristics (especially soil

depth), combined with annual rainfall, will determine growth

rates and time to commercial harvest.

SPECIES SELECTION

Mid slopes - duplex soil

Melaleuca uncinata is lignotuberous and grows naturally on

shallow red loams over granite and is one of the most desir-

able forms of broombush. It will grow well on mid slope

duplex soils, deeper loams and sandy loams as long as

there is plenty of fresh water run on and the soil is not less

than 300 mm. Shallow soils over granite can be very soggy

in winter, but will dry out over summer causing stress and

stunted growth or plant death. 

Deep sands

The lignotuberous form of 

Melaleuca atroviridis, grows high

in the landscape in the northern central wheatbelt, and is

ideally suited to deep, pale yellow, acidic sands 

Sandy flats along saline watercourses

The larger, upright form of 

Melaleuca atroviridis is wide-

spread through the central and southern wheatbelt, has

ideal stems for brushwood production and grows vigorously

on shallow sands adjacent to saline river courses. It is ide-

ally suited to the sandy margins of saline flats. Mounding

may be desirable to improve drainage and growth. It may

also grow on more saline soils but cannot be expected to

grow with comparable vigour. The tree form is non-ligno-

tuberous, but will sprout from the trunk if cut well above

ground level.

Swampy Coastal plain 

Melaleuca osullivanii is native to the coastal plain between

Perth and Busselton and is sometimes used as capping on

brushwood panels. It grows naturally on grey sands over clay

in seasonally waterlogged areas. As wild trees they may

have an unruly, straggly form but dense cultivation in ideal

conditions should produce commercial stems.

Other


Melaleuca hamata is a lignotuberous species which is wide-

spread across the wheat belt, occurring in a diverse range

of soil types from shallow rocky soil to clay and sandy clay

loams. In good conditions it may produce good stem form

for brushwood, although its growth rate may not match other

species. Considerable variation in plant form occurs

between different localities, necessitating care in selection

of seedlots for brushwood production. It may be used where

additional landcare objectives and the desire to use local

species may outweigh commercial growth rates.

M. concreta which grows from the the lower Murchison River

district southwards to the Cataby-Regans Ford district, can

also produce fine brushwood material if provided with suit-

able growing conditions. 

PLANTATION SIZE

A minimum of 5 hectares is suggested for a commercial

plantation.  This should ensure that the producer will have

a sufficient quantity of material (at least one semi trailer

truck load of 20 tonnes) at harvest to be useful to manu-

facturers, and that there will be a substantial investment

incentive to ensure good management. Bigger plantations,

100 hectares or over may allow sufficient annual turnover

from staggered planting and harvesting to constitute a

stand alone enterprise.

PLANTATION DESIGN

Broombush species are somewhat susceptible to grazing by

stock, particularly in the initial years of establishment.

Plantations should be fenced to avoid physical damage and

opportunistic grazing.  Broombush plantations will be better

suited to block type plantings, where specific soil types can

be targeted, and plantations easily fenced.  Wide belt plant-

ings, can be considered along creek lines or existing fence

lines.  Alley type systems may not be suitable, as extensive

fencing would be required if stock are to graze between the

alleys.

Consideration should be given to accessibility for harvesting



and maintenance operations. This includes a suitable net-

work of vehicle access lines, adequate firebreaks and suffi-

cient turning space for operations such as spraying. Very

steep or rocky sites may not be suitable.

Remnant Melaleuca concreta Wongan Hills, WA


ESTABLISHMENT

There are two main methods for establishing broombush;

nursery raised seedlings and direct seeding. Different site

preparation methods are required for each establishment

method. Direct seeding offers the potential for lower estab-

lishment costs, however reliable direct seeding methods for

broombush have not yet been proven. The most appropriate

method to use will depend on site conditions, available

equipment and finance and the acceptable level of risk to

the investor.

SITE PREPARATION

Individual site characteristics influence site preparation

methods. Heavy grazing and spray topping in the year prior

to establishment can be effective in reducing weed burden

and accumulating soil moisture for sites where seedlings or

direct seeding techniques are to be used.

Seedlings

For establishment using seedlings, planning is required to

ensure seed of suitable provenance is available to your pre-

ferred nursery. Nurseries will need to have seed by

November-early December to ensure suitably advanced

seedlings are available for the planting season in the fol-

lowing year (June - August). When planted, seedlings must

have a well developed root ball and ideally be at least

100mm tall.

Weed control in the year previous to planting will allow soil

moisture to accumulate.

On lighter textured soils, machine planting in a one pass

rip/scalp/plant operation is efficient and effective.

Scalping, where the surface layer of the soil containing weed

seed is mechanically removed, can provide effective weed

control in the year of planting. Alternatively, sites can be

rip/scalped and then hand planted. On sites prone to heavy

weed infestations, the application of a knockdown herbicide

2-4 weeks prior to scalping is recommended. However,

some weed cover between scalped lines may be desirable

on sites at risk of wind erosion.

On heavy textured soils, or sites prone to seasonal water-

logging, ripping and mounding is recommended. April is gen-

erally a suitable month to construct mounds, while the site

is relatively dry. Ensure that the mounding equipment

includes a roller to flatten lumps on the mound. A smooth,

flat surface will greatly improve chemical weed control.

Following the first weed germination (typically around late-

May), apply a knockdown/residual herbicide mix. A mixture

of glyphosate and simazine (at recommended rates) has

been found to be highly effective for controlling a wide range

of weed species on many sites. A second knockdown herbi-

cide treatment may be required just prior to planting if addi-

tional weed germination occurs. Care must be taken when

planting into ground previously sprayed with pre-emergent

herbicide as soil moisture and level of organic matter will

determine location and activity of the chemical.

Aim to plant seedlings between late June and early August.

Upland, free draining sites are suited to earlier planting,

while seasonally wet sites can be planted later in the year.

Ensure that nursery seedlings comply with recommended

quality specifications and are healthy and well-watered

immediately prior to planting. It is advisable to ensure that

the moisture filled root ball is planted at least 20mm below

ground level.

Planting design 

Optimal seedling densities for the production of brush fenc-

ing material have not been fully researched. High stocking

densities will encourage more upright growth, whilst lower

stocking densities on less favourable sites will allow max-

imisation of individual plant height. For establishment using

seedlings,

the economic attractiveness of planting

seedlings will diminish substantially as stocking density is

increased.

A target establishment density of 2,000 to 5,000 plants per

hectare is recommended to achieve a workable compromise

between growth rates, plant form and establishment costs.

It is possible that stocking densities could be increased fur-

ther on prime sites, however the increased seedlings costs

may offset any productivity gains. Establishment costs using

seedlings, inclusive of all required operations, are typically

in the range of 50c-80c per planted seedling.

To achieve a stocking density of 5,000 stems per hectare,

plantations can be established with rows 4 metres apart,

and seedlings 500mm apart within the rows. At this densi-

ty, the planted cost will be between $2500 and $4000 per

hectare.


Direct seeding 

Direct seeding offers scope for the establishment of high

density broombush plantings at relatively low cost. However,

fine seeded species such as broombush have proven to be

difficult to establish reliably using conventional direct seed-

ing methods. Improved methods are being actively investi-

gated.

Three year old brushwood plantation, Central Wheatbelt



Melaleuca atroviridis seedling plantation at 5000 per hectare

A typical seeding rate for broombush is approximately 0.5

kg of seed per hectare. Unselected seed generally costs

between $400 and $600 per kg. Specially selected seed

may cost over $1000 per kg. Therefore, if seeding at 0.5 kg

per hectare, seed will cost up to $500 per hectare.  Higher

seeding rates can be used, which is still cheaper than buy-

ing nursery grown seedlings. 

Some soil types and sites will be more suited to direct seed-

ing than others. Direct seeding will be less effective in fine

textured, dry soils, which can blow away with the seed or be

blown over and bury germinating seedlings. Sites with

uncontrolled heavy weed burden should not be considered

for direct seeding and deeper sandy sites may dry out too

fast for young seedlings to establish.

Direct seeding is most likely to succeed in weed free sites

where the soil is well structured with larger particle size,

which can hold seed in place, retain moisture and will not

blow.


Direct seeding should be conducted using purpose built

equipment which seeds into a scalped bed from which the

topsoil and associated weed seed bank has been removed

by a scalping blade. A number of direct seeding machines,

designed to be towed by a medium sized tractor, are avail-

able for purchase or hire in WA. Press wheels are important

to provide good soil to seed contact. Residual herbicides

should be used with great care if sprayed in the year of

establishment. Soils with high organic matter that lock the

pre-emergent near the surface can be scalped off.

Seedlings emerging from direct seeding can be susceptible

to attack by redlegged earth mites, insects or vertebrate

pests. Regular monitoring is warranted to provide early

detection of pest activity. Control measures, such as the

application of registered insecticides, may be required.

Successful direct seeding can result in many seedlings ger-

minating per metre of rip line in spring, and establishment

of at least 10,000 per hectare. An ideal direct seeding

result would provide at least two plants per metre of rip line

(evenly distributed) at age one year. Row spacing at this den-

sity will determine overall plants per hectare. If insufficient

seedlings establish, nursery seedling planting may be

required in the second year to achieve stocking densities.

Second Year Weed Control

The growth of broombush will be improved if weeds are con-

trolled in the second year of establishment. This can be

achieved by spraying between rows with a Simazine based

residual herbicide at the break of season. If some weeds

have already emerged, a low rate (<250g per hectare active

ingredient) of a Glyphosate based herbicide can be added to

the inter row spray application.

A number of other selective herbicides may be suitable for

the control of specific problem weeds. 

POTENTIAL YIELDS

The number of plants per hectare, management, time to

first harvest and site conditions will determine the yield.

Observations in trial plantations and revegetation in WA indi-

cate variation in potential yields, but time to first harvest is

expected to be about five years. One private brushwood

fence building company promoting plantation establish-

ment, estimates 30 tonnes per hectare of brush is achiev-

able at the first harvest. However, bigger plants in roadside

revegetation have produced 25 kg each, which at a low den-

sity of 1000 per ha would produce 25 tonne/ha.

The prospectus of a private investment company's brush-

wood project forecasts a yield of 6 kg of brush material per

plant at first harvest at age five years, which equates to 48

tonnes per hectare. This estimate was made from extensive

sampling of established brushwood in the northern wheat-

belt.


Brushwood, when bundled, may wholesale on current mar-

kets for between $120 and $300 per tonne, which results

in a gross return of between $3,000 and $7,500 per

hectare at first harvest for a mid range yield of 25 tonnes

per hectare. The price paid per bundle will depend on the

quality of the brush in terms of the stem length, thickness,

degree of branching, leafiness, nature of the bark and cur-

rent market demand. 

The time between the first and the second harvest may be

shorter, due to the plants having an established lignotuber

and root system, but will depend on annual rainfall as

stored groundwater will have been used by the growth to ini-

tial harvest. To date, the ability of different broombush

species to resprout under a regular harvesting regime has

not been well researched. 

Eight month old direct seeded Melaleuca hamata

Bundles of wild harvested broombush


HARVESTING TECHNIQUES

Broombush is traditionally harvested by hand using a

machete or shoulder mounted mechanical brushcutter and

then bound in bundles of 25kg to 35 kg. The establishment

of bigger plantations could facilitate the development of

mechanical harvesting and bulk handling of brushwood. 

Harvesting should be carried out when there is sufficient

soil moisture to sustain resprouting, such as late winter or

early spring. Late autumn harvesting may also be consid-

ered but resprouting may be slow through winter. Harvesting

in summer may result in drought deaths.

MAINTENANCE

To ensure survival of plantations after establishment, own-

ers need to ensure that they are adequately protected from

fire by careful site planning and establishment and mainte-

nance of firebreaks. It may be practical to spread larger

plantings into smaller discrete plantings to protect from the

potential of total loss to fire. A minimum firebreak of 20

metres of bare earth should be considered between block

plantings of five hectares. Local authorities and fire servic-

es can also advise on firebreak requirements.

Leaf chewing insects, such as spring beetles, are another

potential hazard capable of reducing plant productivity.

Insecticide treatments may be required for sites that are

repeatedly attacked. 

REGIONAL VALUE ADDING

The profitability of broombush will be affected by distance

from markets.  Unprocessed brush material has a low bulk

density, which makes it poorly suited to efficient, low cost

transportation. The prospect of value adding close to the

plantations may be attractive and feasible. Most broombush

sold in WA today is marketed as ready made panels which

could be constructed in regional factories and transported

as a much higher value end-product.

Some commercial panels are 1.8x 2.2 metres and require

about 100 kg. Assuming a yield of 25 tonnes per hectare of

brush produced in 5 years, this could be value added to 250

new panels. If each panel retails for around $125, a retail

value of $31,250 per hectare after five years could be

achieved.

Government control Regulation

In WA, the Department of Conservation and Land

Management is responsible for protecting and conserving

the natural flora and through its Wildlife Protection Branch

ensures that any commercial harvesting of native species is

conducted in a sustainable manner. Currently the depart-

ment is not issuing licences to harvest broombush from

crown land due to concerns of overcutting and limited abili-

ty of natural stands to recover after harvesting. Harvesting

from wild plants on private land is technically possible; how-

ever harvested material cannot be sold without licence from

the Department of Conservation and Land Management.

Licences to harvest from wild plants on private land will not

be issued without inspection to determine if the proposed

harvest area is likely to recover. Currently there is very little

broombush supplied from private land in WA.

A licence to harvest broombush cultivated on private land

(previously cleared farmland) is obtainable from the

Department of Conservation and Land Management.

Landholders and investors considering growing broombush

for sale should discuss the matter of licencing for harvest

and sale with their local Conservation and Land

Management office.

Current Commercial Planting

In recent years in WA a broombush industry based on culti-

vated plantations has begun to develop. Brushwood

Australia, a company based in Jandakot and involved in the

manufacture and construction of brushwood fences, has

been actively involved in promoting cultivation of broombush

to wheatbelt landowners. The Rewards Group Limited,

based in West Perth, has raised prospectus capital and

established commercial plantings on behalf of investors in

the central wheatbelt. There are also numerous small pri-

vate plantings. Some revegetation consultants can supply

broombush seed and direction on establishment and broom-

bush form selection.

ACKNOWLEDGEMENTS

Thanks


 

Daniel Huxtable from the Department of Conservation 

and Land Management Revegetation Systems Unit - for 

providing useful information on all aspects of the indus

try;

 

Stephen Darley of Brushwood Australia - for providing 



valuable information on form selection, harvesting, pro

cessing and fence construction; 

 

Geoff Cockerton of Landcare Services - who was a great



source of practical information on plantation establish

ment and the brushwood industry; and

 

Wayne O'Sullivan - who gave freely of his knowledge of 



the many species which make up the broombush com

plex.


References

Brushwood Australia. Brushwood Fencing. Kwinana, 2001.

Bulman, P, P Beale and A Knight. "Growing Broombush for 

profit and land protection" Bulletin Jan 1998 

Primary Industries and sources. South Australia,

1998.


Forest Rewards Ltd. Brushwood Project 2001. West Perth,

2001.


Lepschi, Brendan and Lyn Craven. Field work and taxonom

ic study of Melaleuca uncinata complex. Centre for

Plant Biodiversity Research, Commonwealth 

Government, Canberra, 2004. 

Contacts

Chris Robinson

Greening Australia (WA) Albany Office 

08) 9892 8486

Tim Emmott

Greening Australia (WA) Northam Office 

(08) 962 12400

Disclaimer

This information is provided in good faith, and was consid-

ered correct at time of printing. 

Greening Australia (WA) recommends that readers carefully

evaluate the accuracy, currency, completeness and rele-

vance of the material in this document for their purposes.

This document is not a substitute for independent profes-

sional advice and readers should obtain any appropriate pro-

fessional advice relevant to their particular circumstances.




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