Fact Sheet

FS 04/02

Windbreaks for the Upper South East PDF (277kb)

Introduction

Well-designed windbreaks can benefit every farm. They can be used to:

• protect crops and pastures from drying or damaging winds,
• protect livestock from cold winds,
• help to prevent soil erosion,
• protect living and working areas from strong winds,
• provide posts, firewood, timber, fodder, honey and other products,
• provide habitat for wildlife,
• act as firebreaks by slowing the rate of fire spread.

A windbreak of trees and shrubs works by filtering and breaking the force of the wind. Permeable windbreaks that let some wind pass through are most suitable. The slight movement of air through the windbreak forms a cushion of slow-moving air on both sides of the windbreak (see diagram).

Location

For best results, plant windbreaks at right angles to the winds from which protection is needed. These are not necessarily the prevailing winds. Crops are often worst affected by hot, drying winds from the north. Livestock are at greatest risk from cold winds and rain which come from the south or south-west.

To keep costs down, establish windbreaks against existing fence lines where possible, but consider the best location to match land capability boundaries. If practical, a good location for a windbreak is high in the landscape (e.g. along a ridge line) as a greater area in the lee is protected from wind. Take care to avoid planting close to windmills and do not plant under power lines.

Height

The windbreak height determines the size of the sheltered area. The taller the trees in the windbreak, the greater the area it protects. As a guide windbreaks are most effective for a distance of 12 to 15 times the height of the tallest trees, and protection of crops has been observed up to 25 times the height.

Length and gaps

Wind is deflected around the ends of windbreaks. The deflected wind can accelerate around the end of the belt causing localised crop damage. For this reason windbreaks should be long continuous lines of trees and shrubs to minimise any end effects. Gaps within the windbreak can have the same effect so where these are essential, for example where a gate is needed, the gap should be angled at 45 0 to prevent the wind from accelerating through the space.

Number of rows

Windbreaks incorporating both trees and shrubs in three to six rows are effective for most farm situations. Multiple-row windbreaks are less affected by gaps caused by missing trees than single row windbreaks. Where land is limited, a staggered two-row design of tall trees and lower shrubs should be used for the best shelter effect. Single-row windbreaks should only be used where land is so valuable that only a small amount of space can be spared for tree planting - for example, on high-value horticultural land. When only one row of trees can be planted, try to use trees that have foliage from the ground up if possible. Belts, with trees only, can be established for wood production, but they may be less effective in providing low shelter for animals.

Row and plant spacing

The distance between plants in windbreaks is based on the size of suitable plants for the local climate and soils (see Appendix 1). It is also important to allow access for tractors and machinery for weed control and maintenance. Use the spacings in the diagram as a guide.

Tree spacing guide showing layout dimensions for a three row windbreak.

These may change depending on species chosen or if more rows are added.

Establishment techniques

Direct seeding is a method using a specialised machine to sow a mixture of native seed straight into the ground. It is very quick, low-labour and low-cost. Recommended for all soils except heavy cracking clays where tubestock seedlings are preferred. Local nurseries and contractors specialising in farm trees include:

• SE Direct Seeding Service (Josie and Jamie Jackson), Willalooka, 8757 8276
• Eucaleuca Native Services (Ralph Scheel), Thomsons Rd, Naracoorte, 8762 2061
• Reedy Creek Nursery (wholesale), Mike Quarmby, Princes Hwy, near Kingston, 8768 7220
• State Flora, Murray Bridge wholesale outlet ( Bremer Road) , 8539 2100.
• Greening Australia (statewide), 8372 0100
• Trees For Life (statewide), 8406 0500 (seedlings grown by volunteers are available to members at minimum administrative cost through the ‘Tree Scheme’).

Site preparation

Weed control. Many areas in the Upper South East where landholders wish to establish windbreaks carry pastures and weeds that compete strongly with new seedlings for moisture and light. To be successful with revegetation, you must get rid of all existing pasture and weeds well in advance of planting seedlings or direct seeding. Particular attention should be given to perennials such as sorrel, veldt grass, primrose, couch grass, kikuyu, lucerne, bracken and phalaris. This is usually achieved by spraying out the site with broad-spectrum knockdown herbicides such as glyphosate several times before planting or seeding.

Aim to start weed control 12 months before planting. Start in late winter or early spring and again in summer (depending on weeds present). Spray next after the following break of season and again just prior to planting if a new flush of germination has occurred. Residual herbicides (eg Oust ®, Ally ®, Goal ®, simazine) can be used for more effective weed control but they can harm seedlings if not used appropriately (note that some are not registered for use with natives).

Weed control should be carried out again in the year after planting/seeding. This can be done with shielded sprays but special over-spray mixtures can also be used.

Seek advice from revegetation consultants or contractors prior to using residual chemicals or over-sprays.

Ripping to allow better root penetration should be considered if limestone or a clay hardpan is within 10 to 15cm of the soil surface. Rip-lines in clay soils can tend to open up later in summer so only rip if absolutely necessary. For heavy soils, rip in summer or early autumn when soils are dry so that the ripper shatters the soil rather than slices through it. Slicing glazes the soil surface and prevents lateral root penetration. On the other hand, rip non-wetting sands (if needed for planting tools) only if moist for best results.

Ripping should be at least 50cm deep if possible. Use a concrete roller (at least 60 cm wide) over the rip line afterwards to help crush rocks, remove air pockets and settle the soil. Avoid rolling with narrow tractor tyres as this can cause compaction and guttering. Where planting or spraying machinery is to be used, any large rock pieces brought to the surface by ripping should be removed if they cannot be crushed.

Mounding of the soil to 50cm high and 50cm wide can help plant survival in waterlogged and saline areas. Bear in mind though that the surface of mounds will dry out quicker in summer so this technique should only be used in very wet areas. When mounding in long rows, consider leaving breaks every now and then to allow for natural water flows.

Protection

It is usually best to keep windbreaks permanently fenced to prevent gaps being created by livestock browsing on the lower limbs of established trees and shrubs. Fencing may not be required in situations of continuous cropping; in timber belts with trees only, which are not likely to suffer bark damage from stock; or in some alley farming situations with fodder shrubs where stock grazing of the windbreak is expected.

Financial assistance

Financial assistance maybe available through the Natural Heritage Trust Envirofund. Contact South East Natural Resource Management Board, Community Landcare Coordinator (8724 6033) for details.

You maybe able to claim a tax deduction in the year you incur capital expenditure on landcare measures for land in Australia provided you incur it "erecting fences to keep out livestock or vermin from areas affected by land degradation to prevent or limit further damage and assist in reclaiming the areas" or "erecting fences to separate different land classes in accordance with an approved land management plan" (ATO, Information for Primary Producers). A recoupment of the deductible expenditure is assessable under Subdivision 20-A of the Income Tax Assessment Act 1997 (ITAA 1997). Contact the Australian Taxation Office or your taxation adviser for an information pack for primary producers.

Further information:

PIRSA Rural Solutions Environmental Consultants: Struan Office 8762 9100.

Useful references:

• Windbreaks, Steven Burke, 1998, Inkata Press, Port Melbourne, Vic.
• Direct Seeding of Trees and Shrubs, Greg Dalton, 1993, Primary Industries (SA), Government Printer Adelaide.
• What Seed Is That?, 2003 2 nd Edition, Neville Bonney, PO Box 37 Tantanoola SA 5280.
• Native Trees and Shrubs of South Eastern Australia, L. Costermans, (1992 revised edition) Weldon Publishing, Sydney. Contains photographs and descriptions.

Last update: February, 2008.

Acknowledgments: Based on a fact sheet originally prepared by Jim Burston.

Agdex: 301/31

Author: Peter Tucker and Zita Stokes, Environmental Consultants, Struan.

Appendix 1: Species selection

When selecting species for a windbreak firstly consider what your goals are. Apart from shelter, if you wish to enhance wildlife habitat, choose a diverse range of local native species. If you wish the belt to also provide products, you will need to seek specialist advice about species suitable for timber, firewood, pollen for honey, seeds etc. Ultimately the species chosen, whether native or exotic, need to suit the soil type and climatic conditions of the site. The following soil type information and species table will help give an indication of some species suitable for windbreaks in the Upper South East.

Soil type is a very important consideration when planting trees. Some species will survive well on waterlogged clays, others will only thrive in well-drained sands. Choosing the wrong species for a soil type can end in poor growth and premature deaths. The table on the following pages shows native plant species which are suitable for windbreaks on eight major soil types found in the Upper South East region (defined here as the areas north of Kingston - Lucindale - Padthaway – Kybybolite up to the Coorong District Council area).

Major soil types (Upper South East)

• Heavy clay (grey-black, self mulching)

A uniform clay profile, being very sticky when wet. The surface soil is self-mulching and the pH is alkaline. In uncultivated areas, gilgai are common (e.g. Wolseley district).

• Sand over clay (leached siliceous sands)

A variable depth of sand over clay, ranging from 10 to 100cm, usually on flats. Soil pH is generally acidic and has a moderate water holding capacity. The upper 10 to 20cm is coloured grey-brown by organic matter.

• Red brown earths

Generally found in Bordertown/Wolseley/Mundulla region, these soils have a brown sandy-loam to loam surface texture, which sets hard when dry. Good water holding capacity. Soil pH is generally neutral to slightly acidic.

• Deep sands

Sandy range country with undulating to rising terrain. Accumulation of organic matter at surface. The sands have a low water-holding capacity, low soil fertility, often non-wetting and the pH is mildly acidic.

• Sand or loamy sand over limestone

Typical of old inland ranges where dune limestone underlies a shallow sandy topsoil. The sand can be grey or brownish to white depending on organic matter.

• Loam over limestone

For example in the Keith/Culburra/Coonalpyn area; these soils are typically shallow, grey or brown in colour, and hard setting when dry. Frequent limestone outcrops and/or free limestone in the topsoil. Soil pH is generally neutral to alkaline.

• Red soils (Terra Rossa)

A red-brown soil (varying from sandy- to clay-loam) overlying limestone. Soil depth is shallow, with frequent limestone outcrops. Soil pH is generally neutral to slightly acidic in the surface but neutral to alkaline above the limestone.

• Calcareous coastal sands

Deep, pale yellow loose coastal sand consisting mainly of fragments of marine shells. The upper 20 to 30cm is coloured grey-brown by organic matter. The soils are generally alkaline and have a low water holding capacity.

Trees and shrubs suited to windbreaks in the Upper South East

Note: this list is only a guide. If you are seeking species local to your particular area, talk to a revegetation consultant. Remember: a windbreak works best if using a mixture of trees and shrubs. Do not rely on only trees if they shed lower limbs as they mature. Height is that at maturity (range depends on site conditions); Rainfall is that for best survival/growth; Waterlogging tolerance – more ticks = better survival at sites that become waterlogged. Asterisk * = generally not suited to large-scale direct seeding either due to lack of available seed or problems with germination times. Soil types explained in text prior page.

Botanic name	Common name	Form	Height (m)	Rainfall (mm)	Water logging tolerance	Special notes	Soil type suitability
							1	2	3	4	5	6	7	8
Acacia brachybotrya	Grey Mulga	Medium shrub	1-3	250-500			√	√	√			√		√
Acacia calamifolia	Wallowa	Medium shrub	2-4	200-700	√			√	√	√		√
Acacia cupularis	Coastal Umbrella Bush	Small shrub	1-2	350-700	√	Fast growing		√	√		√	√	√	√
Acacia farinosa	Mealy Wattle	Small shrub	1-2	300-600				√	√			√
Acacia hakeoides	Hakea Wattle	Medium shrub	1-4	250-500					√			√
Acacia halliana	Hall's Inland Wattle	Small shrub	1-2.5	250-400		Spreads 4-5 m wide			√			√	√
Acacia leiophylla	Limestone Wattle	Medium shrub	1-2.5	500-800							√		√	√
Acacia mearnsii	Black Wattle	Medium tree	7-10	>600		Padthaway area; fast growing		√
Acacia melanoxylon	Blackwood	Medium tree	8-15	>550	√	Native in southerly areas		√
Acacia microcarpa	Manna Wattle	Small shrub	1-3	250-600			√	√	√			√
Acacia myrtifolia	Myrtle Wattle	Small shrub	1-2	>500				√	√	√	√	√	√	√
Acacia paradoxa	Prickly Acacia or Kangaroo Thorn	Medium shrub	2-3	>300		Fast growing; may be invasive; provides good protective habitat for small native birds	√	√	√		√	√	√	√
Acacia pycnantha	Golden Wattle	Medium tree	4-8	>350		Fast growing; national floral emblem		√	√	√	√	√	√	√
Acacia rigens	Needle Bush Wattle	Shrub	2-3	200-300					√			√	√
Acacia rupicola	Rock Wattle	Shrub	1-2.5	300-800				√	√		√	√	√
Adriana klotzschii	Coastal Bitter Bush	Shrub	1-2	>300		Coastal plant					√			√
Allocasuarina leuhmannii	Buloke, Bull Oak	Medium-tall tree	7-15	450-650	√√√	Found on clays near Vic border; food source for red-tailed black cockatoo; suckers	√		√
Allocasuarina mackliniana	Macklin's She-oak	Small shrub	1-2	400-600				√		√	√
Allocasuarina muelleriana	Slaty She-oak	Medium shrub	2-4	350-600				√		√	√
Allocasuarina paludosa	Scrub / Swamp She-oak	Medium shrub	2-3	>500	√ √			√
Allocasuarina pusilla	Dwarf She-oak	Small shrub	1-1.5	350-750				√		√	√		√

Allocasuarina verticillata

Drooping She-oak

Medium tree

5-8

>350

√

Excellent for firewood

√

√

√

√

√

√

Atriplex cinerea

Coast Saltbush

Small shrub

1-1.5

350-700

√

OK for moderately saline sites; found naturally on coasts, sandy shore lines

√

Baeckea behrii

Short-leaved Broombush

Small shrub

1-2

300-500

√

√

√

Banksia marginata*

Silver Banksia

Small-tall shrub

2-5

>400

√

Flowers abundant in nectar provide good food source for wildlife; small on poor sands, tall on fertile loams

√

√

√

√

√

√

Banksia ornata*

Desert Banksia

Medium shrub

1-3

400-650

Flowers abundant in nectar provide good food source for wildlife

√

Bursaria spinosa*

Christmas Bush

Medium-tall shrub

2-5

>300

Slow growing; germinates in cold months

√

√

√

√

√

√

Callistemon rugulosus

Scarlet Bottlebrush

Medium shrub

2-4

450-700

√√√

Prefers damp areas; flowers rich in nectar are food source for birds

√

Callitris gracilis

Native Pine

Medium tree

5-15

350-450

Slow growing

√

Callitris verrucosa

Scrub Pine

Small tree

2-5

250-400

Slow growing

√

Calytrix tetragona*

Fringe Myrtle

Small shrub

0.5-2

>400

Showy pink to purple flowers

√

√

Casuarina glauca (native to NSW & QLD only)

Swamp Oak

Medium tree

10-15

>350

√√√

Caution: weed potential, suckers freely; use on saline sites only

√

√

Casuarina obesa (native to WA only)

WA Swamp oak

Medium tree

10-15

>350

√√√

Non-suckering unless disturbed, use on saline sites only

√

√

Dodonaea viscosa spatulata

Sticky Hopbush

Medium shrub

2-4

>450

√

√

√

√

√

√

Eucalyptus arenacea

Sand Stringybark

Small tree

3-6

400-650

Hardy on poorest sands

√

√

Eucalyptus baxteri

Brown Stringybark

Medium tree

10-15

>500

Hardy on poor sands

√

√

Eucalyptus behriana

Broad-leaved Mallee Box

Medium tree

8-12

400-550

√

√

√

√

Eucalyptus camaldulensis

Red Gum

Tall tree

15-25

500-750

√√√

Good timber, firewood, habitat

√

√

√

Eucalyptus diversifolia

Coastal White Mallee

Small-medium tree

5-15

350-750

Hardy coastal tree; excellent for well-drained soils with limestone

√

√

√

√

Eucalyptus dumosa

White Mallee

Medium tree

5-8

300-650

√

√

Eucalyptus fasciculosa

Hill or Pink Gum

Medium tree

10-15

450-750

Excellent for firewood

√

√

√

√

√

√

Eucalyptus gracilis

Yorrell

Small tree

4-7

250-450

√

√

√

Eucalyptus incrassata

Ridge-fruited Mallee

Small tree

4-8

350-550

√

Eucalyptus largiflorens

River or Black Box

Medium-tall tree

6-15

350-550

Usually close to watercourses

√

√

Eucalyptus leptophylla

Narrow-leaved Red Mallee

Small tree

2-6

200-550

√

√

√

√

Eucalyptus leucoxylon megalocarpa

Large Fruited SA Blue Gum

Medium tree

6-10

450-800

√

Rounded shrubby coastal form

√

√

Eucalyptus leucoxylon pruinosa

Inland SA Blue Gum

Medium-tall tree

8-17

450-650

√

Blue-leaved inland form

√

√

√

√

√

√

Eucalyptus leucoxylon stephaniae

Scrubby Blue Gum

Small tree

4-15

450-650

√

Northern form

√

√

√

√

√

√

Eucalyptus microcarpa

Grey Box

Medium-tall tree

10-20

500-600

√√

Found close to Victorian border

√

√

Eucalytpus occidentalis (native to WA)

Flat-topped Yate

medium-tall tree

10-20

>350

√√

Caution: may be short-lived; use only on saline sites; firewood/timber

√

√

Eucalyptus odorata

Peppermint Box

Medium tree

4-16

350-500

Mainly found around Bordertown

√

√

√

√

Eucalyptus oleosa

Red Mallee

Small tree

5-8

300-450

Valued for honey production

√

√

√

√

Eucalyptus porosa

Mallee Box

Medium tree

5-10

300-500

√

√

√

√

Eucalyptus socialis

Summer Red Mallee

Small tree

5-10

250-450

√

√

√

√

Eucalyptus viminalis cygnetensis

Rough-barked Manna Gum

Medium tree

10-15

>450

√

Preferred koala food

√

√

√

√

√

Goodia lotifolia

Golden Tip

Medium shrub

1-3

550-700

√

√

Hakea muelleriana*

Desert Hakea

Medium shrub

1-3

350-500

√

√

√

Hakea nodosa*

Yellow Hakea

Medium shrub

2-3

>550

√√

√

Hakea rostrata*

Beaked Hakea

Small shrub

1-2

>500

√

√

Hakea rugosa*

Dwarf Hakea

Small shrub

1-2

350-700

√

√

√

√

√

Leptospermum continentale

Prickly Tea Tree

Small shrub

1-3

>500

√√

Prefers damp locations

√

Leptospermum coriaceum

Green Tea Tree

Medium shrub

2-3

350-500

√

√

√

Leptospermum lanigerum

Silky or Woolly Tea Tree

Medium-tall shrub

2-4

>600

√√√

Best near natural (fresh) soaks; found mainly near Kingston area

√

√

Leptospermum myrsinoides*

Heath Tea Tree

Small shrub

0.5-2.5

>450

√

√

Leucophyta brownii*

Cushion Bush

Small shrub

0.5-1

400-700

OK for moderately saline sites

√

Leucopogon parviflorus*

Coast Beard-heath

Medium shrub

2-3

>500

Fruits edible when ripe

√

Melaleuca acuminata

Mallee Honey Myrtle

Medium-tall shrub

2-4

400-550

√

√

√

√

Melaleuca brevifolia

Dwarf Salt Honey-myrtle

Medium shrub

2-3

250-700

√√√

Good for mildly saline and swampy sites; slow growing

√

√

√

Melaleuca decussata

Cross-leaved Honey-myrtle

Small shrub

1-3

450-600

√√

Flowers pink-mauve; prefers damp areas

√

Melaleuca halmaturorum

Salt Paperbark

Tall shrub

3-8

>350

√√√

Excellent for very saline and swampy sites; slow growing

√

√

Melaleuca lanceolata

Moonah / Dryland Tea Tree

Medium tree

5-10

>250

√

Slow growing; good on limestone

√

√

√

√

√

√

Melaleuca uncinata

Broombush

Medium shrub

1-3

350-650

√

Good for mildly saline sites

√

√

√

√

√

Melaleuca wilsonii

Violet Honey Myrtle

Medium shrub

1-2

500-600

√√

Mauve flowers; prefers damp sites

√

√

√

Pittosporum phylliraeoides

Native Apricot

Small tree

5-7

250-450

√

√

√

√

√

Xanthorrhoea caespitosa

Yacca

Small shrub

1-2

>350

Slow growing

√

√

√

√

√

Disclaimer

Use of the information in this Fact Sheet is at your own risk.  The Department of Primary Industries and Resources and its employees do not warrant or make any representation regarding the use, or results of the use, of the information contained herein in terms of its suitability, correctness, accuracy, reliability, currency or otherwise.  The entire risk of the implementation of the information which has been provided to you is assumed by you.  All liability or responsibility to any person using the information is expressly disclaimed by the Department of Primary Industries and Resources and its employees.

Windbreaks for the Upper South East

ISSN 1323-0409