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The GREEN HORSE - sustainable horsekeeping

APRIL/MAY 2007
Vol 28-6

In the Current Issue of The Green Horse you will find the following articles:

Information Exchange -
Reader's Tips, Views and Questions
Weed Control - It's all in the timing.
Things To Do .... Autumn
Electric Fence Safety
Growing Equine Herbs - Boneset by Fiona Adams
Deeds, Steeds and Weeds Weed Watch - St Johns Wort by Nicola Field
Enviro Fund Grants Pasture Renovation - Part One by Chris Ferriera and Tracey Bell
Horse SA Project

THINGS TO DO.... AUTUMN

We have had many requests for a seasonal planning calendar, and although we have not as yet been able to do this on a large scale, we have put together a quick checklist for Autumn.

Before the opening rains:

1. Make plans for the coming season in weed control, fertiliser and liming strategies, pasture improvement and stock grazing management. Pre-book your contractor (if not doing yourself) and purchase supplies of seed /fertiliser etc.

2. Graze to reduce dry residues, but keep groundcover above 70 percent, be prepared to yard stock if necessary to prevent overgrazing.

3. Regularly check dams for salinity, algal blooms or low levels when stock may become caught in silt or mud.

4. Control feral animals such as rabbits and foxes - seek advice from your local Agriculture Protection Board officer or attend a workshop.

After the break of the season:

1. Begin pasture sowing or cropping and fertiliser application.

2. Plant shrubs and trees while the ground is still warm.

3. Watch for insect attack in pastures, particularly red-legged earth mite and lucerne flea and be ready to spray if necessary.

4. Prepare for early control of broadleaf weeds by spraying when these plants are small to allow for cheaper and more effective control. This will save time and money.

ELECTRIC FENCE SAFETY

Regardless of the fact that electric fences are a simple and easy way to fence your property, there is a need for safety awareness when around them. While the number of human fatalities associated with livestock electric fences is low, it is important for horse property owners, armers and members of the public to recognise that contact with an electric fence can result in tragedy.

In most cases, such contact results in a relatively harmless shock, and usually the force of the first shock triggers awareness of the electric fence so that contact is broken and other shocks do not follow. However, there is a risk of serious injury or even death if someone receives multiple shocks over a long period (minutes to hours rather than seconds).

Entrapment and being rendered unconscious while in contact with an electric fence are two situations that can cause have serious outcomes. Physical entrapment can occur if you become entangled in the fence (electrified barbed wires pose a higher risk of this and must not be used), or are trapped between an electric wire and a physical barrier such as a water trough, a building or another part of the fence. A heart abnormality and/or pacemaker can make you more susceptible to being rendered unconscious from contact with an electric fence. There is an increased risk if your head or neck touches an electrified wire. Climbing through or under an electric fence can increase the danger of a shock to the head. If you need to get to the other side of a live electric fence you should either climb over it or find another away around it.

Children and Pets
An electric fence energiser should always be treated with respect - it can deliver a very powerful shock which may be harmful to children or pets under certain conditions. Never use electric fencing where it is likely to be touched by children or infants. This applies especially near swimming pools or dams where they are likely to be on wet ground with bare feet. A young child may become confused/disoriented when touching or climbing the fence, and not be able to physically get away from the fence.

Warning Signs
It’s important that you have adequate warning signs provided where there is public access. Electric fences bordering public thoroughfares are required to have a warning sign (G6021) at least every 20 metres. Signs should generally be at least 200 millimetres x 100 millimetres. The inscription on the sign should take the form of either the symbol below, or the words ‘ELECTRIC FENCE’ in lettering of at least 25 millimetres in height. It is recommended that the basic colour of the sign be yellow with black inscription, a highly visible standard colour the world over.

Energisers
All mains operated energisers must conform to local standard requirements. Energisers should, if possible, be installed inside a building in a position free from the risk of mechanical damage. If mounted outdoors, they should be mounted on a substantial structure in a position out of harms way. Each electric fence energiser should be fitted with a separate earth electrode and this should not be connected to any other earthing device, neither should more than one energiser be connected to the same fence. Never use any part of your household wiring or plumbing as an earth for your electric fence, as you risk directing the current into your home. Turning on the water tap could give you a nasty shock! Always use insulated cable when connecting a ground system to the energiser to ensure that no wires come into contact with sheds etc. which can also lead to electric shock.

Electric Powerlines
Crossings with overhead power lines should be avoided wherever possible. If such a crossing cannot be avoided, it should be made underneath the power line, and as nearly as possible at right angles to it. If an electric fence has to be installed in the vicinity of an overhead power line, the vertical distance between any fence wire or connecting lead and the surface of the earth should not exceed two metres. Do not attach an energiser or electrified wires to any post of any overhead power line unless authorised to do so. Fence wiring should be installed so that it is also well away from any telephone or telegraph line or radio aerial.

Fire Warnings
A faulty electric fence can produce a spark, so keep combustible materials away from fences. This includes dry matter such as leaves, weeds or dry branches. In fire prone areas, power the fence from the reduced power terminal or turn the energiser off on days of extreme fire danger.
Lightning strikes during thunderstorms are common and can cause serious damage. You may have kilometres of carefully insulated fence wires on your property, which, if hit, will conduct the electricity straight back to your energiser. Apart from the obvious fire risk, this will certainly damage or destroy the energiser. As with household appliances, you should disconnect the energiser from the fence, and unplug it from the power source for protection during electrical storms.
Always seek Local Body approval and advice before constructing any electric fence system near roadways, stock routes, railways etc.

Further information
Further information can be found in the Australian Standard AS/NZS 3014:2003 Electrical installations – Electric fences which sets out the requirements for constructing, installing and operating electric fences and for connecting them to associated equipment. The Standard covers electric fences powered by energisers supplied from all types of electric power sources such as batteries, solar cells, diesel or petrol generators and the electricity supply mains.
Appendix A of the Standard, Acceptable Means of Compliance, provides additional information as a means of ensuring your electric fence is installed and operating correctly.
If you require information on the correct installation and operation of an electric fence you can either contact your supplier of electric fence products or obtain a copy of Australian Standard AS/NZS 3014:2003 Electrical installations – Electric fences from Standards Australia on (03) 6224 2380.