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Tallong Midge Orchid

The Survivors
by Greg Stone

Fire in the Bush
by Greg Stone

More Road Kill
by Phil Mosies

Injured Native Wildlife
Emergency Management

Goldrush Grog
by Phil Mosies

Spring Purples and Pinks
by Greg Stone

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The Spotted Gums
by Greg Stone

Winter Fires
in Tallong

In The Natural Interest

Fire in the Bush
by Greg Stone
Shoalhaven GorgeAmongst the numerous news reports broadcast during the fire crisis of late December and early January were statements to the effect that bushland - more specifically a national park - had ' been totally destroyed by fire'.

Representatives of the National Parks and Wildlife Service were quick to remind journalists that fire is a part of the natural life-cycle of much of our local bushland and is in fact necessary for the long-term health and vitality of communities of native vegetation. Fire can bring about a dramatic increase in the population of new plants which replace the older members of the community, thus extending its life.

Most of the remaining bushland communities in the Tallong -Wingello - Penrose - Canyonleigh area occur on dry, well-drained and infertile soils based on Hawkesbury Sandstone, and most of the plant species growing in these fire-prone (hard-leaved) communities have been especially designed with 'bushfire survival' mechanisms.

In the December edition of the Southern Highland Way we considered how plants survive and recover after a bushfire. In response to a fire, plants can be placed in either of the two basic groups - 'sprouters ' and 'seeders'. The 'sprouters ' are those plants that send out new vegetative growth after the fire, whereas the 'seeders' obviously survive by preserving seeds in a variety of ways which allow germination to occur following fire damage. So in relation to fire in the bush the word 'destroyed' is probably not quite correct. 'Modified' or 'rejuvenated' may be more appropriate.

However, this is not to say that fire is always beneficial to the bush, because under certain conditions it is possible that fire may damage or even destroy a community of natural vegetation. Factors to be considered by those responsible for fire management in the bush are the frequency of fires, the intensity of the fire and the timing of the fire


Frequency of Fire
A plant must first reach reproductive maturity if it is to regenerate itself following a fire i.e. it must be old enough to have produced seed or 'sprouting' mechanisms such as epicormic buds or rhizomes. This age of reproductive maturity differs between species found in typical vegetation in this region may vary from two years (Acacia sp.) up to fifteen years (Banksia serrata). This means that all the species in a patch of bush burnt this year will begin to regenerate almost immediately - but what will happen if a similar fire occurs in three years time?

Those species which have matured quickly will again be able to respond and regenerate, but those still reproductively immature will not. So although the bush will grow back, there will be a number of species missing. As ecologists put it, the vegetation community will move from complexity (many species of plants) to simplicity (fewer species of plants). Therefore both the frequency of fires - whether wildfire or for hazard reduction - and the lifecycle of plants need to be considered by the managers of bushland areas.


Intensity of the Fire
Low intensity fires are often regularly applied to the bush during Autumn or Spring for the purpose of hazzard reduction i.e. reducing the amount of fuel present so as to keep potential bushfire intensities low and manageable.

These frequent low-intensity fires may significantly modify the plant community in several ways. The fires may destroy shrubs yet not be hot enough to stimulate seedlings to germinate, but will still allow regeneration from rhizomes and other underground rootstocks. After several such low-intensity burns the bush may consequently become dominated by grasses and ferns. Shrub and tree which regenerate from epicormic buds, lignotubers and rootstocks may become exhausted after frequent fires and therefore also be lost to the community. Again, the bush moves from complexity to simplicity.


Timing of the Fire
Spring is critically reproductive time for many plant species - bearing flowers or producing immature fruit. Regular hazard reduction burning during this season can obviously have a adverse effect upon a bushland community as some species will be prevented from reproducing.


January 2002, South MarulanFire Planning and Management
Nobody can accurately foresee the occurrence of fires and conditions such as those recently experienced, but in the meantime we do have the opportunity to carefully develop plans and then implement fire management strategies in areas of natural vegetation that will serve to both minimize the risk to life and property whilst also preserving our bushland.


Greg Stone
Woodlands Revegetation

C/- P. O. Wingello
Wingello N.S.W. 2579


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