6.0 ENRICHMENT AND REPLACEMENT PLANTING

The survival and permanent conservation of the Lugarno urban forest and woodlands is totally reliant on enrichment and replacement planting.

No natural regeneration of the trees in non bushland areas can occur as the understorey is regularly mown.

As many of the existing trees are mature and appear to be relatively even aged it can be expected that major tree mortality will occur over the next ten to thirty years.

Replacement planting involves the propagation from LOCAL GENETIC STOCK of trees for replenishing the existing stands and preventing long-term depletion.

Enrichment planting is the propagation from LOCAL GENETIC STOCK of trees whose Populations are low in number and the planting of these propagated plants within or adjoining existing stands to increase their size and long-term viability. In some cases this may also require the careful choice of a variety of genetic sources WITHIN THE STUDY AREA to ensure that in-breeding is prevented.

For example, in the case of the Brown Stringybark with its four small Populations, seed should be collected from each population and the propagated plants replanted with a mixture at each population.

However, where distinct genotypes occur, such as the two types of Scribbly Gum, plantings should be kept separate. That is plants propagated from Eucalyptus haemastoma seed should not be planted on the clay areas amongst the Eucalyptus "haemarac".

Throughout this report, the concept of propagating only from LOCAL GENETIC STOCK has been emphasised. This ensures that the historic and unique genetic qualities of the local plant populations are preserved. In many cases such unique features will only be recognised or identified in future years as horticulturalists, botanists and ecology students study the Lugarno trees. For example, the uniqueness of Eucalyptus "haemarac" has only be known for the past three years.

The planting of local species from non-local genetic stock will degrade and even destroy the heritage values of the Lugarno forest and woodlands.

It is strongly urged that Hurstville City Council adopt a Policy of only utilising LOCAL GENETIC STOCK when planting local native plant species in the Study Area.

It is also recommended that Council adopt a policy, wherever practical, of utilising local native plant species propagated from LOCAL GENETIC STOCK when planting in parks or streets in the Study Area and that appropriate species be chosen for each site as outlined in the next section of this report - "7.0 Landscape Values".

The Trust understands that propagation of the seventeen Lugarno Study Area species is already underway by local community groups using seed collected in the Area and that large numbers of these plants will be available later in 1990.