Strategic management of Aleppo Pines on Lower Eyre

2 THE ALEPPO PINE ON EYRE PENINSULA
2.1 Ecology
The <strong>Aleppo</strong> Pine (Pinus halepensis Mill.) is a large (25-30 metre) coniferous species from the
Mediterranean (Figure 1). Its natural distribution extends from Morocco in the west to Jordan in the
east, and from France in the north to Palestine in the south. <strong>Aleppo</strong> <strong>Pines</strong> have serotinus cones,
that is, seeds are produced, stored and protected in the canopy. Cones take three seasons to
mature and the viability <strong>of</strong> canopy-stored seed can be maintained for as long as 20-50 years
(Daskalakou and Thanos 1996).
Figure 1 <strong>Aleppo</strong> Pine (Pinus halepensis) (Photo: Jason van Weenan)
<strong>Aleppo</strong> Pine cones open and release seed in response to disturbance (e.g. fire and being felled)
and their permanent, long-term seed bank is a key feature for post fire regeneration. <strong>Aleppo</strong> <strong>Pines</strong>
are prolific seeders. Research in Greece estimated <strong>Aleppo</strong> <strong>Pines</strong> could produce an annual seed
rain (dispersed in fire-free conditions) <strong>of</strong> between 25-105 seeds per square metre (Daskalakou and
Thanos 1996) or 17,400 seeds per year for mature trees (Virtue and Melland 1999). This makes
control particularly difficult and follow up <strong>management</strong> is crucial to control mass germination and
seedling growth.
<strong>Aleppo</strong> Pine seeds are wind dispersed and can carry for considerable distances on prevailing
winds, however the majority <strong>of</strong> seeds fall to within 40-50 metres <strong>of</strong> the parent tree (Bulman 1992).
Soil seed-banks are significantly short-lived compared to canopy storage. Germinable seed
content in the soil has been shown to rapidly deplete following the first rainy season (Daskalakou
and Thanos 1996).
The species is particularly robust and can quickly re-shoot from the smallest piece <strong>of</strong> foliage missed
during control operations. Herbicides such as ‘Brush<strong>of</strong>f’ and ‘Trounce’ (Ally plus Glyphosate) have
also proven ineffective.
2.2 History and distribution on Eyre Peninsula
<strong>Aleppo</strong> <strong>Pines</strong> were introduced to Eyre Peninsula by the forestry industry in the early 1800s. <strong>Aleppo</strong>
<strong>Pines</strong> grew quickly and responded well to Eyre Peninsula’s calcareous soils and Mediterranean
climate (annual rainfall <strong>of</strong> 300-600 mm). Being quite a large and fast-growing species, <strong>Aleppo</strong>
<strong>Pines</strong> proved ideal for windbreaks around farmhouses and buildings, as well as stock shelterbelts.
Consequently, <strong>Aleppo</strong> <strong>Pines</strong> were widely planted on lower EP by early settlers and later throughout
the soldier settlements after World War II. <strong>Aleppo</strong> <strong>Pines</strong> were still recommended for this purpose by
the Department for Agriculture up until the mid 1980s.
In South Australia, naturalised populations <strong>of</strong> <strong>Aleppo</strong> <strong>Pines</strong> exist throughout lower Eyre Peninsula,
parts <strong>of</strong> Yorke Peninsula and the southern Mount L<strong>of</strong>ty region. On lower Eyre Peninsula, severe
infestations <strong>of</strong> <strong>Aleppo</strong> <strong>Pines</strong> occur along Flinders Highway and many roadside reserves, Uley
Wanilla, Uley South and Lincoln Basins (SA Water Corporation) and Kellidie Bay Conservation Park
(Department for Environment and Heritage).
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<strong>Strategic</strong> <strong>management</strong> <strong>of</strong> <strong>Aleppo</strong> <strong>Pines</strong> on Lower Eyre Peninsula to maximise biodiversity conservation outcomes