Tremont - Mount Dandenong Tourist Road
About tree ferns
The Dandenong Ranges is home to many magnificent trees and plants. The beauty and elegance of tree ferns are among the first images recorded by visitors. Adjoining banks of creeks, meandering through fern gullies, dotted between the eucalypts and providing delicate borders to the roads and tracks, these beautiful trees have their ancestry in the Jurassic period.
Unlike the bark and wood trunks of seed trees, the trunk of a tree fern has a central region composed of rhizomes that grow vertically and is surrounded by a thick mantle of frond bases and fibrous roots. Some of these trunks are slow growing, typically 1-10 cms a year and can reach heights of 20+ metres.
At the top of the trunk, the growing tip, tightly curled young fronds slowly unfurl as they reach the adult stage. These delicate fronds grow out in an umbrella shape, some reaching several metres in length.
The battle for survival
Tree ferns are constantly under threat from many sources:
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Water stress from drought and low levels of humidity
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Bushfires
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Susceptible to bacterial and fungal rot
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Natural home for sap-sucking insects
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Demand for landscaping and gardening material
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Used as craft material
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Land clearance
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Council, electrical, roadside and water management services
A perfect host
Unlike the trunks of soft or hardwood trees, the thick fibrous trunks of tree ferns provide the perfect growing medium for seeds deposited by birds or blown in the wind.
The intersection of the frond and the trunk also offers a “cup” to trap seeds
Seeds, from near by plants including weeds, have germinated in the moist conditions offered by the trunks of old tree ferns.
The thick ivy stem is strangling this tree fern while new ivy plants are growing from the trunk itself.
Ivy conquers
The biggest threat of all comes from ivy. Unlike most trees that get their water and nutrients from below the ground, tree ferns and other ferns need their water directed to the top of the plant, the growing tip.
The slow growing tree ferns (only 10cms in 10 years for some species) are quickly engulfed by the insatiable ivy which rapidly climbs the fibrous outer trunk, setting its own roots into the surface as it encircles and entwines reaching for the crown, its ultimate goal.
The tree fern on the right had ivy removed two years ago by cutting and removing a band of ivy around the base of the tree fern - the recommended method for removing ivy from a tree.
The ivy, rooted into the trunk, continued to grow above the band and new growth has appeared at the base.
To remove ivy from densely invaded tree ferns, like these, will take considerable time and effort.
Ivy wins
Ivy quickly overtakes the fern.
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Starves the plant of essential rain water
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Prevents moisture/water from reaching the trunk
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Prevents native birds and animals from nesting in
the crown. -
Smothers the young fronds
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Stunts the fronds
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Causes deformity
Ivy can never be removed successfully from the fibrous trunks of tree ferns.
Ivy kills ferns and tree ferns!
