Wednesday 1 June 2016

Eucalyptus camaldulensis - River Red Gum

Eucalyptus camaldulensis is the river red gum, a tree of the Myrtaceae family.  It is native to Australia, where it naturally distributed along many inland water courses as well as floodplains.  Due to the proximity to watercourse, river red gum is subject to regulate flooding in its natural habitat.

The generic name ‘Eucalyptus’ is from the Greek words ‘eu’ good or well, and ‘kalyptos’ covered, referring to the calyx which forms a lid over the flowers when in bud.  Specific name “camaldulensis” referring to L’Hortus Camaldulensis di Napoli, from where the first specimen was first described by Frederick dehnhardt, in 1832.  The Camaldoli garden, which was established in 1816 by Francesco Ricciardi, Count Camaldoli, features collections of Acacia, Agavaceae, Melaleuca, Eucalyptus camaldulensis, and Quercus ilex.


River red gum is tolerant to waterlogging, as well as drought, salinity, fire and frost.  Globally, E. camaldulensis is widely planted in arid and semi-arid lands.

E. camaldulensis can grow up to 45 meters tall.  The tree has a large, dense crown.  The base of the bole can be covered with rough, reddish-brown bark.   The dull blue-green coloured leaves contain oil-producing glands in the un-veined areas. 



USES

Due to its fast-growing nature, it is cultivated for the wood.  Eucalyptus plantations are popular with honey producers, as they are safe and sheltered, and very few agro-chemicals are used.

River red gum wood is hard and dense (≈900kg/m3), but brittle, thus making hand working difficult.  It is used in rot resistant applications such as fence posts, sleepers, decks and wooden floors.  It is also popular firewood, the wood makes fine charcoal. 

E. camaldulensis is a natural biological drainage (biodrainage), often used to reclaim swampy sites.  The tree’s root can penetrate deep into the soil, capable to draw a tremendous amount of water from the ground, thus removing the water from the swamp.



HAZARDS

River red gum and many other Eucalypts was nicknamed, “widow maker”, as they tends to drop large branch without warning.  This form of self-pruning may be a means of saving water or simply a result of its brittle wood.

E. camaldulensis is known to exhibit allelopathic characteristic.  Several volatile and water-soluble toxins found in Eucalyptus tissues inhibit other plant species from growing nearby.  Accumulated Eucalyptus litters inhibit seeds germination, and stunted seedling growth.

Eucalypts draw a tremendous amount of water from the soil through the process of transpiration.  This may contribute to depletion of ground water and soil moisture.


Large amount of Eucalpytus litters, combine with the volatile oil produced by the leaves, lead to fire hazard in Eucalpytus plantation.