The Eucalyptus Tree in Australia

Importance

●   it provides  and food for a wide range of species

●   its leaves provide  which is used to make a disinfectant

Reasons for present decline in number

A) Diseases

(i)   `Mundulla Yellows`

●   Cause   – lime used for making  was absorbed

                   – trees were unable to take in necessary iron through their roots

(ii)   `Bell-miner Associated Die-back`

●   Cause   –   feed on eucalyptus leaves

                    – they secrete a substance containing sugar

                    – bell-miner birds are attracted by this and keep away other species

B) Bushfires

William Jackson`s theory:

●   high-frequency bushfires have impact on vegetation, resulting in the growth of 

●   mid-frequency bushfires result in the growth of eucalyptus forests, because they:

      – make more  available to the trees

      – maintain the quality of the 

●   low-frequency bushfires result in the growth of ` rainforest`, which is:

      – a  Ecosystem

      – an ideal environment for the  of the bell-miner