The Queensland DPI&F has for several years conducted a Spotted Gum (Corymbia) hybrid breeding program for the purpose of developing improved forms of Spotted Gum (Corymbia) hybrid clonal material for the plantation forestry industry, with a particular emphasis on resistance to the disease Ramularia Shoot Blight.

A series of new clonal lines of Spotted Gum (Corymbia) hybrids is now available. These clones are the first release from a seven-year breeding program and represent the best individual trees in the top 5 families grown as seedlings in three-year-old progeny trials.

The clones are hybrids between Corymbia citriodora ssp variegata (CCV) x C. torelliana (CT). They are propagated vegetatively as rooted cuttings, and show improvements in form, growth rate, drought and frost tolerance along with tolerances to Giant Wood Moth (WGM) and Ramularia Shoot Blight (RSB).

In field performance the hybrids perform as well as, or better than, CCV in terms of:

• Height & diameter of growth;
• Straightness;
• Canopy density and
• Wood properties.

and they are superior to CCV in terms of:

• Environmental plasticity (growing vigorously on a range of sites in the filed);
• Frost tolerance and
• Total field resistance to both RSB and GVM.

Spotted Gum (Corymbia) hybrid clones are now available commercially from Clonal Solutions Australia.