home | glossary | about eucalypts | about EUCLID | browse species

Hybrids


Whilst hybridism has been constantly reported in Eucalyptus no hybrids between species of different subgenera have ever been seen in the field. Moreover, manipulated hybrids between species from different subgenera have never been successful.

Hybridism requires genetic compatibility and synchronous flowering times (unless manipulated). Hybrids between species within a subgenus are rare in natural forests or scrubs. They are more likely to be seen as regrowth trees or mallees in disturbed areas where changed environmental conditions may be more amenable to the success of the hybrid combination. Hybrids in stands appear to be selected against in favour of the parent species.

Many reported hybrids are better interpreted as natural intergrades between closely related species. e.g. E. burgessiana and E. stricta in eastern New South Wales, E. dalrympleana subsp. dalrympleana and E. viminalis subsp. viminalis in Tasmania, and E. angulosa and E. incrassata in coastal South Australia and Western Australia.

There are a few well-known formally named hybrids where both parents have been identified and are seen in the field, e.g.

E. brachyphylla
(E. kruseana X E. loxophleba
subsp. lissophloia)
E. erythrandra (E. incrassata or E. angulosa X E. tetraptera),
E. missilis (E. cornuta X E. angulosa)
and possibly E. balanites (E. lanepoolei X E. decipiens).


In another example, E. annuliformis,
only one parent is evident, E. drummondii, the other being a mystery.

Many presumed hybrids have been formally named by botanists of the eucalypts over the last 200 years. The most recent annotated list of many of these names can be found in Chippendale (1988, pp. 428–442).

References