POM- Who-is-a-sap

Plant of the Month: Who’s a Sap?

Flora, Newsletters, Plant of the Month, The Scoop

The next group of Eucalypt like trees we’re looking at are the bloodwoods. The bloodwoods derive their common name from the large amount of sap they produce, previously listed in the Eucalyptus they were split off into the Corymbia genus in the 1990’s. Apart from the often copious amounts of sap they produce they are distinguished by their urn shaped nuts and the flowers arranged in a corymb*.

The better known of the Corymbias are the Lemon Scented Gum (Corymbia citriodora), Red Flowering Gum (Corymbia ficifolia), Spotted Gum (Corymbia maculata) and the environmental weed Cadaghi (Corymbia torelliana).

Spotted Gum (Corymbia maculata) is often used for construction timber and floorboards and is regarded as one of the best timbers for tool handles.

(*A corymb is an arrangement of flowers where despite originating at different levels on the stem occur at more or less the same level on the inflorescence).

 

Two examples of Corymb flower arrangement (source Wikipedia).

Corymbia maculata fruit 7

Corymbia maculata (Spotted Gum) showing coymb arrangement and urn shaped (urceolate) fruit.

Key to the Hunter Region’s Corymbia

1         Bark smooth with purplish blotches

Corymbia maculata             Spotted Gum

Common on moderate fertility soils throughout the region, becoming scarcer further inland occurring to west of Merriwa

Corymbia maculata trunk

Corymbia maculata trunk

1* Bark persistent and tasselated

2 Fruit 5-8mm diameter

Corymbia trachyphloia  subsp. amphistomatica White Bloodwood/Brown Bloodwood

Generally found on sandstone escarpments north from the Goulburn River National Park

Corymbia trachyphloia bark

Corymbia trachyphloia trunk

2* Fruit 8-19mm diameter

3 Adult leaves concolorous (same colour both sides)

            Corymbia eximia                Yellow Bloodwood

On infertile soils on sandstone south from Howes Valley

3* Adult leaves discolorous (different colours on both sides)

4 Bark flaking off on smaller branches

Corymbia gummifera     Red Bloodwood

Generally coastal inland to around Cessnock on low fertility sand or sandstone soils

4* Bark persistent on smaller branches

                      Corymbia intermedia     Pink Bloodwood

On moderate fertility soil, north from around Bulahdelah