Eucalyptus boliviana is known as the Bolivia Hill Stringybark and develops into either a single-trunked tree reaching a height of about 12 metres or a 5-metre, multi-stemmed mallee, spreading to several metres wide.
It is endemic to NSW and is very rare, occurring only on the northern tablelands, in a single area north of Deepwater (south of Tenterfield), at a location called Bolivia Hill.
It grows on granite outcrops, in dry sclerophyll forest and mallee woodlands.
It is a listed threatened species in NSW.
Branchlets are square and dull green with a whitish bloom. This is an unusual feature in mature eucalypts.
Eucalyptus spp. have simple and usually alternate adult leaves with juvenile leaves starting off opposite to alternate (disjunct). In this species, the juvenile leaves are broadly lanceolate, to 16 cm long and 5 cm wide, starting blue-green but aging to green. Adult leaves are initially leathery, dull green then age to glossy green. Mature leaves range in size from 8 to 16 cm in length, by 5 cm wide.
The primary inflorescence of “eucalypts” (Angophora / Corymbia / Eucalyptus) is an umbellaster (an umbel-like cluster of flowers). In the flowers of Corymbia and Eucalyptus, the petals and sepals are fused into the distinctive calyptra / operculum (bud cap) which is shed when the flower opens (in some species, 2 bud caps (opercula) are shed). The flowers are conspicuously staminate – where many stamens are basically taking over the role of the petals, all surrounding one central carpel. In this species, the buds are held in umbellasters of 7, or sometimes 2s and 3s, ovoid, to 1 cm long and angular in cross-section – sometimes squarish or wedge-shaped. Flowers are cream to yellow, produced in July to September.
The fruit of eucalypts are a woody capsule (commonly called ‘gum nuts’) which come in a wide variety of shapes with the top part having a sunken, flat or raised disc and with the valves inserted, disc-level, exserted to strongly exserted. In this species, fruit are hemispherical to funnel-shaped, to 6 mm long and 15 mm wide and tightly clustered together in each umbellaster.
An excellent specimen tree. Not widely cultivated as it is a threatened species. Check with local native nurseries for information and availability. An attractive mallee to grow.
Cultivated plants will usually have a single trunk as does the specimen in our cold climate garden. The flowers, on our specimen, are cream although the botanical description gives their colour as yellow.
Eucalyptus boliviana is one of Australia’s rarest Eucalypts. The total population is calculated at less than 1500 individuals.
Fortunately the species is coming into cultivation, thanks mainly to the Armidale Tree Group, the local community nursery, so the future of this rare and unusual Eucalypt is assured.
We have found Eucalyptus boliviana to be hardy and resistant to both drought and frost.
Propagate from seed.
This species can likely regenerate from lignotuber and epicormic shoots after fire. Likely detrimented by too much fire.
It is well-known that Eucalyptus is a large and diverse genus. Between 700 and 950 known species are reported, occurring as far north as The Philippines, as well as Indonesia, New Guinea, Timor and Australia. Only 16 species reportedly occur outside Australia. They occur in all Australian states. NSW currently has about 250 species. (See this website for some detailed information: https://apps.lucidcentral.org/euclid/text/intro/learn.htm).
Eucalyptus – from Greek, eu, “well” or “true” and calyptus, referring to the calyptra (καλύπτρo) or operculum, which is a bud cap or covering which covers the developing flowers. The calyptra is a fusion of petals and/or sepals and is shed when the flower opens, leaving a flower with many stamens (staminate) surrounding one female part (carpel).
boliviana – named for the Bolivia Hill ranges between Glen Innes and Tenterfield in NSW.
This species is listed as being threatened with extinction in the wild at the State level with the category of vulnerable.
NSW Flora Online (PlantNET) – Eucalyptus boliviana profile page https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Eucalyptus~boliviana
NSW Office of Environment and Heritage – Threatened Species Profile – Eucalyptus boliviana https://www.environment.nsw.gov.au/threatenedspeciesapp/profile.aspx?id=10285
EUCLID – Eucalypts of Australia – Centre for Australian National Biodiversity Research – Eucalyptus boliviana profile page https://apps.lucidcentral.org/euclid/text/entities/eucalyptus_boliviana.htm