47 
No. 124. 
Eucalyptus Sieberiana, F.v.M. 
Yowut or Mountain Ash. 
(Family MYRTACE^E.) 
Botanical description. —Genus, Eucalyptus. (See Part II, p. 33.) 
Botanical description. —Species, E. Sieberiana, F.v.M. in “ Eucalyptographia ” 
(1879). 
It may be described in the following words :— 
Juvenile leaves. —The seedling leaves are vertically arranged ; of the same colour on both sides ; 
glaucous, and larger than those of E. piperita. The venation is rather acute with the 
midrib. Both seedling and sucker leaves are glaucous, dull-coloured on drying, and have 
the veins more spreading than is the case in the mature foliage. 
Mature leaves. —The leaves, which are falcate, lanceolate, and about 5 inches long by 1 inch wide, 
are often smooth, shining and coriaceous. The venation is spreading. 
Buds clavate. 
Operculum. —Hemispherical or slightly umbonate. Pale-coloured opercula are often observed in 
the Blue Mountains. Double opercula sometimes occur in this species. 
Inflorescence. —Frequently ocellate; this is sometimes a useful guide in distinguishing this from 
allied species. 
Fruits. —Pear-shaped, usually a little oblique, the rim sometimes slightly concave, particularly 
when ripe. Edge of rim frequently sharp. Sometimes the plane of the rim is not at right 
angles to the axis of the fruit. Shining. The rim usually well defined, and often dark as 
in E. hcemastoma. 
Botanical Name. — Eucalyptus, already explained (see Part II, p. 34); 
Sieberiana , in honour of Franz Wilhelm Sieber, of Prague, Bohemia, a botanical 
collector, who spent seven months in New South Wales in 1823, making collections, 
which were sold in numbered sets, bearing the labels “ Flor. Nov. Holl.” and “PI. 
Exs.” (exoticse). He collected Eucalypts amongst other plants. 
Vernacular Names. —“ Mountain Ash ” is its usual name. It attains its 
greatest luxuriance in mountain districts, and its timber is thought to resemble ash. 
Sometimes called “ Black Ash,” but this name should be reserved for E. stellulata. 
In Tasmania and in Victoria it is sometimes called “ Gam-top ” or “ Gum-top 
Stringybark ” (in allusion to the smoothness of the tops of the brauches), and 
“ White-top Ironbark ” in Tasmania, where there are no true Ironbarks. It has been 
also called “ Blackbutt,” but that name should be reserved for E. pilularis. It has 
been called “Messmate” or “Stringybark” at the Dromedary, N.S.W., but the use 
of such names for this species is to be deprecated. 
