xliv. 
Charles Austin Gardner. 
Agonis and Banksia, Melaleuca and Hakea, with a herbaceous ground 
covering in which the shrubs are comparatively few. To the north the 
undergrowdh becomes shrubby, but retains something of the naturt' of 
savannah, and when the shrubby undergrowth is destroyed there is a ten- 
dency towards the development of grass at the expense of the shrubby growth, 
thereby indicating a succession in the direction of pure savannah forest. 
In contrast to the jarrah, karri, and marri, the tuart tree is of the " box ” 
type, the real environment of which is the savannah formation. (“ Box ” 
is a vernacular term applied to Eucalyptus trees with entirely rough grey 
bark.) 
(b) The Woodland Formations. 
(i) Savannah (temperate) Woodland, 
In the granitic soils of the jarrah forest of the Darling Range the wandoo 
tree (Eucalyptus redunca var elata) occurs where the subsoil is of a clayey 
nature. Here it never dominates the forest, but is found in small numbers 
in the gi’anitic areas. To the east of the 385 mm. seasonal isohyet however, 
it becomes the dominant tree, usually associated with Eucalyptus foecunda 
var. loxophleha and Acacia acuminata, forming open savannah-like country 
with a low shrubby or herbaceous undergrowth. It is usually associated 
with shallow granitic soils, but extends into deeper clay soils, especially in 
the south, or into sandy country to the east and north, ultimately (about 
the 200 mm. seasonal isohyet) becoming associated with decomposed laterite. 
Towards the northern part of its range the species is increasingly associated 
with E. foecunda var. loxophleha, and Acacia acuminata, giving place to these 
two latter species entirely in the latitude of Arrino, to the nortli of which 
the savannah woodland formation is composed almost entirely of these two 
species as far north as Northampton. To the south, in the vicinity of Wagin, 
the character of the savannah woodland undergoes a change, and Eucalyptus 
occidentalis becomes important, especially in the low-lying clay soil, while 
the wandoo becomes restricted to the sand, until finally, in the vicinity of 
Cranbrook, the wandoo disappears entirely, and its place as a savannah tree 
is taken by both Eucalyptus occidentalis and E, cornuta, the former in the 
clay soils, and the latter confined to granitic areas. Between Cranbrook 
and Gnowangeru[) the zone limited by the 385 and 200 mm. isohyets curves 
sharply eastwards, to extend along the south coast, and here the two trees 
continue as far east as the Russell Range, forming in places areas of o]jen 
grassy granitic country in which either or both trees occur. This is country 
more suitable for grassland development than the area to the north, on 
account of the higher summer precipitations. The formation ceases to exist 
to the east of Israelite Bay. Throughout the whole extent of its area of 
distribution it is intersected by zones of sand-heath. 
(ii) The Sclerophyllous Woodland, 
Somewhere in the vicinity of the 225 mm. isohyet the loamy soils support 
a type of woodland which is in contrast to the savannah woodland because 
of the density of its arborescent species, the greater development of shrubs, 
and the paucity of grasses except those of a harsh tussocky nature. The 
formation usually occurs on low-lying soils, and the woodland either consists 
entirely of trees about 25 metres with an undergrowth of shrubs about a 
metre higli, and bare soil beneath, or there may be a development of slimbby 
Eucalyptus species known as mallees. The formation extends as far east 
as Zanthus, and northwards to the mulga bush formation, but its eastward 
extension is sharply limited by the limestone soil of the Nuliarbor Plain, 
