May 9, 1950. 
THE SOUTH AUSTRALIAN NATURALIST 
Page Nineteen 
ginal vein almost invariably coincides with 
the margin, giving it a thick, rolled appear- 
ance. 
Both species bear very large, bright golden 
flower heads. 
They may be definitely distinguished if 
pods are available, since the seeds of Acacia 
notabilis are transverse, while those of Acacia 
pycnantha are longitudinal. 
In conclusion, a little may be said of the 
principal Acacias used in our hills and sub- 
urban gardens. Of those commonly used, 
only one is a phyllodinous type. This is 
Acacia podalyriae folia, Queensland or Mount 
Morgan Wattle, which has short, obovate 
phyllodes, and the whole tree is so glaucous 
as to appear silvery-grey. It bears flowers 
prolifically in axillary racemes in August and 
early September. 
The remaining cultivated Acacias of im- 
portance are all feather leafs, and fall natu- 
rally into two groups: 
(1) Foliage silvery grey, or greyish: 
Cootamundra Wattle (Acacia Bailey- 
ana) 
Silver Wattle (Acacia dealbata) 
and 
(2) Foliage green: 
Black Wattle (Acacia mollissima) 
Green Wattle (Acacia decurrens). 
The “leaves” of all these species are really 
pinnules. These are grouped in pairs along 
a common stalk, together with which they 
form pinnae. These in turn are grouped in 
pairs along a larger common stalk, and the 
whole thing forms the leaf proper. 
In distinguishing between the Cootamundra 
and Silver Wattles, the length of the pinnules 
is important. The pinnules at the outer ends 
of the pinnae of the Cootamundra are shorter 
than those further down the “stalk,” which 
become progressively longer for about two- 
thirds of the length of the pinna, and then 
begin to shorten again, thus giving the pinna 
— in OUTLINE — a rather oval shape. The 
outline of a Silver Wattle pinna is oblong, 
the pinnules all being of practically the same 
length. Also the pinnules of the Silver 
Wattle are finer than those of the Cootamun- 
dra. The Cootamundra is by far the most 
widely planted, and is often, though wrongly, 
called Silver Wattle. 
The distinction between the Black and 
Green Wattles is difficult. Some botanists 
regard them as varieties of the same species. 
Generally, however, the number of pairs of 
pinnae per leaf is greater (10 to 18) in the 
Black Wattle than in the Green (less than 
10). In Victoria and the south-east of South 
Australia, where it occurs naturally, the 
Green Wattle flowers from mid winter to 
mid spring, while the Black Wattle blooms 
in the summer time, from September to 
March, and it is possible that the same 
distinction could be used in the wetter parts 
of this State, including the Adelaide Hills 
and Plains. 
KEY TO THE ACACIAS (WATTLES) OF THE ADELAIDE HILLS. 
A. PHYLLODINOUS WATTLES (Phyllodineae) 
B. Flowers in spikes 
C. Phyllodia whorled, subulate (awl-shaped) 
A cacia verticillata . 
C. Phyllodia thick, with 2-5 prominent nerves. 
Acacia longi folia. 
B. Flowers in globular heads 
C. Plants with no phyllodes, or with phyllodes reduced to spines (Aphyllae) 
D. Spines articulate on the stem, flower heads borne on the spines 
Acacia spinescens. 
D. Spines continuous, flower heads borne in the axils between phyllodes and 
stem. Acacia continua. 
C. Plants with phyllodes with three or more longitudinal nerves, flowers very 
pale. Acacia melanoxylon. 
C. Plants with phyllodes with two nerves. 
A cacia verniciflua . 
C. Plants with phyllodes with one nerve. 
I). Phyllodes rigid and pungent-pointed. 
E. Phyllodes linear-lanceolate, seeds with a broad aril. 
Acacia rupicola. 
