PLANT MORPHOGENESIS FOR SCIENTIFIC MANAGEMENT OF RANGE RESOURCES 



67 



Acacia Communities 



Figure 5 (Wilcox unpublished) shows the fluc- 

 tuations in productivity which occurred in a 

 mulga (Acacia aneura) community due to varia- 

 tions in annual rainfall effectiveness. As in the 

 halophytic pastures, animals clearly must depend 

 upon dietary sources other than herbage if they 

 are to survive during periods of moisture stress. 



Mulga- communities have been exploited to 

 provide a diet for sheep and cattle. Nichols (22) 

 reported the successful feeding of large flocks of 

 sheep on fallen mulga in Western Australia. 

 Melville (19) described a number of Acacia spe- 

 cies in Western Australia which can be fed to 

 sheep once they are felled. He also drew atten- 

 tion to differences in the acceptability of mulga, 

 a difference he ascribed to the level of ether ex- 



tractable constituents in the phyllodes which may 

 rise to 12 percent in unpalatable varieties. 



In Queensland, Everist (8) suggested forms of 

 mulga tree cutting which allow for the regrowth 

 of the cut tree after rain. He also suggested the 

 number of trees which should be left in the com- 

 munity to provide for regeneration. It should be 

 noted in this discussion of A. aneura, and associ- 

 ated tree forms that their value, particularly for 

 sheep, only becomes apparent after they have 

 been felled and the edible material becomes avail- 

 able. There has been no recorded work on the 

 rate of rrmlga regrowth after lopping, nor any 

 indication of the amount of lopping which could 

 be permitted without erosion of the reserve of 

 standing forage. 



Rehabilitation of cut stands of mulga depends 

 upon the successful colonization of the com- 



St 1 '95-e> ' i960 ' 1961 ' '962 ' '96* ' '964 ' '9** 



Figuke 5. — Variation in ground species production in a mulga-short grass-forb community in Western Australia. 



