Johnson and Briggs (1975) applied the "aluminon" test to 72 species in 48 genera of the Proteaceae and concluded that almost all genera of both intermediate and sclerophyllous habitats are nonhyperaccumulators.
We would like to emphasize that information on aluminum hyperaccumulation can be gathered easily in unexplored families by simple but adequate methods, such as the aluminon test of leaves (Chenery, 1948a) or the chrome azurol-S test of wood (Kukachka & Miller, 1980).
In each case the concentration of Al, measured by use of PCV and aluminon, is compared with the sum of the concentrations of free [Al.sup.3+] and mononuclear [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] species, as determined from stability constant data.
Aluminium was determined using the PCV and aluminon methods.
The aluminon method was also essentially that used by Kerven et al.
The concentration of Al in each solution was measured with the aluminon method.
For both the PCV and aluminon methods the experiments were repeated at the 30 s reaction time.
The values of Al measured with the PCV and aluminon methods were compared with values of [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] predicted from stability constant data.
Results for the determination of Al with the aluminon method as a function of reaction time are given in Fig.
Concentrations of Al from the 500 [micro]m Al solutions in the presence of various concentrations of organic acids, as measured with the aluminon method at several reaction times, are shown in Fig.
A similar pattern of results was obtained when the concentration of Al from the 100 [micro]M Al-organic acid solutions was determined with the aluminon method (Fig.