Elusive but not hypothetical: axillary meristems in Wollemia nobilis.

BACKGROUND: The branches of Wollemia nobilis are unbranched; however, it has been noted that new branches can form from the distal end of damaged ones, and branches can grow from axillary structures once a terminal strobilus has fallen. Tomlinson and Huggett (2011, Annals of Botany 107: 909-916) have recently investigated the formation of these reiterative branches and stated in the title of their paper that 'Partial shoot reiteration in Wollemia nobilis (Araucariaceae) does not arise from "axillary meristems"'. They go on to state 'Further research may reveal the presence of these elusive, but still only hypothetical, axillary meristems'. RESPONSE: In this Viewpoint, I argue that Tomlinson and Huggett do not refer to previously published information that indicates that axillary meristems are present in Wollemia nobilis branch leaf axils, and that their anatomical methods were probably not optimal for locating and examining these minute structures. Thus, whilst I would agree that the axillary meristems in branch leaf axils of Wollemia nobilis are elusive, I contend that they are not hypothetical.