Some fern species occurring in subtropical forests are restricted to shade understorey, whereas others can thrive in disturbed open habitats. Yet mechanisms underlying these distinct distribution patterns are not well understood.

Zhu et al. conducted a leaf cost–benefit analysis on ferns from either open sites of disturbed forest or understorey of natural forest. They found contrasting growth strategies for the two fern groups: ferns from disturbed forest employ a quick-return strategy that can pre-empt resources and rapidly grow in open habitats; while ferns from natural old-growth forest show a slow-return strategy allowing their persistence in the shady understorey.