Study system
Our study was conducted in the York gum woodlands of West Perenjori
Nature Reserve (29°28′01.3″S, 116°12′21.6″E) in semi-arid south-west
Western Australia (Fig. 1). York gum woodlands have a diverse understory
of winter annual plant species and a sparse overstory that creates
local-scale variation in shade and litter cover, which has been
associated with annual plant species turnover (Dwyer et al. 2015;
Wainwright et al. 2017) and population growth of some species
(Stouffer et al. 2018). In the broader region, substantial
inter-annual variation in rainfall significantly influences annual plant
community composition (Dwyer et al. 2015).