This is another instance of there being two Xanthorrhoeaceae families the original strictly
defined one (s.s.) and a later losely defined (s.l.) one.
Aloeaceae, Asphodelaceae, Dianellaceae, Hemerocallidaceae, Phormiaceae and Xanthorrhoeaceae
among others were originally separate families as indicated by their ‘aceae’ ending.
In 2009 many of these were incorporated into a loosely defined Xanthorrhoeaceae s.l. which later became Asphodelaceae s.l.
Old families included in the new loosely defined one were reduced to subfamilies e.g. Xanthorrhoeaceae s.s.
The new loosely defined Asphodelaceae is used in New South Wales (around 1000 species in about 40 genera) and South
The Australian National Botanic Gardens still use the old strictly defined Xanthorrhoeaceae.
The Plant List uses a loosely defined Xanthorrhoeaceae with 24 genera including Dianella, Hemerocallis, Kniphofia,
Stypandra, Thelionema and Xanthorrhoea.
World Flora Online uses Xanthorrhoeaceae s.s. and recognises 28 species plus a number of subspecies.
I have used the loosely defined Asphodelaceae so information on Grass trees will be found in the Xanthorrhoea
genus of that family.