Mapou forms a shrub to small tree about 6m tall. It's red brachlets, reflected in the common name red matipo, and wavy leaves dotted with oil glands, are distinguishing features. Mapou is found throughout New Zealand in forest margins and scrubland and is a vital part of regenerating native bush.
The trees are dioecious (separate male and female). Small cream coloured flowers appear, crowded along branchlets, from mid-summer to mid-autumn. Female trees produce small fruits which are a drupe with a single seed. They ripen to a black colour about a year following flowering. The flesh of the fruit contains two important yellow pigmented carotenoids: lutein and zeanthin. These substances provide animals with bright colouration as well as being anti-oxidants. Hihi relish ripe mapou fruit. It gives good feather colour for male birds and rich, healthy eggs for females.