Puriri, the Maori name of Vitex lucens T. Kirk (Family Verbenaceae), is one of the special trees hiding off the beaten path at MEMBG. This tree has, in Sunset's Western Garden Book, also been dubbed the New Zealand chaste tree, informing you of its country of origin. The name chaste tree for this species comes from a species of southern Europe, V. agnus-castus L., where it was treated by ancients as a symbol of chastity and long ago discussed in this regard by Pliny the Elder. Puriri does not mean that the species from New Zealand is pure, but coincidentally a tree along the coast near the Bay of Plenty is treated as sacred by the Maori people; they claim that the remains of important ancestors repose in large cavities within its roots. There is one specimen estimated to be 2000 years old at New Plymouth on the North Island.
Atop the conifer slope, our 15-meter specimen is more erect than spreading, forced to grow upward by several other small trees, behind the canyon live oak (Quercus chrysolepis) and on the edge of the drop zone of a towering Pinus caribaea. Its bark is orange-brown and somewhat spongy to the touch. Very distinctive are the 4-angled young branches with long-petioled, palmately compound leaves positioned in an opposite decussate arrangement. Looking up the trunk, the main branches also seem to be arranged in four vertical rows, having arisen from the axillary buds associated with the leaves. The three, four, or, most commonly, five leaflets have short stalks (petiolules). The hairless blade of the leaflet, 13 cm (terminal) to 3 cm (lowest) in length, is elliptic to oblong in shape, strongly pinnately veined and weakly folded along the midvein, somewhat leathery, and rather shiny on the upper side. Below the leaflet you can, with good magnification, observe a swelling with a hollow center in each angle where a lateral vein departs the midvein; these are domatia, used as minute homes for tiny arthropods, probably mites.
Probably most gardeners are familiar with the Verbenaceae by knowing the widely cultivated species of either Lantana or Verbena, which also have the four-angled stems. Other woody vervains are species of Clerodendrum and Duranta repens, which are also cultivated at MEMBG, as is the Chinese hat plant, Holmskioldia sanguinea. Flowers in this plant family tend to be colorful, and for puriri that is certainly the case. From an axillary bud arises a marvelously branched inflorescence, called a cyme, often with about a dozen buds, but only one or a few flowers are ever open at the same time. Each stalked flower is dark pink to rose, darkening as it ages, about 3.5 cm long and 2.5 cm either direction across its face. The calyx is cuplike and green, but the showy corolla has either four or five distinct lobes surrounding a slightly curved floral tube. Toward the top side of the flower project four stamens with white filaments and small, brownish anthers filled with sticky pollen grains, which resemble insect eggs. The pistil curves downward slightly and bears a forked tip for a stigma. Nectar is copious. Flowering begins in May. On the ground beneath the tree can be found hundreds of the rose-colored corollas, which abscised after flowering. The fruit is a globose drupe (20 mm), a fleshy fruit with a juicy red cover and a hard endocarp. In New Zealand the fruits are cherished by birds.
One reason the trees of this species live so long is because it has a very strong and durable wood with reddish-brown heartwood. Consequently, I never expect, in my tenure as director, to see this plant rot and blow over-not that we experience violent tropical storms here in Westwood.
ARTHUR C. GIBSON, MEMBG Director