Beach Naupaka: Scaevola taccada
There are two varieties of beach naupaka. The common S. taccada
var. sericea has silky plant hairs on the stem and leaves, and the
less common S. taccada var. taccada, appears to be smooth, lacking
Look for first:
- rounded shrub
- white "half-flower"
- white clusters of fruit
- large, mostly erect leaves, with wavy margins and small
indentations at the apex
||Leaves: Blades 4 to 21 cm long, 1.8 to 9 cm
wide, appearing elliptic to spoon-shaped; leaf edges sometimes
curved downward, somewhat succulent, but not stiff or thickskinned;
broad apex often having shallow indentations.
||Flowers: Dense axillary clusters emerge in
groups of three, all flowers stalked. Five white petals (about 2 cm
long) extend halfway around the flower, like a semi-circle,
resulting in the name "half-flower;" sometimes appear pinkish
||Fruits: Round to elliptical drupes measure
about 1 to 1.7 cm, white to yellowish-white. Plants can produce
fruits within their first or second year.
Beach naupaka is also known as Hawaiian half-flower.
Its distinctive flower makes it easy to identify; however, it can
be confused with the native inkberry (Scaevola plumieri), whose
flowers look similar. Inkberry has black fruits, and its leaves are
stiffer, smaller (to 10 cm long), with a smooth, entire leaf
margin. By contrast, the beach naupaka has white fruits and leaves
that grow to about 21 cm in length and often have a few shallow
indentations along its
Beach naupaka is a large bushy shrub
native to southeastern Asia, eastern Africa, Australia and the
Pacific Islands, including Hawaii. The salt-tolerant beach
naupaka has been available from nurseries since the 1960s. It was
promoted in the 1970s and 1980s for use in beach stabilization
projects and coastal landscapes - a practice that continues, but is
now discouraged. Beach naupaka escaped cultivation by the
early 1980s and now forms dense stands on many beach dunes, coastal
rock barrens, coastal strands, along saline shores, including
mangroves, and in coastal hammocks.
Beach naupaka has been offered and planted as inkberry by the
nursery trade, resulting in accidental and intentional
introductions in natural areas.
Frost sensitive. Now found escaped in coastal habitats of
Central and South Florida, through the Keys. It is also naturalized
in the Bahamas and possibly in other parts of tropical America.
The seeds are dispersed by birds and by water. Fruits may float
for up to one year, and can be spread along wrack lines of the
coast, canal banks, mangroves and inland shorelines.
Why beach naupaka must be managed
Shrubs of beach naupaka produce copious fruit clusters and can
grow to heights of 5 meters (16 feet). They displace native dune
vegetation, including sea oats, that helps to guard against
erosion. This shrub consumes open spaces on the dune that are
important for the endangered sea lavender (Argusia gnaphalodes),
beach peanut (Okenia hypogaea), beach clustervine (Jacquemontia
reclinata), and threatened inkberry. Because of its rapid growth
and expansion, some municipalities have authorized the removal of
beach naupaka within 10 years of planting. Beach naupaka is
difficult to control. The fleshy branches are easy to handpull, but
broken underground stem segments readily resprout if not completely
removed. Herbicides have been effective in the dry dunes, but
removal and treatment of beach naupaka in tidal mangrove areas
requires more careful treatment. Monitoring and re-treatment are
necessary for at least two to three years after removal, to weed
out new seedlings and stem sprouts.
naupaka (Scaevola taccada)
Image Credit: W. Jurgens, courtesy of Fairchild Tropical Garden