Weeds in our Area (Part One Hundred and Forty One)

By Bob and Ena McIntyre – Garden Route Region.

UPDATED LIST: Araujia sericifera (Motvanger, Moth catcher)

The Moth catcher occurs throughout South Africa and problem areas extend in a swathe running from Gauteng province south-eastwards to the KZN coast as well as pockets of infestation in the coastal regions of the Eastern and Western Cape. Luckily there are very few in evidence around Wilderness. That certainly does not mean that the moth catcher can be ignored locally - plants don’t need legs to get around. Araujia sericifera has been a category one invader since the original invasive species list was published and for very good reason as you’ll see below. The plants, native to Peru were introduced as ornamentals.

Description: Araujia sericifera is a fast-growing vine with milky juice. Plants often thrive in citrus groves – possibly the reason for Lesley Henderson noting it as a problem in the Eastern Cape where the citrus industry is significant. Plants grow extremely fast. Vines can grow over tree canopies within a couple of years and kill individual branches by strangling. Stems are twining, slender, slightly woody and sometimes branched. The mature stems can be up to 5 metres long. Leaves are opposite, narrowly triangular in shape and smooth. The leaves are dark green above, pale underneath with very short dense hairs. The clusters of fragrant cream or pale pink flowers appear from November to April and often have a maroon streak inside. Insects do the pollination and the seeds are ultimately wind-dispersed. The large pendant shape seed-pods are spongy to the touch, pale grey-green and open to release numerous seeds at maturity. The seeds are dark brown to black, 5-6 mm long, with numerous silky white, deciduous hairs attached at the apex. Plants reproduce by seed from the very first season of growth and vegetatively from severed underground stems or crowns.

Invasive Status: Araujia sericifera is a declared weed – Category 1b on the updated list and invades gardens, urban open space, water courses, forest clearings and plantations. It will quickly smother desirable trees and other plants. In addition the whole plant is poisonous.

Control: There are no registered herbicides or specific control methods for the species at this time. The best option is to look out for seedlings and to uproot these without delay

References: ALIEN WEEDS AND INVASIVE PLANTS: Lesley Henderson Copyright @ 2001 Agricultural Research Council. Problem Plants of South Africa – Clive Bromilow. www.wikipedia.org