Brisbane Rainforest Action & Information Network


Dutchman's pipe vine (Aristolochia elegans)

Kenneth McClymont

Dutchman’s pipe vine is a vigorous exotic vine that originates from Brazil in South America. This vine typically grows in protected situations with high humidity, in full to medium light. It has been (and still is) cultivated as an ornamental plant in suburban gardens but has turned ‘garden escapee’ and over time has spread into bushland, including local rainforest remnants.

You will most commonly notice this plant growing around the edges and in disturbed gaps of local rainforest remnants, especially along creeks or in moist gullies. Dutchman’s pipe vine climbs over and smothers remnant rainforest species with its masses of foliage, thereby degrading the structure of, and reducing species diversity within, local remnants.

Dutchman’s pipe vine is also known to be fatally attractive to the Richmond Birdwing butterfly (Ornithoptera richmondia); a large and spectacular butterfly once common in the Brisbane region.

Unfortunately, female butterflies find the foliage of Dutchman’s pipe vine extremely attractive as a food plant for their larvae. Richmond Birdwings are known to lay their eggs on the foliage of Dutchman’s pipe vine even in preference to their native food plant (Birdwing vine - Pararistolochia praevenosa) where the two occur together. The result is that the emerging hungry larvae are quickly poisoned by the toxins in the leaves of Dutchman’s pipe vine thus restricting successful re-establishment and expansion of viable Richmond Birdwing populations.

Locally, the Richmond Birdwing is totally dependent on a single native rainforest vine - Birdwing vine (Pararistolochia praevenosa, formerly Aristolochia praevenosa) as a food plant for its larvae. This vine naturally occurs in lowland subtropical rainforest communities. Unfortunately, this rainforest type has been cleared almost to extinction in South-east Queensland, which means that the Birdwing vine and the dependent Richmond Birdwing butterflies have become extinct in about half to two-thirds of their former range.

Dutchman’s pipe vine is recognised by its broad, heart-shaped leaf with a distinct curved leaf base. Leaves are arranged alternately along the climbing stem and can be up to 12 cm long. The under surface of the leaf is a distinct pale grey-green with a waxy lustre. Stems of young vines are slightly channelled and corky, whilst larger vines are covered with a fissured corky or spongy brown bark that can be easily rubbed off. Vines up in the canopy can be hard to identify if a leaf sample is unavailable - if in doubt scratch the bark. The damaged stems of Dutchman’s pipe vine exude a strong smell, not unlike acetone (nail polish remover).

Flowers appear in summer, are a distinctive and attractive reddish purple with white and yellow splotches, and are shaped like a
(Dutchmans) pipe – hence the name. Flowers are approximately 7cm long and arise from the leaf axils.

Another distinctive identification feature of this vine is the fruit - a segmented papery capsule (up to 6cm long) which opens like an upside down parachute and can remain attached to the vine stem for some time after opening. Each capsule contains around 350 papery, tear shaped seeds which are spread by wind or water (when growing along creeks).

Management

Although several methods are available, this plant can be difficult to control. Manual removal is possible. Seedlings and young plants can be hand-pulled and small infestations of larger vines can be dug out. Dutchman’s pipe vine is known to root at each stem node, so digging out a large vine could cause a lot of disturbance to adjacent native seedlings.

Herbicide can also be used to combat this species. Canopy vines can be cut first at chest height and vine stems left in the canopy to die. For smaller diameter vines make a second cut closer to the ground just above the first rooting node and immediately apply a Glyphosate-based herbicide (Roundup) to the basal stem cut. On larger vines, it is more effective to cut and scrape along the basal section of the stem (back towards the main root) and then apply herbicide to the scraped stem section. This increases the surface area of exposed plant vascular tissue available for absorption of the applied herbicide. For all cut stem applications use a herbicide dilution of 1:1 (1 part herbicide mixed with 1 parts water).

Foliar spraying is usually ineffective against large vines because leaves are covered by a waxy cuticle preventing herbicide
penetration. However, young plants and regrowth shoots are more susceptible to spray application and may be killed or seriously weakened. For foliar spraying, use a Glyphosate-based herbicide at a dilution of 1:50.

If vines cannot be dealt with immediately and are within reach, it would pay to collect, bag and remove the seed capsules of this vine from the site….

…One year's seed equals seven years' weeds??

References

McDonald, G.J., (1998) Growing a butterfly garden in South east Queensland.

Bower, S., (1998) Weed Sheet No. 10 What’s eating your remnant? Dutchmans pipe in Big Scrub Rainforest Landcare Group Newsletter March 1998.

Newsletter 12, June 1998

Updated 8 June, 2002