Control of the invasive liana Hiptage benghalensis
Vitelli J; Madigan B; Van Haaren P; Setter S; Logan P
Weed Biology and Management
The liana hiptage (Hiptage benghalensis) is currently invading the wet tropics of northern Queensland and remnant bushland in south-eastern Queensland Australia. Trials using seven herbicides and three application methods (foliar basal bark and cut stump) were undertaken at a site in north Queensland (158‚Äâ700‚Äâhiptage plants‚Äâha‚àí1). The foliar-applied herbicides were only effective in controlling the hiptage seedlings. Of the foliar herbicides trialed dicamba fluroxypyr and triclopyr/picloram controlled >75% of the treated seedlings. On the larger plants the cut stump applications were more effective than the basal bark treatments. Kills of >95% were obtained when the plants were cut close to ground level (5‚Äâcm) and treated with herbicides that were mixed with diesel (fluroxypyr and triclopyr/picloram) with water (glyphosate) or were applied neat (picloram). The costings for the cut stump treatment of a hiptage infestation (85‚Äâ000‚Äâplants‚Äâha‚àí1) excluding labor would be $A14‚Äâ324‚Äâha‚àí1 using picloram and $A5294‚Äâha‚àí1 and $A2676‚Äâha‚àí1 respectively using glyphosate and fluroxypyr. Foliar application using dicamba for seedling control would cost $A1830‚Äâha‚àí1. The costs range from 2-17 cents per plant depending on the treatment. A lack of hiptage seeds below the soil surface a high germinability (>98%) of the viable seeds a low viability (0%) of 2‚Äâyear old laboratory-stored fruit and a seedling density of 0.1‚Äâseedlings‚Äâm‚àí2 12‚Äâmonths after a control program indicate that hiptage might have a short-term seed bank. Protracted recolonization from the seed bank would therefore be unlikely after established seed-producing plants have been controlled.