Control of the invasive liana, Hiptage benghalensis

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‚à í1). The foliar-applied herbicides were only effective in controlling the hiptage seedlings. Of the foliar herbicides trialed, dicamba, fluroxypyr, and triclopyr/picloram controlled \u3e75% of the treated seedlings. On the larger plants, the cut stump applications were more effective than the basal bark treatments. Kills of \u3e95% 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‚à í1), excluding labor, would be $A14‚Äâ324‚Äâha‚à í1 using picloram and $A5294‚Äâha‚à í1 and $A2676‚Äâha‚à í1, respectively, using glyphosate and fluroxypyr. Foliar application using dicamba for seedling control would cost $A1830‚Äâha‚à í1. 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 (\u3e98%) of the viable seeds, a low viability (0%) of 2‚Äâyear old, laboratory-stored fruit, and a seedling density of 0.1‚Äâseedlings‚Äâm‚à í2 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