Weed Problems of Grazing Lands and Control of Some Problem Weeds in the Markham Valley of Papua New Guinea

Abstract

Weeds are a serious problem in this region during both the establishment of pastures and their productive period, causing serious reduction in growth, vigour, productivity and persistence. Factors responsible for weed infestation and possible methods of prevention and control are outlined in this paper. The biology and weed Ecology of Cassia alata, Digitaria insularis, Jatropha gossypifolia, Mimosa spp, Sida spp, Solanurn rnauritianurn and Solanum torvum are briefly described and detailed recommendations are given for the control of these weeds.

Biology, distribution and management of the invasive Jatropha gossypiifolia (Bellyache bush): A global review of current and future management challenges and research gaps

“…Research has shown that one of the most common and effective methods to control J. gossypiifolia is with the use of herbicide application (Bebawi et al, 2011;Chadhokar, 1978;Pitt and Miller, 1991;Vitelli and Madigan, 2002;Vitelli et al, 1988; Table 3). Previous research has shown that cutting J. gossypiifolia at stump level and then applying 2,4,5-T in diesel, picloram and 2,4,5-T in water, in conjunction with a basal bark application consisting of picloram and 2,4,5-T in diesel can be 90%-100% effective at controlling the species (Chadhokar, 1978;Pitt and Miller, 1991). A further study by Vitelli et al (1988) also showed that treating cut stumps with either 2,4-D and picloram, fluroxypyr, triclopyr or neat diesel, were all very effective methods for controlling J. gossypiifolia.…”

“…Research shows that J. gossypiifolia can reduce the proportional thickness of its leaves and close its stomata in response to changing climatic conditions, which is likely a key attribute allowing the species to survive across a range of climatic regions or in periods of extreme weather patterns such as drought (Rengifo et al, 2002;Tezara et al, 1998). Previous research and attempts to control J. gossypiifolia have been focused on biological control (Bebawi et al, 2007a;Dhileepan et al, 2014;Heard et al, 2012;Snow et al, 2016;Taylor et al, 2017), creating competitive pastures (Bebawi et al, 2013), fire management (Bebawi and Campbell, 2002a;Bebawi and Campbell, 2002c;Guterres Ada et al, 2008), herbicide application (Bebawi et al, 2011;Chadhokar, 1978;Csurhes, 1999;Pitt and Miller, 1991;Vitelli and Madigan, 2002;Vitelli et al, 1988) and mechanical control (Bebawi and Campbell, 2002b;Guterres Ada et al, 2008). Although promising controls have been developed, many have shown varying success rates as a single treatment, whilst a majority of the identified global research on control has been conducted in either Australian or Papua New Guinea populations (Bebawi et al, 2013;Bebawi et al, 2011;Heard et al, 2012).…”