Distribution, density, and abundance of parthenium weed (parthenium hysterophorus L.) at Kuala Muda, Malaysia

Knowledge of distribution, density, and abundance of weed in a place is a prerequisite for its proper management. Parthenium hazard is a national agenda in Malaysia, and Kedah is the worst infested state in the country. Despite it, the distribution and abundance of the weed is not systematically documented. Periodical weed surveys were conducted at Kuala Muda, Kedah, during March and September 2015 to identify infested locations, to determine density, abundance, and severity of infestation, and to do mapping of weed distribution of the area. Geographic locations were recorded using a GPS. Weed density was measured following the list count quadrat method. (e mapping of weed infestation was done by the ArcGIS software using data of GPS and weed density. Different letters were used to indicate the severity of infestation. Results indicated that in Kuala Muda, sixteen sites are infested having average weed density of 10.6 weeds/m2. (e highest density was noted at Kg. Kongsi 6 (24.3 plants/m2). (e relative density was highest at Semeling (27.25%) followed by Kg. Kongsi 6 (23.14%). (e average severity of infestation was viewed as the medium. Parthenium abundance and relative density increased by 18.0% and 27%, respectively, in the second survey conducted. (e intervention of concerned authority to tackle the weed problem using integrated weed management approach is emphasized.