In‐transit shipboard fumigation of pine woodchips to control Bursaphelenchus xylophilus

Woodchips from several pine species, infested with the pine wood nematode, Bursaphelenchus xylophilus, were treated in transit using phosphine fumigant. Using aluminum phosphide tablets producing 4 g m−3 phosphine, the percentage of infested samples was reduced from 79 to 6% during the voyage from the USA to Sweden. Temperatures in the periphery of the cargo were lower than in the center, and the fumigation was less effective in the periphery. Phosphine concentration had declined to nearly zero before arrival of the chips in Sweden and posed no safety threat to workers or the ship's crew.