Weed management practices in apple orchards and vineyards in the South Island of New Zealand

A survey of weeds and weed management practices was conducted during 1997/98 in apple orchards and vineyards of Canterbury and Nelson/Marlborough regions of New Zealand. According to growers, mallow ( Malva spp.) ranked as the most widespread weed in apple orchards of both regions. In vineyards, mallow was the most common weed in Nelson/Marlborough and the second most common weed in Canterbury. Other dominant weeds in Nelson/Marlborough included grasses, black nightshade ( Solarium nigrum) , fathen ( Chenopodium album ), and redroot ( Amaranthus retroflexus ). In Canterbury, grasses, clovers, fathen, and thistles were common. In almost all orchards knockdown herbicides were used but the use of residual herbicides varied. The total number of herbicide applications/year has increased in both regions over the past 10 years, but the proportional use of residual herbicides has declined. Some other weed management practices are used in orchards but a sound integration of these is commonly lacking.