Seed germination characteristics and control options for Noogoora bur (Xanthium strumarium) in commercial maize production

Abstract

Noogoora bur (Xanthium strumarium) is a large, herbaceous, highly competitive annual weed of arable and horticultural crops which is subject to Regional Pest Management Plans in the Waikato and Bay of Plenty regions, New Zealand. A study with scarified burs showed that most plants emerged from 0-40 mm and none from 100 mm depth. Plants emerged after 8 days from 0-30 mm, after 14 days from 90 mm and continued to emerge over summer, with some also germinating in the second year after initiation. Cultivated fallow resulted in germination of similar numbers of seeds over two growing seasons with no new seed input. Results from a field trial showed that dicamba and atrazine, alone or in combination with other products, as well as topramezone, provided good control of this weed in maize crop.