Noxious weeds usually possess some characteristics in common, e.g., rapid multiplication, adaptation to changing circumstances, high competitive ability, and resistance to control measures. Dormant tubers of Cyperus rotundus L. which are small and hard to identify make the weed a serious one in the same way as a piece of rhizome of Imperata cylindrica (L.) Raeuschel in the soil. The tuber or rhizome under unfavourable conditions stays dormant underground. With its high competitive power and resistance to most preemergence herbicides plus its irritating hairs on leaves when touched, Rottboellia cochinchinensis (Lour.)Clayton is considered to be very serious in any crop.
Management of weed species mentioned above is discussed in the paper.