Weed Control of Sugarcane

Sugarcane is a perennial crop and remains 3-4 years in the same field. Therefore, all types of weeds, seasonal, annual and perennial grow in the field. These compete for nutrients, space, light and create a favourable environment for disease and insect development. Weeds which emerge only during rainy season are Echinochloa colonum and E. crusgalli (grasses), Dacryloctanum  aegyptium (makra), Amaranthus viridis (cholai) and Celosia argentia (safed murg). Their rate of growth is very high. Weeds which emerge before the start of monsoon are Cyperus rotundus (motha), Cynodon dacrylon (doob) and Sorghum halepense (banchari) and some annual weeds like Chenopodium album (bathua), Lathyrus sativa (matri), Vicia spp. (ankrni), Angallis arvensis (krishna Neel) and Fumaria parviflora (gajri).

Weed control in sugarcane is done by adopting mechanical method or chemical method

1. Mechanical method: Fields are given a hoeing with help of kurpi or spade, after a month of sowing and the process is repeated frequently. This method not only removes the weeds but also increases the sprouting and tillers and destroys insects and enhances aeration in the soil. Some growers make best use of this laborious operation by cultivation of second crop in between the sugarcane crop as a mixed crop.

2. Chemical method: Weeds of the sugarcane can be classified into two groups i.e. one with broad leaves or dicotyledonous and second as narrow leaved grassy or monocotyledonous. Spraying with 2-40 @ I kg in 800 litres of water after a month of sowing destroys all broad leaved weeds like 'bathua', matri, krishna neel, gajri, motha, cirola; etc. The second group of grassy weeds, are really a most problematic, since sugarcane crop belongs to the grassy group of monocotyledonous. Hand hoeing is the best method to control these weeds. Sometimes, pai1icularly when the field is sown afi'esh, spraying with 2 kg of Dilapon or Paraquat in 500 litres of water is done before the sprouting of the sugarcane crop appears. This kills all grasses that stand in the field at that stage. Sometimes spraying is done with 2 kg Atrazine or Simazine in 500 litre water after the sprouting of the sugarcane crop to check the weed's growth and spread. This is done with utmost care that a minimum dose, of weedicide (sub-lethal), falls on the sugarcane crop and optimum dose (lethal doze) falls on the weeds.