Weed Management

Introduction to Weed Management

  • Unchecked weed growth in sugarcane has caused yield losses to the extent of 15-70 percent depending upon the nature, density and time of weed infestation.
  • Even if the yield reduction due to weeds say 10 percent the loss in cane and sugar yield in the country per annum may be around 25 million and 2.5 million tons respectively
  • Weeds reduce the yield of sugarcane by intoxicating the soil with their harmful root secretions and by spreading by their root system in soil earlier than sugarcane crop.
  • Nature of weed problem in sugarcane is different from other crops due to 1) adoption of wider spacing (60-130cm) 2) Slow growth rate in the initial crop growth 35-45 days for complete germination and another 60 days for full canopy development, 3) intensively irrigated crop, hence no dearth for moisture, 4) highly fertilized crop, 5) less preparation of land if it is a ratoon crop.
  • Estimates showed that the uptake of nutrients by weeds furing the first seven weeks of crop stand may be about four times of N and P and 2.5 times of K over sugarcane crop.
  • Weeds in sugarcane may remove as much as 750-1250 tonnes of water with a transpiration coefficient ratio ranges from 500 to 1200.
  • Critical period of weed competetion in sugarcane is the first 90 days of crop growth.
  • Weeds present in cane rows cause much harm than those present between rows

Common weeds in sugar cane


  • Cyperus rotundus


Cynodon dactylon
Sorghum helepense
panicum spp.
Dactyloctenum aegyptium

Broad Leaved Weeds

Chenapodium alloum
Convolvulus arvensis
Amaranthus viridis
Portulaca oleraceae
Commelina bengalensis
Triantherma portulacastrum

Weed control schedule for pure and intercropped cane

Crop Sequence Weedicide Rate (Kg/ha) Time of spray Remarks
Autumn cane alone Simazine followed by 2, 4-D in winter twice 2 kg

1 Kg


Pre emergence

20-25 days

60-70 days

Controls all winter weeds except cyperus. 2, 4-D controls cyperus to a great extent
  Dalapon 5 Kg As spot treatment during summer Dalapon is used to control grassy weeds like Sorghum halepense and Cynodon dactylon etc.
Cane +Mustard

Cane + Pea

Cane + Gram

Tok - E-25


3 Litre

4-6 Litre


3 Litre




Winter weeds are removed once in pea and gram manually
Cane + Potato Tok - E-25




4-6 litre

1 Kg a.i.

2.5 Litre

At early emergence of weeds at the initial stage of germination in cane and potato Earthing may not be done in potato and therefore, planting on potato should be on heavy ridges

Weed control schedule in spring-planted sugarcane

Crop sequence Weedicide Rate (Kg/ha) time of spray
Cane alone Simazine




At pre-emergence and after earthing
Cane + Urad Simazine followed by 2, 4-D 2.0


At pre-emergence 2,4-D at 20-25 days and then 60-70 days.
Cane + Moong Tok-E-25



4-6 Litre

3 Litre

At pre-emergence followed by grammaxone @ 2.5 litre/ha after harvest of intercrops as spot treatment.


Weed Control methods

Mechanical methods

  • Removal of weeds on bunds, nearby waste lands to arrest the spread of the same.
  • Removal of weeds by hand pulling, hoeing, ploughing, harrowing, discing etc.
  • Blind hoeing, interculture and earthing - up are the main operation performed before germination, during tillering and at maximum tillering stages respectively.
  • The main objective of hoeing and interculture is to control weeds, to minimise evaporation and to increase aeration in root zone.
  • Destruction of underground parts by ridging, deep ploughing and puddling etc.

Cultural methods

  • Adopting crop rotation (Rice followed by sugarcane)
  • Growing intercrops competing effectively with weeds (short duration quick growing and smothered crops like pulses)
  • Mulching (using sugarcane trash)
  • Clean cultivation
  • Trap cropping

Chemical methods

  • Pre-emergence and post-emergence application of 2,4 - D at 1.0 to 1.5 Kg/ha - to control dicots and broad leaved weeds
  • Pre-emergence application of simazine at 2 kg/Ha - to control both monocot and idcot weeds.
  • Dalapon @ 0.5 kg/ha followed by grammaxone @ 2.5 litre / ha would control grassy weeds.
  • Pre-emergence application simazine and 2,4 - Damine @ 2.0 Kg / ha each to control monocots and dicots.
  • Tank mixture of dalapon @ 5 kg/ha + 2,4 - D @ 1 kg/ha would control grassy weeds including cyperus.
  • One weeding and one post emergence application of isoproturcon at 0.95 kg a.i/ha gave increased care yields.

Time of herbicide application

  • Pre-emergence application of herbicides is done soon after planting on the third or fourth day.
  • For controlling turning weeds like Ipomea spp application of Atrazine or Metribuzin (Sencor) may be done after final earthing up around the cane rows.

Use of herbicides in inter cropped sugarcane

  • Alachlor and linuran are useful herbicides to control weeds where sugarcane intercropped with pulses, oilseeds and potato.
  • Oxyfluorfen (Goal) at 0.3 Kg a.i/ha as pre-emergence spray is useful when pulse is intercropped with sugarcane.

Integrated weed management

  • Deep ploughing to remove perennial weeds, to bury weed seeds deep.
  • Repeated tillage operations before planting to reduce weed growth before planting.
  • cleaning of irrigation channels, using clean sugarcane setts, checking seeding of weeds, and using of well decomposed FYM or compost to prevent weed spread.

  • Pre-emergence herbicide application to check weed growth during the critical crop stage.
  • Post-emergence herbicide application to check persisiting broad leaved weeds.
  • Interculture coupled with hand weeding to remove left over weeds.
  • Intercropping and mulching to smother weeds in between cane rows.
  • Crop rotation to suppress dominant weed flora.
  • fallowing the land to expose, activate hidden weed seeds and then destray them.