ProForce Duke Herbicide.

ProForce Duke herbicide is a powerful selective herbicide made specifically for turf grass. This product from Indigo Specialty, is an alternative to Destiny herbicide, and contains iodosulfuron-methyl. This means you get the same great results and save money.

• It has a broad spectrum of weed control in a single pass solution. Weeds it controls include Winter Grass, Onion Grass and ryegrass.
• It has a high level of safety on couch, kikuyu and most Buffalo varieties.

Key Facts About Duke Herbicide.

• Active: It contains 100 g/Kg of Iodosulfuron-methyl.
• Chemical Group: It is a sulfonylurea herbicide and is in HRAC Group 2. This group also contains ProForce Recondo and Envu Tribute.
• Type: It is a selective post emergent herbicide.
• Pack Size: Available in 50 g, 100 g and 500 g packs.
• Safety: Safe on most grass varieties.

This is a good option from a resistance management rotational perspective for broadleaf weeds.

Table of Group 2 Turf Herbicides.

How Does Duke Work?

ProForce Duke stops a key enzyme in weeds. This enzyme is called acetolactate synthase (ALS), and plants need this enzyme to produce important amino acids.

When it blocks this enzyme, weeds can’t grow properly and they die, with it taking 2 to 3 weeks to see the full results. This is a slow acting chemical but very effective.

Key Uses for Duke Herbicide.

Duke excels in two areas:

• As a transition aid to remove ryegrass out of warm season turf like Couch.
• To control Onion Grass.

Duke for Transition.

What is Ryegrass Transition?

Ryegrass transition is when you remove temporary ryegrass from warm season turf. This happens every Spring when:

• Ryegrass starts to compete with couch as it comes out of Winter dormancy.
• You want warm season turf to dominate the grass cover over the Summer.

Why Transition Matters:

• Ryegrass competes with couch for nutrients, light and space.
• A mix of grass types looks patchy and uneven.
• In sports grounds over the Summer couch can cope with wear better.
• In the Summer heat ryegrass weakens, and can leave bare patches.

Why Use Duke Herbicide to Transition?

Duke is uniquely effective for ryegrass transition because:

Selective:

Duke kills ryegrass but is completely safe on couch. This selectivity is crucial to enable a smooth transition.

Perfect Timing:

• Apply Duke in the early Spring once temperatures start to increase. This is because:
• The ryegrass is still actively growing.
• The couch is starting to break dormancy.
• Weather conditions favour the activity of this herbicide.

Clean Results:

Duke gives:

• The complete removal of the ryegrass.
• No damage to the couch grass.
• A very smooth Smooth transition without any bare patches.
• Professional results.

When to Apply Duke Herbicide for Transition.

The ideal Window:

• Between August to October in most Australian regions.
• When the soil temperature is from 12 to 15°C.
• Before the couch becomes fully active.
• While the ryegrass is still green and growing.

When to Transition:

• You start to see couch shoots.
• The ryegrass is still actively growing.
• The daytime temperatures are consistently above 18°C.
• 6 to 8 weeks before the peak of Summer.

Regional Timing Guide:

Northern Australia: July to August.
Central Australia: August to September.
Southern Australia: September to October.
Cool areas: October to November.

Duke Herbicide Transition Success.

Professional turf managers report great results when they use this to transition out ryegrass:

• It removes 95 to 100% of the ryegrass when you use it correctly.
• Zero couch damage at label rates.
• A clean transition in 3 to 4 weeks.

Transition Protocol.

One to two weeks before you plan to transition:

• Feed the couch to encourage it.
• Gradually reduce the height of cut.
• Make sure that there is good soil moisture.
• Check the weather forecast.

When you use it:

• Use Duke at 100 to 125 g/Ha.
• Add a non-ionic surfactant at 0.25 %. We suggest Optispread. Do not use a spray buffer as Duke works best at a water pH of around 7.
• Use it in calm, mild conditions.
• Ensure you get even coverage.
• You can mix it with Vertmax Duo turf pigment and Vertmax pigment to hold heat and give a quicker result.

Post-Use. Two to Four weeks after use.

• Due to it being “sticky” it can leave a residual in a spray tank. We recommend the use of Tank Aid to clean any residual out of the tank.
• Avoid any heavy traffic.
• Continue regular watering.
• Don’t fertilise for 2 weeks.
• Monitor the couch emergence.

Follow-up Care.

• Fertilise normally after 4 weeks
• Gradually return to the usual height of cut.
• Overseed any thin areas if you need to.

Duke Herbicide vs Onion Grass.

Why Onion Grass is So Hard to Kill?

Onion grass (also called Guildford grass) is one of the toughest weeds to control in turf. This weed has several features that make it hard to control:

• A deep root system.
• It has waxy leaves, that repel most herbicides.
• It is active over the Winter when grass is dormant.
• This weed spreads fast.

How Duke Beats Onion Grass.

Duke is very effective against Onion Grass. Here’s why it works so well:

Systemic Action:

• Duke moves through the whole plant. This includes the roots and bulbs, and kills the Onion Grass completely.

Perfect Timing:

• Onion grass emerges in the Autumn and then grows through the Spring. This matches perfectly with the usage timing for Duke herbicide.

Selective Control:

• Duke kills Onion Grass without any damage to couch, kikuyu, or most buffalo varieties.

Long-lasting Results:

One application can control Onion Grass for the entire season when you use it correctly.

Duke Success on Onion Grass.

Many users report 100% control of onion grass with Duke. The key is:

• Use this when the Onion Grass is actively growing
• Use the correct rate for your turf type.
• Add a surfactant for better uptake. We suggest Optispread.
• Be patient for 2 to 3 weeks to see the full results.

What Weeds Does Duke Herbicide Control?

Duke controls a wide range of problem weeds in turf:

Broadleaf Weeds:

• Bindii. A painful lawn weed with spiky seeds.
• Black Thistle. A tough perennial weed.
• Cat’s Ear. A dandelion-like weed.
• Cotula. A small daisy-like weed.
• Cudweed. This is a grey-green Winter weed.
• Medic. This looks like clover.
• Mouse Ear Chickweed. This forms thick mats that choke out turf.
• Oxalis.
• White Clover. A common lawn weed.

Grass Weeds:

• Ryegrass. This gives excellent control against this, and is ideal for transition from couch.
• Guildford Grass (Onion Grass). A main target weed
• Winter grass. Duke only suppresses this
• Bahia Grass. This only suppresses and reduces the amount of seedhead.

How Safe is Duke Herbicide on Turf?

Safe Grass Types:

• Couch Grass (Common and Hybrid) – Very safe
• Kikuyu Grass – Very safe
• Buffalo Grass – Safe on most varieties
• Zoysia – Generally safe (check the label).

Grass Types to Avoid:

• Queensland Blue Couch – DO NOT USE.

If you have questions or concerns about the use of Duke, please feel free to contact a sports turf consultant or turf agronomist.

Duke herbicide Label

Duke SDS