Ronstar Herbicide

A safe rotational option for pre-emergent weed control this autumn.

Ronstar is a selective, pre-emergent herbicide for control of many annual grasses and broadleaf weeds in warm season turf and ornamental plants. Ronstar is registered for use in a variety of recreational turf situations including sportsfields, fairways, golf tees and industrial and commercial lawns. Ronstar is also registered for the control of a range of weeds in container grown woody ornamental shrubs, trees and vines.

Ronstar – Key Turf Benefits

Ronstar herbicide controls weeds through shoots, not roots. So unlike competitive products that don’t distinguish between roots of weeds and roots of desirable plants, Ronstar doesn’t harm healthy turf. This product can be applied to sensitive grasses and areas where roots are already weakened by the following;

• High traffic areas (eg. soccer goalmouths).
• Pest injury.
• Stressed growing conditions such as drought or nutrient imbalances.
• Renovation or scarification activities.

Ronstar is ideal for use on Warm-Season Grasses

• One pre-emergent application – even in cold weather, or weeks before seed germination – controls weeds all season long.
• Offers an environment conducive to sprigging. Proven not to harm establishing warm season turf plants.
• Doesn’t inhibit turf root growth or recovery from damage.
• Doesn’t prevent roots from tacking down, unlike Group D Herbicides.

Ronstar’s Unique Mode of Action and its importance in Weed management
Ronstar has a unique mode of action. It is a Group G herbicide. Oxadiazon inhibits the plant enzyme protoporphyrinogen oxidase. This enzyme is critical in the production of Chlorophyll in plants. When susceptible weeds come into contact with oxadiazon, chlorophyll production is restricted, and as a result, photosynthesis cannot occur. Without food reserves from photosynthesis, the emerging weed dies. Ronstar is the only pre-emergent herbicide with this mode of action in turf. Most other pre-emergent herbicides belong to the Group D class. Ronstar offers a unique capacity to rotate between mode of action groups. With resistance reported to DNA (Dinitroanilines) pre-emergent herbicides in the US market, the need to alternate mode of action is more important than ever. Particularly when dealing with common grass weeds such as Wintergrass and Crowsfoot.

Ronstar is Non Volatile

Volatility is the process by which a herbicide changes from the liquid or solid state to the gaseous or vapor state. Once in the vapor state the herbicide is rapidly lost from the intended area of application and poor weed control or injury to non-target plants can occur. Oxadiazon is not considered to be volatile and will not have losses. Other DNA (Dinitroaniline) pre-emergent herbicides are susceptible to volaltilisation and can result in a significant reduction in activity when climatic conditions are not ideal.
Oxadiazon is a moderately persistent herbicide with a half-life of three to six months. It is strongly adsorbed to soil colloids and does not readily leach.

Safety around Ornamentals

Unlike many pre-emergent herbicides, Ronstar is safe around ornamentals. If when applying Ronstar, you find spread onto garden beds, it is very unlikely to cause you any problems. Irrigation after the application will negate any issues. Other pre-emergent herbicides can cause significant injury when overspray or spread into garden bed occurs.  Ronstar has been proven to be safe on over 68 genera of ornamental plants.

Weeds Controlled with Ronstar

Key Broadleaf weeds: Bittercress, Creeping Oxalis, Petty Spurge, Sorrel, Sowthistle, Trefoils.

Key Grassy weeds: Winter Grass, Crowsfoot, Summergrass.

For more information on Ronstar or assistance with weed identification, send an email to jyri.kaapro@envu.com or contact any member of our team.

Always read the label before use.

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