Why consider making a switch to HighNoon™ herbicide?

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HighNoon™ herbicide is a new option for broadleaf weed control in rangeland, pasture and non-crop lands. For ranchers and land managers who have relied on other products over the years, it can be hard to know whether it makes sense to switch to a new herbicide like HighNoon, and what the advantages may be. HighNoon works in the same settings and provides similar efficacy to legacy products like Tordon® 22K and Milestone® herbicides, so when and why does it make sense to change up your approach?

HighNoon herbicide profile

HighNoon includes the first new active ingredient (Rinskor® active) available for rangeland and pastures in nearly 15 years. HighNoon combines Rinskor with the active ingredient in Milestone (aminopyralid). Rinskor works by attaching to a new binding site on plants for a new mode of action with some additional benefits in lower use rate, broader spectrum and improved environmental fate. Because it works selectively, HighNoon helps maintain desirable vegetation in the field. This profile makes it a simple – and beneficial – replacement in a lot of rangeland and pasture weed control programs.

If you’re currently using Tordon® 22K herbicide...

If you’re applying Tordon® 22K herbicide, it’s probably because you need serious control of noxious and invasive weeds. HighNoon™ herbicide offers that same level of control on many species, but with a little more flexibility, while going easier on desirable vegetation. While Tordon 22K is safe on grasses, the grass safety profile for HighNoon is actually better — even at 4X labeled rates. This makes HighNoon a good option when there’s overlap in spot treatment, to prevent areas of damage that can then become hospitable to invasives, cheatgrass and weeds.

Although in most cases you won’t need to, you can use Tordon 22K with HighNoon. HighNoon can be tank-mixed with lower rates of Tordon 22K to add a new site of action to your program while maintaining some selectivity to desirable vegetation. HighNoon also gives you more application flexibility. Unlike Tordon 22K, HighNoon can be sprayed up to the water’s edge.

If you’re currently using Milestone® herbicide...

HighNoon™ herbicide starts from a better baseline than Milestone® herbicide. Think of it this way: Anything Milestone can do, HighNoon can do better. With HighNoon, you get a more complete, faster kill thanks to Rinskor® active. That means you get your land back quicker.

Land managers and ranchers are also finding HighNoon is a more cost-effective way to get your aminopyralid on the ground. With a new site of action through Rinskor, HighNoon provides a wider spectrum of control compared to Milestone, so you can use it to control more weeds even with a reduced-risk herbicide. Finally, there are several convenience features for HighNoon versus Milestone. HighNoon comes in a galon container, versus quarts of Milestone, so there’s less packaging to handle when you’re treating large areas. HighNoon also offers more room for error in measuring and spraying at low levels compared to Milestone, where measurements have to be very precise, particularly at the 5-7 oz. levels, or there is risk of damage to desirables.

If you’re currently using Chaparral herbicide and/or Opensight® herbicide...

You may be adding Escort XP for additional control with these products. With Chaparral™ and Opensight® herbicides, you’re locked into the ratio of Escort XP you can use. But with HighNoon™ herbicide, you can prescribe the correct rate of Escort XP or Telar you need for your acre.

HighNoon is a liquid, so it’s easier to handle than the granular formulations of Chaparral and Opensight. Rinskor® active in HighNoon increases burndown and early activity versus Chaparral and Opensight, and compared to Milestone® herbicide, HighNoon provides a more complete, faster kill.

If you like adding Plateau and indaziflam for annual grasses...

The most expensive component of weed control is the time it takes to spray. When you use HighNoon herbicide along with Plateau or indaziflam, you can control broadleaves and invasive grasses together in the same pass, giving desirable grasses the best chance to compete for the land. This combination application may not need more than two years of control before desirable grasses can out-compete annual grasses.

Because there is no way to know what broadleaves could be in the seedbank until the following year, getting them under control proactively is important. The same is true with desirable grasses: You don’t know what’s there if they have not been released. Using a short residual product mix first (like Plateau plus HighNoon), or HighNoon alone in the spring, can protect desirables while knocking out broadleaves.

Using HighNoon also allows you to introduce more modes and sites of action, which is especially helpful when combating multiple flushes of annual grasses at various growth stages through the season. HighNoon has activity at pre-germination and boot/infloresence, while Plataeau’s activity is mostly post-germination. Indaziflam is only pre-germination on annuals.

In non-crop areas, HighNoon can be used at a rate of up to 40 fl oz per acre for effective and lasting control. This is especially useful and efficient when you need to keep areas like roadsides, ditches, rights-of-way, industrial sites and more clear of unsightly and troublesome weeds and vegetation.

The land is always going to present new challenges. A tool like HighNoon, with new site of action and more flexible options for combinations and application, can help you stay a step ahead of weeds while promoting desirable vegetation. With better control and convenience, it may be worth exploring HighNoon as an option in your program.

HighNoon™ herbicide advantages vs. other herbicides for weed and annual grass control in rangeland, pasture and non-crop areas:

New activity

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New active ingredient captures more species

More flexibility in application

Herbicide Flexibility icon

Use up to water’s edge, safe on grasses even at 4X labeled rate

Easier to handle and mix

Easier handling icon

Liquid formulation in gallon containers

Better activity

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More complete and faster kill, increased burndown, early activity

Promotes desirable vegetation

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Helps desirables out-compete invasives and weeds

Compatible with other herbicides to design your program

Compatability icon

Mix with:

  • Escort XP or Telar at the rates you need
  • Tordon® 22K herbicide at low rates when extra control is needed
  • Plateau and indaziflam to combat annual grasses and broadleaves

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1Corteva Agriscience. Field observations. Data on file.

Tordon 22K is a restricted use pesticide.

Under normal field conditions, HighNoon™ is non-volatile. HighNoon and Milestone have no grazing or haying restrictions for any class of livestock, including lactating dairy cows, horses (including lactating mares) and meat animals prior to slaughter. Label precautions do apply to forage treated with HighNoon and Milestone and to manure and urine from animals that have consumed treated forage.

When treating areas in and around roadside or utility rights-of-way that are or will be grazed, hayed or planted to forage, important label precautions apply regarding harvesting hay from treated sites, using manure from animals grazing on treated areas or rotating the treated area to sensitive crops. Label precautions apply to forage treated with Chaparral and Milestone and to manure from animals that have consumed treated forage within the last three days.

State restrictions on the sale and use of Milestone and Opensight apply. Consult the label before purchase or use for full details.

Chaparral, HighNoon and Milestone are not registered for sale or use in all states. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Always read and follow label directions.

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