Monolith – Product Overview

Monolith is a new post-emergence herbicide formulated to tackle the increased range of cereal grass weeds in Ireland. It partners two actives with exceptional grass-weed activity – mesosulfuron and propoxycarbazone. This combination means Monolith has the power to control a wide spectrum of grass-weeds including sterile brome, meadow grass and black grass.

When should I use Monolith?

Monolith is the final step of a grass weed control programme following on from cultural controls and a robust pre-em. Monolith can be used in spring from the 1st February in the year of harvest, when the crop has reached the 1-tiller stage until 2nd node detectable (GS21–32).

Uptake is mainly through the shoots so there needs to be some active growth for the herbicide to take effect; care is needed for applications in February when conditions may be cold. Weather conditions at application are very important; apply to a dry leaf with sufficient drying time before dew forms.

Like other Bayer post-ems, applying Monolith when the target weed is small increases the overall level of control but conditions need to be right. Applying in cold or wet conditions is not advisable even if the plant is small because the active substances will not be taken in effectively.

How should I apply Monolith?

It is often said that the control from herbicides is 50% chemistry and 50% application and Monolith is no exception. The aim is to land the herbicide on the target leaf so it settles, dries and is taken in by the plant. To do this a fine spray, possibly fine-medium is required. Generally, the flat fan type nozzle produces a finer spray than the air inclusion nozzle.

Forward speeds should be no more than 12 km/h and make sure the sprayer boom remains stable to get a consistent application. Water volumes of 200 L/ha are suitable for Monolith.

All applications should include 1 L/ha of the adjuvant biopower.

Will it control brome and other grass-weeds?

Monolith is highly effective against bromes. In five independent trials from 2016-17 Monolith gave class-leading control of brome populations. Growers should always incorporate resistance management by including varying modes of action and at least two cultural control methods.

Monolith easily matches the performance of Pacifica Plus against rye-grass and meadow-grass if these are an issue on your farm.

Will the strong activity affect my crops this year or next season?

It is right to consider crop effects on any herbicides with strong grass-weed activity like Monolith. In season, the level of crop safety is equivalent to Pacifica Plus i.e. safe if the label guidance is followed. For following crops, winter oilseed rape requires deep cultivation if Monolith is used.

What can I tank mix with Monolith?

Simple tank mixes with just Monolith + biopower and a residual partner if necessary give the best results but workloads mean that is not always possible. Applications with T0 or T1 is the main concern in early spring so pay attention to the fact that mixes with tebuconazole and chlorothalonil are not supported due to crop safety and antagonism respectively. Consult the tank mix guidance sheet for more details.

Monolith Product Summary

Active substances
A water dispersible granule formulation containing 45 g/kg mesosulfuron-methyl and 67.5 g/kg propoxycarbazone-sodium

Winter wheat, winter durum wheat, winter triticale, winter rye, winter spelt.

Pack Size 2kg