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Wet Spring? Look to REGLONE for late season crop and weed control

field of wheat heads

Following the latest Australian Bureau of Meteorology modelling, growers are facing prospects of wetter than average spring conditions. This will increase the likelihood of inconsistent crop maturity, as well as in-crop weed pressure at harvest time, and strong demand for desiccation aids is anticipated to maximise yield and quality.

Responsibility to avoid herbicide residues in deliveries of cereal, pulse and oilseed grains rests on the shoulders of grain growers and their advisers, so it’s timely to review the non-selective herbicides that are registered for late season application.

The following chart summarises this well:

Non-selective herbicides that are registered for late season application

Paraquat formulations, such as GRAMOXONE® 360 PRO, can be used for spray topping annual ryegrass late in the season for chickpeas, lentils, lupins, vetch, faba beans and field peas, but not in wheat, barley, oats or canola. A seven day withholding period applies to pulse crops treated with GRAMOXONE 360 PRO.

Glyphosate is not registered for pre-harvest weed control in barley. However, some glyphosate products are registered for pre-harvest weed control in wheat, canola, chickpeas, lentils, faba beans and field peas. A 7-day harvest withholding period applies to both GRAMOXONE and pulse crops treated with glyphosate. A 5-day withholding period applies for canola and wheat crops treated with glyphosate.

REGLONE® is registered for use in all the above crops. It is registered for pre-harvest desiccation of canola and pulse crops and for pre-harvest general weed control in winter cereals. A harvest withholding period of zero to four days applies, depending on the crop. Always check the label for registered application rates and withholding periods.

Canola desiccation is a good option on lighter crops, where windrows may be blown about by strong winds. Ideal REGLONE spray timing in canola is when 70 per cent of the canola pods are yellow and the seeds are brown/bluish in colour and pliable.

For canola crops that are leaning over, the seeds on the upper side of the stem will mature ahead of those shaded from the sunlight. In this situation, spray REGLONE when all the seed in the exposed pods have turned reddish brown to dark brown.

For all crops, a wetting agent such as AGRAL® or BS 1000 should be added. Spray coverage is critical, so use application techniques that ensure good coverage and spray penetration as far into the canopy as possible. Higher water rates and larger spray droplet sizes will help, as too will application at dusk or early evening to maximise the limited amount of translocation that can occur.

While the primary purpose of using REGLONE is to desiccate the crop and improve harvestability, there will also be positive outcomes on weed seed set control (depending on the weed growth stage at time of application).

With strong demand anticipated, be sure to get in early to secure volumes of REGLONE for harvest desiccation this season.