Weed Resistance Seed Test

What herbicides to test? We test any herbicide(s), rates, mixtures, sequences.

On the last page of the sample registration there is a long list of herbicides to choose from for testing. If there are ANY other herbicides, other rates, other SEQUENCES, or MIXTURES eg. Paraquat + Boxer Gold etc. please enter this in the COMMENTS box during registration and we will include in the testing.

Please note that we use CLETHODIM EC240 & GLYPHOSATE 540. If you require another formulation let us know in the comments box

How long does it take? 8-12 Weeks

The Seed-test usually takes 8 to 12 weeks assuming seeds are viable and are not highly dormant. Send lots of seed where possible, eg an A4 envelope full of seed heads. This is usually 5-10 minutes longer in the paddock. Collecting less seed can increase the testing time and delay the reporting of results.

Seed Test

Seed samples can be collected from the paddock prior to harvest. Even after harvest, seed heads can usually be found. For wild oats, brome, barley grass etc. that shed readily, seeds are usually found on the soil surface. Contaminated grain or header screenings can also be sent. We can separate out the weed seeds.

Sampling will depend on the resistance situation of each paddock.

If resistance is widespread, then collect seeds following a ‘W’ shaped area every 10-20m across the suspected paddock or problem area.

Alternatively, you may collect seeds from suspect areas.

Do not bias the samples by collecting seeds from a small number of plants but aim to collect a similar number of seeds from each plant.

If the seeds are not completely dry they should be sent in paper envelopes to avoid rotting in plastic packaging.

Herbicide choice

During registration you can choose which herbicides to test. If you are unsure, register the sample. Contact us if you wish to discuss herbicide options.

How many seeds?

To complete a resistance seed test, fill an A4 envelope full of ryegrass or other grass seed heads or wild radish. The pre-emergence herbicide bundles for ryegrass require a lot of seed.

Suitable seed volume for testing

How long will it take?

Seed tests take about 12 weeks once dormancy has started to break. Pre-emergence herbicide testing of ryegrass begins in March. Post-em herbicide testing begins in January. Every effort will be made to get results back to the sender by March-May. We test seeds based on when they arrive so don’t delay in sending us the seeds.