After harvest attention switches to managing and selling the stored crop growers have worked so hard to produce over the year.

An essential part of managing and selling grain is knowing the quality which relies on accurate sampling. This helps avoid deductions as growers know if each load passes or fails the required specifications.

“For growers, knowing the quality of your grain is essential so that you can store it then sell it effectively,” says HGCA chairman, Jonathan Tipples. “This means you can get the best return for your work.”

But last year’s low specific weights and resulting deductions together with discrepancies between on-farm sample sand samples taken at the intake has put sampling accuracy back under the spotlight.

See also: How to prepare grain stores for harvest

NFU’s chief crop advisor Guy Gagen, says improving on-farm sampling can really pay dividends, giving growers a better understanding of what is in their store and giving confidence in challenging any claims against them.

“It helps avoid any unexpected results and limit the resulting claims by resolving any apparent discrepancies early on,” he says.

Four key stages for sampling grain

1. Know the harvested quality so that growers can dry and cool the grain as necessary and identify potential buyers.
2. Protect the harvested quality.  Stored well, grain quality should not deteriorate, but store managers need to be on the look-out for any early signs of spoilage or infestation.
3. When grain leaves the farm, it is important to get a sample of what is loaded onto the lorry. This provides a record of what has been sold and can show that the grain meets specifications. In addition, farm assurance schemes often require this type of sample to be retained to ensure traceability in the supply chain.
4. The final stage for sampling is at commercial intake where buyers use automated equipment to take samples from lorries as they come in. These samples are used to confirm that the grain meets the specification and also to inform decisions about further processing according to the guide.

 Top tips on the sampling process

1. Getting a representative sample

A sampling programme involves taking a number of small incremental samples from across different points of the heap to give more representative picture of the grain.

These incremental samples need to be thoroughly mixed together to form an aggregate sample. For a 30t lorry-load of grain, take at least 10 samples of 200g, as the grain is loaded. This will provide a 2kg aggregate sample.

2. When and how to sample

Best practice is to take and retain samples from each lorry load before it leaves the farm. This gives a record of what is on the lorry and greatly reduces the possibility of disagreements between grower and buyer over the delivery quality.

There are a number of different methods and points where these samples can be taken. One option is simply taking small samples by hand from each loading bucket before being tipped into the lorry. However, this really requires a second person.

Automatic bucket samplers offer a safe and convenient way to sample. The sampler is permanently fixed on the back of the grain bucker and is a robust and simple unit device that normally collect around 0.8kg and 2kg of grain until full.

They extract a small amount of grain from each bucketful during the process of loading a lorry. These individual bucket samples are mixed in the sampler to form an aggregate sample, so all the operator has to do is empty the sampler after each lorry has been loaded and bag them up.

If the grain is loaded using a conveying system, locate a safe place to draw off samples close to the final loading location.

Samples may also be taken from on-floor stored grain using a conventional grain spear. Growers are advised to collect at least ten 200g samples which are then combined together to make the 2kg aggregate.

3. Retaining back up samples

Every sample taken from each lorry load should be split in half to produce two 1kg samples. One is sent for analysis while the other is kept on farm as a back-up. Careful labelling is also needed in order to keep a track of every sample taken.

This also helps with a number of farm assurance schemes, which require this sample to be available.

All grain samples should be stored in airtight containers for example, polythene bags or plastic boxes, in a cool, dry place safe from rodent attack.

Each should be labelled with basic information, including: Farm name, store name or number, bin number, variety, date, time, vehicle registration and trailer number.