The most widely used material is diquat . A non-ionic surfactant can be added ( but before spraying consult the processor in the case of crops grown for human consumption ).

Moisture content of combining peas seed should have fallen to 40-45 %. At this stage the seed is mature , and the crop yellow , lowest pods nearly brown and at the dry , ‘ parchment ’ stage , those higher up being yellow . The seed within the pods should easily detach from their stalks and feel rubbery . If the desiccant is used too early , yields may be reduced and quality affected .

Apply when 90 % of field bean pods are dry and black and most of the seed is dry . At this stage , most of the leaves have senesced and fallen but the stems are still green . The contact action is fast , and harvesting can be carried out 4-7 days later .

Glyphosate is not a true desiccant but can be used as a pre-harvest treatment to control perennial weeds . It must not be used on crops destined for seed . Combining pea harvest

Care should be taken in harvesting peas , and if destined for the packet trade , chip shop or export , value is reduced if pea seed is ‘ bleached ’ by the sun . Quality can be affected by wet weather at harvest causing staining in a lodged crop . If moisture content is low (~ 12 %, or if they are over-dried ), the crop may be unsuitable for human consumption , the percentage of ' non-soakers ' increases and the seed may split and crack . Peas for micronising for pet food must also have a good blue / green colour . Yield is lost if peas are left too long in the field and shelling out and pod shatter occurs . Tips for combining :

> Combine in the opposite direction or at an angle to the

direction of lodging . > Lifting fingers are essential at least one every fourth position .

> Adjustments may be necessary to lower the cutter bar close to the soil surface .

> The reel is positioned slightly forward of the cutter bar and speed adjusted to lift the crop onto it .

> Combine settings - peas are easy to thresh so drum speed should be set to a low setting as per manufacturers recommendation .

> The concave should be opened up to reduce time the crop is in contact with the drum . Use high fan setting .

> The appropriate screen size for peas must be used .

> Quality is reduced by soil contamination . Do not combine when there is surface moisture on the haulm , or when the soil is wet , and make sure the combine is clean .

Peas can be combined when moisture content of the mature seed is 18 % MC , and higher quality seed and human consumption is often achieved by early combining at 18-20 % MC , followed by careful drying . This avoids damage to the seed coat , and a higher percentage of nonsoakers . Do not leave peas in the field until 12 % MC .

If peas are required for animal feed , they can be combined at moisture content lower than 18 % and drying costs are reduced . At low moistures the seed may split , but split peas are still acceptable for animal feed . However , harvesting at such low moisture content may well significantly reduce the recoverable yield due to pod shatter and shelling out .

Where possible , crops should be direct combined without preharvest desiccation , only practical in a dry harvest , in a weed-free crop that is dying back evenly . Field bean harvest

Beans are often perceived as being able to withstand harvest delays long after other crops such as cereals have been harvested . Other operations , including seedbed preparations and oilseed rape sowing , can often take priority over bean harvest .

However , once beans are ready to harvest the quality will begin to deteriorate . If pods split and beans are exposed to light this will cause the seed coat to darken and increase the amount of crop loss during harvesting . When mature , cycles of wet and dry weather increase the chances of staining if they are not harvested . Quality is key to achieve the human

consumption premium . Drying and storage for combining peas and field beans

The quality standard for peas and beans is usually 14 % moisture content ( MC ) with 2 % impurities , or a combination of the two that should not exceed 16 %. Drying can be more difficult with peas and beans than with cereals due to seed size , and while damaged produce is acceptable for compounding , mouldy produce is not . Peas and beans should not be over-dried and at higher temperatures texture may be affected and peas may split .

The large size of bean seeds makes drying difficult as they have a low resistance to air flow . It takes time to move moisture from the inside to the outside hence slow , gentle drying with ambient air is best .

There are several types of dryer that may be used for peas and beans , but those operating at low temperatures are safer .

* Floor-ventilated bins are easy and relatively safe to operate . When the initial moisture content is high , the transfer of the produce from bin to bin and the use of warmed air together with adequate ventilation may be necessary to avoid mould developing in the upper layers .

* Radially-ventilated bins allow faster drying than floor-ventilated bins , but care must be taken not to overheat peas and beans .

* On-floor drying using ambient or warmed air can be used , and provided there is

sufficient volume of air and adequate ventilation , peas of relatively high moisture content can be dried using this method . Care must be taken not to load beans too deep if moisture content is high and if lateral ducts are spaced wider than 1m .

* Continuous flow driers designed to work on a short period / high temperature basis need more careful operation than other systems for peas . Use of continuous flow driers should be avoided where quality is important since they may cause cracking .

For safe storage , the maximum moisture content of peas depends upon the method and the length of time they are to be stored . Peas may be safely stored for up to 4 weeks at 17 % MC , but if they are to be stored until the following spring , the moisture content should not be above 15 %. If the peas are in bulk with forced ventilation or frequently moved , the moisture content can be 1 % higher .

Storage in dark areas is recommended for beans destined for the human consumption market to delay the development of tannins which cause beans to discolour . Beans must be dried down to 14 % MC for long-term storage in bulk - this is important since beans are often stored for some time before they are sold .