Lentils have emerged as a key component of the intensive cropping operations of the Edmonds-Wilson family at Coonalpyn in SA's upper South-East.
John Edmonds-Wilson and parents Don and Helen crop about 900 hectares of cereals, pulses and canola annually in this 450 mm rainfall area.
They first tried lentils in the 1980s but gave them away because of indifferent yields and difficulties with weed control, returning to the pulse in 1996 with the advent of improved varieties, more herbicide options and good gross margins relative to other cropping enterprises.
Three good reasons to grow lentils
"There were three other reasons, as well," John Edmonds-Wilson explained. "We have trouble with snails contaminating grain and clogging up headers, and peas are about the same size as the snails, making them difficult to grade out. With the smaller seed size of lentils, however, we can float the snails out the back of the header.
"By sowing lentils we can also spread out the time of sowing — beans, canola and malting barley have to go in early but lentils go in later, after wheat. Another reason for sowing lentils is that they provide a good stubble coverage after harvest and minimise the risk of wind erosion through summer and autumn."
In 1999 the family reaped about 120 hectares of lentils, mainly Northfield but also some Aldinga. Mr Edmonds-Wilson says that they have found that Northfield's yields are satisfactory, but it has the added advantage of seed resistance to Ascochyta blight and it tends to lodge less than Aldinga.
He was a member of the local Lentil Check (TOPCROP-linked) group formed in the area in 1997 when individual crops were monitored closely and group members' crops inspected to facilitate information exchange.
"No-one has a mortgage on good ideas, so group inspections were helpful," he said. "Overall the Lentil Check program was extremely beneficial, showing us, among other things, what we should be looking for in our lentil crops at different times of the year."
Mr Edmonds-Wilson says he has learned that to maximise lentil yields, good paddock preparation and weed control are essential, along with in-crop vigilance and remedial action against pests.
The Edmonds-Wilson lentil 'year' can be summarised as follows.
- Cereal stubbles are slashed and the paddock cultivated generally twice for weed control before sowing lentils. Germination following a heavy cereal stubble has not been a problem.
- Glyphosate is used as a knockdown before seeding and the lentil seed is tested for the presence or otherwise of seed-borne diseases. If test results show high levels of infections, clean seed is sourced.
- The seeding rate has settled at about 50 kg/ha with Treflan incorporated at seeding along with 100 kg of MAP containing 1 per cent zinc. Paddocks are rolled after seeding to lessen the chance of stones being a problem at harvest.
- The herbicide Lexone at 250 g/ha is applied post-sowing pre-emergence for further control of broad-leafed weeds including mustard and then a grass herbicide such as Fusion or Select is used to control weeds including ryegrass, brome and barley grass and volunteer cereals.
- During August, snails are controlled using metaldehyde baits at about 5 kg/ha and a foliar spray of manganese sulphate is used as an insurance against manganese deficiency.
- Aphids which can transmit viruses are sprayed as soon as they are seen, along with heliothis — the latter when pods start to form on the lentil plants.
- As part of the overall grass-weed control strategy and to pick up any 'escapes' from earlier sprays, the lentils are crop-topped with Gramoxone at 500-600 mL/ha.
"Timing of the crop-topping has to be right," Mr Edmonds-Wilson said. "The recommended time is when lentil seeds are well-formed within the pods and crop is starting to go off — if you go too early, yields can be knocked around."
The Northfield lentils were yielding 1.8 t/ha when Ground Cover called at the Edmonds-Wilson property in mid-November. This compared favourably with 1.67 t/ha in 1997 and a frost-affected 1.6 t/ha in 1998.
The family is pleased with the 1999 yield, considering rainfall was well down on the average, only about 260 mm falling in the growing season.
Depending on final yields and prices, Mr Edmonds-Wilson expects the lentils to produce a gross margin of $500-$600/ha, putting that pulse financially in front of the lupins and beans, and on par with canola.
"We anticipate increasing the area to lentils in the year 2000," he said, "although we would have to reconsider if the price dropped to, say, $300/t from the present $446/t on-farm."