Wheat (1) - Part 3

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tified it, and reported on the seriousness of the outbreak. Efforts were at once made to cope with it and get the wheat shipped away. It was practically all cleared out of the sheds at the earliest possible moment, but, unfortunately, the insect, which is a good flier, got across to the North Wharf, where last year we discovered it in two or three large stacks. I again drew attention to the seriousness of this pest. The weevil requires moisture, and so we hope to beat it by storing our grain at inland depots, away from the moisture of the coast; but with this beetle moisture does not enter into consideration. It rather likes dry conditions and so we may have in it a very serious field pest, if it succeeds in getting out into the wheat districts. The eggs of this insect are laid not in but upon the grain, or upon the grass surrounding the grain. The larva is legged and can move about. This larva consumes whole grain, and will live in flour, bran, or pollard. Thus its operations may be very much more serious than those of the weevil. The egg stage occupies from five to 10 days in the summer and the beetle can lay from 400 to 500 eggs. The larva will pupate inside the grain, or amongst the frass, and that period lasts from 12 to 14 days. The pupa stage is from eight to 10 days, the total life cycle being from 25 to 34 days. The imago may live many months. In the grain moth we have an insect which operates in exactly the same way as the weevil, with the difference that we have in the one case a beetle and in the other a moth. This moth is found primarily in the Victoria district, where it has done considerable damage. It is also found in most of the stacks at Fremantle. The moth lays her eggs generally upon the groove in the grain of wheat, and the egg will hatch in from four to 16 days. She is capable of laying 100 eggs. The larva, like the grain weevil, lives inside the grain but is not legless. It is an ordinary six-legged caterpillar, with a number of sucker legs, and is capable of moving about. Before pupating, this caterpillar will cut a small circular hole in the grain, sealing it down with fine silk. This is done against the time the moth is ready to emerge. The larval period is from 15 to 40 days. The pupa period is anything from 10 to 60 days, and the moth lives from 16 to 18 days, and we have a total life cycle from egg to adult of from 30 to 116 days. The longer period representing the cooler seasons of the year. These are the three main insects affecting our stored grain.

5388. What do you call this insect in this sample of wheat?

5389. What do you call the weevil in this particular bag?—That is a rice weevil. There may be a few grain weevil mixed up with them. They are so much alike that when they are covered with pollard or dust it is difficult to determine which is which.

5390. This is Geraldton wheat?—Then I should say 98 per cent. of these are rice weevils. We can see here the typical work that the weevil does. I think the main thing to do at present is to keep our new sites clean.

5391. What about this other sample of f.a.q. wheat, which was taken from the 1915-16 harvest and has been stored on a shelf?—There is no evidence of weevil here at present. This sample proves that the weevil is not spontaneous. Nine people out of ten would say that it would be impossible to put this wheat into a bag and not have weevil in it. I could show the Commission 40 samples of both soft and hard wheat like this taken from the field.

5392. By Mr. BROWN: Has there been any difference noticeable between the samples kept in bottles and those kept in bags?—No. I put some in bags and some in stoppered bottles so that it might not be said that the grain in the bottles had not sufficient moisture in it to enable the weevil to develop, and in order that I might have grain under both conditions. The whole trouble seems to start from the stripping of the wheat. When the average farmer buys a bale of bags he will throw it into his barn which, in almost every case, is infested with weevil. During the winter time the weevils will hybernate in the bags. The bags are then taken out into the fields with the weevil in them. Perhaps the weevils have also crawled into the stripper, which may be kept in the barn. The wheat is drawn clean from the car by the stripper, and the contamination begins either from the stripper or the bags or from both sources. If we could get people to start from the beginning and see that their bags were treated, and that their strippers were cleaned, before being taken into the field, and that the sites upon which the bags of wheat were stacked were also clean, it should be possible for the farmer to send his wheat away entirely free of weevil. All bags ought to be treated with a 5 per cent. solution of salt in boiling water. The bags should then be thoroughly dried before being sent out to the field. This would entirely kill all weevil. If the precautions which I have enumerated were taken, then any contamination of wheat which took place would take place after it had left the farm. The use of such a solution would not only kill the weevil, but would act as a repellent. In no other way would it be possible to guarantee that the farmer was not to blame in the first place for starting the weevil in his wheat. Should contamination occur after the wheat leaves the farm, provided that these precautions have been taken, it would be due either to the dirty trucks into which the wheat had been put or to dirty sidings at which the wheat might subsequently be stacked. The fact that wheat may get wet will not bring weevil, but the weevil will seize upon such conditions as being suitable to their requirements.

5393. Have you ever known of the growing crop being infested by weevil prior to stripping?—No, not in this State.

5394. By Hon. J. F. ALLEN: The rice weevil can only be carried from place to place in the beetle stage, unless it is already in the grain?—It may be carried in the larvae stage, but can always travel when in the beetle stage. It is necessary for the beetle to have the grain on which to lay its eggs.

5395. If the insect is being introduced here through the medium of bags, it can only come in the beetle stage?—I am not speaking of the introduction of the beetle into this State. Perhaps these bags are free of weevil upon arrival, but when the farmer dumps them into a weevil-infested barn the weevils will crawl into the bags.

5396. They may enter the bales in the ship or when they are in the trucks?—Certainly. If weevil is in those places in which the bags are stored, the bags will certainly become infested. It is simply a matter of the weevil accommodating itself.

5397. Even if the farmer has a clean farm he should still treat his bags?—All bags should be treated.

5398. Have you any suggestion to make as to what the Railway Department should do with their trucks?—One requires to know a good deal about railway management to be able to make a suggestion. This should really come from the Railway Department. No proper solution of the difficulty has ever been brought forward. That was the great difficulty in the Eastern States, and also as to how to ear-mark trucks so that they would not be standing idle when they were required. The amount of rolling stock will not permit of trucks being ear-marked in this way. We tried various solutions of tar oil. This leaves a considerable odour in the trucks. It will kill the weevil, but as new wheat is very sensitive and readily picks up odours, it is possible that the flour into which it is made will be flavoured. Similarly, other goods that are equally sensitive may afterwards be put into those trucks and also become tainted. We also tried to kill the weevil in the trucks by the steaming process, but this was not successful. It is difficult to get the hot steam into the crevices of the trucks, because exposure to the air cools it off before it has time to do any good. The weevil is extremely hard to kill, because it is coated with a substance which protects it from things which would readily kill other forms of insect life. The carriage of wheat in railway trucks is a great problem. If this trouble could be overcome, we should probably be able to keep our new season's wheat clean. To overcome this difficulty is easier said than done.

5399. In your opinion, that is the crux of the whole problem?—Yes, provided the farmer also does his share in the method I have suggested.

5400. By Mr. BROWN: Have you any knowledge of wheat stored in silos?—No. I do not think any man in Australia has the requisite practical experience. My own opinion is that this is the only method of coping with the weevil.