MARTON EXPERIMENTAL AREA.

New Zealand Journal of Agriculture, Volume XIII, Issue 4, 20 October 1916, Page 276

MARTON EXPERIMENTAL AREA.

The following notes, dealing with the chon moellier crop, subsoiling, &c., are furnished by Mr. G. de S. Baylis, Fields Supervisor, in continuation of his report, published in the July issue of the Journal, on operations at the Marton expedmental area :

It may be restated in the first place that the experiments at present being carried on at Marton are a rotation course for the improvement of the soil, consisting of clover or similar crop for two years, or Italian rye-grass and clover followed by wheat, which in turn is followed by a root crop, or rape, kale, chou moellier, &c., then oats, and again Italian rye and cow-grass, or permanent pasture if it is desired to throw the land out of cultivation. When possible it is also intended to disk oat and other stubbles after harvest, and, if the season permits, drill in a few pounds of Italian rye, or suchlike, to be used as green fodder during the winter, and plough under in the early spring, thus affording the land a certain amount of -supply and also dung from the stock consuming the green feed. Disking directly after harvest also assists to clean the land, and at the same time to promote the germination of weed and other seeds shed thereon, which plants in their turn are destroyed when the catch-crop is ploughed under.

The notes taken with regard to chou moellier during the past season are to the effect that this crop suffers just as severely from the attacks of turnip-fly, during the early stages of growth, as do swedes, &c. When fully grown, however, while an adjoining rape crop was consumed by cabbage-moth and aphis, leaving nothing but the bare stump, just as if it had been hard grazed by sheep, the chou moellier was still affording an abundance of leaf.

The first sowing of chou moellier was entirely taken by fly, and a second sowing was necessary. Gaps were also made by the fly in the second sowing. As the early hay crops were ready for cutting before the chou moellier plants were ready to transplant, labour for transplanting was not available ; hence, seeing that uniform conditions did not exist, the taking of grazing-records for comparative purposes was not advisable. It was also not advisable to incur the expense of separately fencing and recording the chou moellier plots.

Italian rye-grass being sown in all oat and wheat stubble and other •plots, the feeding-off of the chou. moellier was deferred until such time as the Italian rye should be fit for feeding, which was not until the end of May. During the interval the leaves of the chou moellier were •consumed bare to the very ribs by the blight. Thus a first feeding was lost. When the rains came the crop rapidly recovered, but the lambs (tegs) neglected to a large extent the old growth which had suffered from blight, treading this under while they consumed the later and fresher growths. The results are as may be imagined —that whereas the average grazing-capacity of 1 acre of chou moellier last ■season was 100 lambs for twenty-two days, this season the average would probably be 100 lambs for rather less than ten days. This affords a positive proof, if any were necessary, that when a op is badly attacked by blight considerable monetary loss is likely to ensue unless the crop is fed off at once. There does not appear to be anything .gained by restraining from feeding off when blight attacks the crop, as the stock largely destroy any of the older growth which may to a certain extent have escaped the blight, while seeking the fresher growths which are more palatable. Neither is additional vigour retained by the plant.

Chou moellier has now been used at Marton for two consecutive seasons, and the lambs have done well on it. The practice is to sow about i lb. of good germinating seed in drills 28 in. apart, and horsehoe as soon as the plants are sufficiently in evidence. This clears the weeds from between the rows. Later, for a second cultivation, the double mouldboard plough is run between the rows, and, while moving the intersurface, this covers up most of the small weeds growing between the plants in the rows, thus avoiding much hand-work. Wet weather in August retarded ploughing operations. One of the cffiver plots in each of the sections was, however, turned over about the end of that month.

Since the land has been properly drained with the mole-plough it is noticeable that even after very heavy rains, such as have recently occurred, the water gets away very quickly, and the land soon becomes sufficiently dry for working operations. Italian rye made good growth

all the winter and carried a fair number of stock. This I largely attribute to drainage.

On the acre which was subsoiled the clay beneath the top-soil isstill loose and friable to a depth of 3 in. or 4 in. This plot yielded 84 cwt. 2 qr. 14 lb. pure clover hay per acre. The non-subsoiled plot yielded 55 cwt. 41b. per acre. Both plots have also afforded a good, deal of grazing. On the subsoiled plot the clover-plants have stout roots and heavy crowns, the roots being dragged out by the plough and broken off at an average distance of 12 in. to 14 in. from the crown. On the non-subsoiled plot the roots are much thinner, and the crowns not as heavy, nor the' plants as well developed. They break on an average, say, of 9 in. to 10 in. from the crown. This gives a very good idea of the increased depth at which the clover crop is feeding on the subsoiled plot, and is an indication that the method adopted is realizing its object—namely, gradually increasing the depth, of cultivable soil on the Marton area.

. . The subsoiling at Marton was done in 1914 by a P. and D. Duncan subsoil attachment to an ordinary double-furrow lever plough. One' mouldboard was removed and the subsoiler attached, ploughing and subsoiling thus being accomplished at the same time. On the stiff clay lands at Marton , a five- or six-horse team is advisable if deep ploughing and deep subsoiling are to be undertaken at the same time. At the experimental area the land was ploughed to a depth of about 6 in. and subsoiled to a further 4 in. or 5 in. With the attachment used it was quite possible to plough both furrows and subsoil sameat the one operation. If it is only intended just to loosen the surfaceof the subsoil it is quite possible to do so with the ordinary team, but when any considerable depth is undertaken a stronger team becomes necessary. .

The cost of ploughing and subsoiling land similar to the Marton area, contrasted with the cost of ploughing in the usual way with a double-furrow and a four-horse team, may be stated as follows : If a depth of, say, 6 in. or 7 in. is ploughed, and a further 3 in. to 4 in. subsoiled, five or six horses will be required, according to quality, instead of four, and one furrow will be ploughed while the other is being subsoiled, thus taking as long to plough the acre as if you were using a single-furrow plough.

As to how often it may be necessary to subsoil on the class of country mentioned, I am not able to state more at present than that subsoiling at Marton was undertaken two years ago, and that, as indicated, the clover crop of the past season proves the fact that not only is the subsoil still free to the original depth stirred, but that the clover-roots are now feeding therein. This shows that such cultivated area of the subsoil is now providing plant-food, and that therefore the nature and condition of the subsoil has been changed from what it originally, was namely, inert matter practically of little value to the plant.

The chou moellier plots were disked after the stock were removed,, and subsequently ploughed. On the green-manured sections there still remains abundant evidence of the green oats which were ploughed under in August, 1915. Much of this material should now be in condition to afford fertility to the soil during the present season.