SODIUM CHLORATE.

Press, Volume LXVI, Issue 19818, 4 January 1930, Page 8

SODIUM CHLORATE.

WEED-KILLING PROPERTIES. An interesting feature of the inspection hv farmers last month of Lincoln College farm was the experiment being carried out by Dr. Hilgendorf in the direction of the destruction of California thistle t>y the application of sodium chlorate. The experiment*appeared to be entirely successful. It is interesting, in view of the College effort to reproduce an article from ''Hoard a Dairvman," written by a farmer on the results attending the experiment in eradicating bindweed. Bindweed is better known to us as convolvulous, and is a particular > vicious weed in many other countries., liie writer states: Interest in the use of sodium chlorate in the eradication of field bindweed la on the increase. As yet, it cannot be said that this method of eradication is so fully developed &o as to bo effective. However, investigational work is being carried out in several States and already the trials have been such as to hold the belief that the chemical has excellent possibilities. The writer was in attendance at ttie summer meetings of the Corn Belt section of the American Society of Agronomy which were held at the Kansas Agricultural College at Manhattan. At this meeting the subject was discussed by J. W. Zahnley of the Soils and Crops Department of .the Kansas institution. Professor Zahnley s talk was of especial interest because it was at Manhattan that the first work in the trial of sodium chlorate for weed eradication was carried on. Unsuccessful Salt Experiments. The first work along eradication lines in Kansas dealt with the use of salt and the summer fallowing of the land. The experiments with salt showed that only effective amounts were around 20 tons per acre at a cost of around 21/per ton. Following the use of such large amounts of salt, the land was virtually useless for an indefinite period. It was in 1925 that the Chemistry Department of the college started some erperiinentnl work with various chemicals. Of the chemicals used, sodium chlorate seemed to be the only one showing real promise. In the first trials with scdium chlorate at the Kansas Station, three applications wore made starting with August and ending before frost. The next spring there were no bindweeds showing up. Experiments were carried on to determine what effect, if any. the eedium chlorate had upon the yield of grain. In trials made, it was found that plots treated at the rate of 3001b per acre yielded 27 bushels per acre, while those plots receiving 6001b per acre yielded four bushels less. The extensive experiments of Professor Zahnley and his associates indicate that one pound of sodium chlorate to the gallon of water and applied at the rate of 100 gallons of the liquid per acre, is about the right amount The bindweed should be saturated. Application of the sodium chlorate when the leaves of the bindweed are in full bloom or two or three weejes after they come into full bloom, is recommended as the best time for the first spray. The second may be given four to six weeks later. The third application, if needed, may be given eight to ten weeks after the first application, depending of course upon the weather conditions and the growth of the plants. Professor Zahnley stated that if the growth of the bindweed is especially vigorous, it may be well to give four applications of the sodinm chlorate. The results secured in Kansas indicat#

that 90 per cent, of the plants may be , destroyed in a single season. | Handling the ChemicaL j The firo hazard has been spoken of ; in connexion with the use of sodium j chlorate. In all the experimental work ; at the Kansas Station there has been ; no serious fire. Fires may be avoided j by wearing rubber boots antl by wash- , iiig out all clothing which becomes) moistened with the solution. The chemi- j cal should be* stored in metal containers ; in a dry, clean room, away from hay, j straw, sulphur, or other materials which j may cause trouble from fires. ork has . been in progress at the Kansas Station j to see if some other material may ret ■ be combined with sodium chlorate to I reduce the fire hazard and preliminary | work indicates that calcium chloride in I certain amounts will render the material j non-inflammable. J The Agronomy Department of the j Nebraska College of Agriculture has j been, for the past two years, carrying j out field denionstrations with sodium . chlorate. This department makes the statement that the use of sodium chlorate seems best adapted to small patches of bindweed and other noxious weeds. Where tho infested area is large and the plants are widely scattered, they do not regard the sodium chlorate method as a particularly practical method. The Nebraska agronomists place the cost of three applications of the sodium chlorate spray at £7 10s per acre. From the foregoing it would appear that expense would bo a barrier to the use of the chemical in destroying twitch, but as the Lincoln College operations indicate it should be ail economic proposition for weeds that flourish in patches, such as Californian thistle A "Field Day" for farmers will be held at the Ashburton experimental farm next Tuesday, January 7th, the object being to enable farmers to inspect tho potato trials being conducted in connexion with certification and the wheat selections growing on the farm. Gould's motor buses will leave the Post Office, Ashburton, at 10.30 a.m. to convey farmers out to the farm, where short addresses will be given and the various phases of the work in connexion with the plots explained by Air J. W. Hadfield, agronomist, plant research station, and other officers. Light refreshments will be served. Fotato growers, particularly those who liavo entered their lines of potatoes under the certification scheme and samples seed are on trial on the farm, will find much to interest them in comparing their varieties with others grown ur.der similar conditions. The Royal Agricultural Societv of England made a profit of £ 87!>5 on its last show Harrognto.