LECTURE ON AGRICULTURAL CHEMISTRY.

New Zealand Times, Volume XXXIV, Issue 5684, 18 June 1879, Page 3

LECTURE ON AGRICULTURAL CHEMISTRY.

A lecture was recently delivered in Tasmania by Mr. R. W. Emerson Maclvor,' who was brought to the Australian colonies by the Hon. W. J. T. Clarke, M.L.0., Victoria;; for the purpose of imparting a scientific knowledge of farming and agricultural chemistry to his tenants. The subject of the lecture was rust in wheat. The disease (said the lecturer) originated in undrained land, and attacked the wheat about (often before) the time of flowering. The rust fungus, examined under the microscope, presented the appearance of a mass of eggs, each of which possessed a rootlet projecting from the end. In the early stage of development the eggs were united in the form of a chain, but in a subsequent stage they were separated from each other. When in the last stage of its metamorphosis the fungus waaspread over the length and breadth of the land by the winds, and settled in hedges and other vegetation, from which, in the following season, it found its way to the. wheat crops in the neighborhood. Rust and smut had in a great measure disappeared from Scotland and other countries where drainage 'had been generally introduced. Hence draining was a preventative. The process of steeping or “ pickling ” wheat seed arose through practical and scientific men having found that “ rust ” adhered to the grain, and that unless some means were adopted to destroy it the disease would spread to the crop. One of the oldest steeps was putrid urine, and it had proved efficacious. In America the usual.system of steeping consisted in throwing the seed into a solution of common salt (of sufficient strength to float an e fr<r ), and after the light grains and seeds of weeds had been “ skimmed ” from the surface of the liquid, the seed was taken out and mixed with l-12ih of its weight of slacked lime. He (the lecturer) had found from his researches that contrary to the general impression the ..salt did not kill the rust, but that it was the lime used for drying the seed that accomplished this end. The usual “steep” or “pickle,” for wheat seed was Milestone (sulphate of-.copper). The quantity of this material 'used for a sack of wheat should be dissolved in sufficient water to thoroughly moisten the seed. In a lecture, to be given in Victoria, the lecturer will recommend for trial a new steep fur wheat which he believes will replace all other now in use. In addition to these preventatives of rust the farmer should use no other than hard straw wheat, as these were more capable of resisting the disease than such as had soft straw. 'But, as all varieties of wheat were liable, during certain seasons, and especially in rich soils to a “flaggy” or too luxuriant growth, he would recommend early and thin sowing. If land was too thickly sown the plants would come up too close together, and, in struggling for the same food, would act injuriously upon each other, the more vigorous starving the weakly and at the same time injuring his own strength. A weak animal is more liable to take disease than a strong one, and this same rule holds goods with plants. Weaken the growth of wheat, and the straw,, will be the more liable to the attack of, rust. If land is too rank for wheat a dressing of two or three cwt. of salt per acre will remove any chance of “flaggy” straw, and at the same time insure a yield of excellent grain. ;In concluding his remarks, Mr. Maclvor said science could not give other advice than that which he had endeavored to give, and so the farmer, to avoid losses, would do well to follow it out to the best of his ability.