LECTURE ON AGRICULTURAL CHEMISTRY.

Hawke's Bay Herald, Volume XXI, Issue 5416, 24 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.C., 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 hast 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 eggswere united in the form of a chain, but in a subsequent stage they were separated from ieach other. When in the last stage of its metamorphosis the fungus was spread over the length and breadth of th 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._ a *. w ~_TJfc_e._ 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,, aad.it had proved efficacious.'"* lii ''America the usual system of steeping copsist^d in throwing the seed into a solution of common salt (of sufficient strength to float an egg), 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 1-I2th 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 nsed for a sack of wheat should be dissolved iii sufficient water to thoroughly moisten the seed. In a lecture to be given in Victoria, the lecturer will recommend for trial a new ateep for wheat which he believes will replace ali 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. t . 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 reconuherid early and thin sowing. If land "'was'?, too thickly Bown the plants would!.' 'come up too close together, and, in struggiihg'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 likely to take disease than , a- strong one, and the same rule holds 'good 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, iMr MacTvor 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.