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Work by the Dominion Laboratory was concerned with the engineering aspects of curing and drying. SEEDLING-BED INVESTIGATIONS On steam-sterilized soil the growth of tobacco seedlings with fib. tobaccofertilizer per square yard was better than with lb. or 1 lb., or with -J lb., plus supplementary nitrogen. The recommended practice of covering the seed with sand after sowing resulted in a better germination and growth than leaving the seed uncovered. The distribution of the seed with a watering-can gave as good and as uniform a stand as the usual practice of sowing with dry sand. Commercial aids to transplanting proved of no advantage, either at pricking out or when planting in the field. For the control of worms in seedling beds, derris dust or permanganate of potash proved satisfactory, but bluestone killed off many of the young seedlings. This season there was a marked increase in the number of seedling beds successfully direct-seeded by growers. SOIL STERILIZATION This service is becoming increasingly popular with growers and the 450 cubic yards steamed this year was a record. FERTILIZER EXPERIMENTS A properly balanced fertilizer applied in correct quantities is necessary if maximum yield combined with high quality is to be achieved. Increasing the quality of fertilizer up to 1,400 lb. per acre resulted in improved yield with no reduction in quality, but higher rates gave a falling off in quality and no increase in yield. In combination with phosphate and potash, 4 per cent, nitrogen gave a higher yield than 3 per cent., but adequate potash (at least 8 per cent.) was essential, otherwise quality suffered and maturity was delayed. Low phosphate resulted in reduced growth and later maturity. The inclusion of 2 per cent, magnesium in the fertilizer was beneficial to both yield and quality. A balanced supply of nitrogen from organic and inorganic sources was superior to mixtures where one type of nitrogen predominated. No differences were noticeable in the growth of the crop from high and low levels of calcium. On boron-deficient soils in the district 5 lb. borax per acre resulted in a marked improvement in growth and quality. In a cover-crop experiment, tobacco following oats and vetches produced the highest yield, although the leaf was not as bright as that following rye-corn or Italian rye-grass. Tobacco following lupins produced a poor leaf, dark in colour, and inferior in texture, with much green. Where the quantity of fertilizer was varied in conjunction with the cover crop, large applications of fertilizer following leguminous cover-crops resulted in rank tobacco. The omission of nitrogen from the mixture corrected the position somewhat, but lupins still caused late maturity of the crop. In a trial where the spacing between the rows and the plants was varied, the extra width between rows facilitated working and favoured earlier ripening. There was no reduction in yield, provided the number of plants per acre was not reduced. When the height of topping was varied, low topping reduced yield but produced heavier-bodied leaf of a bright colour. High topping gave the highest yield, but the increase was mainly small narrow tips.

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