FEEDING OFF AND SMUT.

Otago Witness, Issue 3098, 30 July 1913, Page 17

FEEDING OFF AND SMUT.

The Roseworthy Agricultural College in South Australia has been making instructive trials regarding the benefits, and otherwise, of feeding-off green cereal crops. As early as 1905 portion of a crop of 60 acres of barlev was cut down for green feed in tho spring after the appearance of the heads. At harvest time, although the bulk of tho field was literally smothered in smut, | not a single affected head was to bo seen on the area that had made a second growth. I The fact was noted with interest, and, therefore, in subsequent years, careful experiments were made to sec if tho same results could bo reproduced. Wheat, oats, and barley, unpickled, were sown, and portions wore cut at different periods when green, and portions were left to mature without hindrance. Before mentioning the results it should bo pointed out that tho smut parasite is interna! to the host plant throughout the growing period of tho latter. It dors not make itself externally apparent until some time after the appearance of tho oar of the cereal, when it assumes tho characteristic appearance familiar to every wheat or barley grower. In other words, tho parasite finally concentrates in tho ear, where j it throws off millions of black spores. | The results obtained in the Roseworthy ' experiment with feeding off against smut convey a hint to cereal-growers. Five plots were tested —one was not cut, one was cut on June 26, one on July 6, one on July j 18. and one on J;<S.Bs. • In each cut plot > was a diminution | in numlior of smut-infected plants, the July . 13 cutting showing only 42 per cent, of 1 them as compared with 100 in No. 1 plot. I Say* the Roseworrhy report: “The cutting back of a cereal crop, even as late as tho end of July, but before tho unsheathing of the ears, will not have the effect of eliminating completely all traces of smut or hunt from the cron. The cutting back of a cereal crop oven as early as the end of June will have the effect of reducing considerably the proportion of smut-affected plants present at harvest time. The reduction in the; number of smut-affected plants ! is all tho moro pronounced the later in tho season the crop shall have been cut down. In this connection in our expert

meiits this reduction in numbers varied in a descending series from 14 per cent, to 53 per cent, of the smut-affected plants present in the plot that had not been cut down.” While feeding off may not increase the yield of grain or hay in ordinary crops it is distinctly advantageous, at least, to tho return of grain where tho winter growth is too rank, and it may afford a measure of protection against smut.