Recent Research Work

New Zealand Journal of Agriculture, Volume 99, Issue 2, 15 August 1959, Page 103

Recent Research Work

TRIALS WITH THIRAM AS SEED AND RIPENING GRAIN PROTECTANT

As Bird and Slug Repellant on Seeds HTHE commercial fungicide thiram has been used overseas as a bird repellant, the method being to wet the seed in an asphalt emulsion containing one part of asphalt to three parts of water and then to coat the seed with powder containing, one half of thiram and one half, of an inert ingredient. Preliminary tests have been carried out at the Department of Agriculture’s Rukuhia Soil Research Station on this use of thiram as a bird and slug repellant on seeds. The method used was to make the seed just sticky , with rubber solution diluted with an equal quantity of white spirit and to mix the commercial thiram powder with the seed until it was dry and free running. The mixing could be conveniently done in a concrete mixer. The seed was then aired for a few hours before being bagged. A quarter pint of diluted rubber solution was adequate for 10 to 15 lb of large seed such as maize, peas, or wheat, and thiram powder equal to one tenth of the weight of the seed was used. This is probably more than necessary. After sparrows had been fed on barley and peas until a flock was in regular attendance, small areas of barley and peas, both treated and untreated with thiram, were sown. The untreated seed was completely removed, while the treated seed was apparently , untouched and germinated well. Two small bare areas adjacent to long grass were oversown with treated and untreated subterranean clover. Slugs destroyed most of the untreated seed, but no damage could be observed on the treated area until well after all . seed had germinated, when heavy frost lift destroyed the trial. Thiram is probably injurious to inoculants,: but slug damage is such a big factor in the success of oversowing that where inoculation may not be critical thiram as a slug repellant is well worth a trial. —T. F. SOUTHON, Rukuhia

* • . . ■ . * . ... * * To Prevent Losses in Ripening Grain RIPENING grain crops are often attacked by birds, with resulting loss of grain. A bird repellant that could be used to protect these crops would therefore be very useful, particularly in experimental work where compara-

tively small, often isolated, plots, very subject to bird attack, are used. In 1958-59 several trials were conducted during summer and. autumn in various localities to test the effectiveness of thiram as a repellant. The results achieved, however, were not very promising. Sometimes the expected bird attack did not occur, and at others extensive bird damage occurred in both treated and untreated areas. It is possible that in the latter cases rain washed off the treatments. Thiram was applied at 4 lb per acre of 100 per cent material as a spray with water. A “sticker” was used in the spray to give additional adhesion. The time of application was, generally, at the milky to early dough stage. The most detailed trial was conducted at Invermay Research Station, when three treatments were compared on wheat, namely control (untreated), thiram, applied on 31 December, and thiram, applied on 31 December with repetitions after each appreciable rainfall (actually applied on 31 December, 16 January, 4 February, and 13 February). When the last treatment was applied no traces of the previous applications could be observed. Plots were sampled for yields on 2 March, and it was observed that not much bird damage had occurred in any plots, and there were no visible differences. This was confirmed in the yields from threshing. At Winchmore four small plots were treated . with thiram on 5 December, when wheat was in the milky stage. At this time sparrows were observed feeding on the wheat. On 12 December only light damage had occurred. However, on 17 December after three wet days (a total of 1.05 in. of rain), severe bird damage had occurred on both treated and untreated areas. At Marton wheat plots in the early dough stage were treated on 18 December. There was no obvious bird damage at the time of application nor was any observed for some time after. Heavy rain which was followed by a-long period of unsettled wet weather no doubt removed much of the thiram which had been applied. At Rukuhia Soil Research Station heavy bird damage was occurring in a 'wheat trial when the grain was immature. A small area was sprayed with thiram to repel the birds, but it was observed that though the damage might have been delayed, the effect was only temporary. Barley which was being stripped by birds was also treated, but ineffectively.

—K. COTTIER,

Wellington