WAR ON RAGWORT

Dominion, Volume 24, Issue 147, 18 March 1931, Page 13

WAR ON RAGWORT

Application of Science BUSH SICK PASTURES Researches at present being carried out under the direction of the Council of Scientific and Industrial Research were reviewed by the chairman, Mr. G. Shirtcliffe, at the last meeting of the council. The chairman stated that the director had reported that Tyris jacobaeae had been successfully established in 'a number of areas in both islands, and at present was attacking ragwort over an extensive area. The Noxious Weeds Research Committee had recommended _ the liberation of Apiou ulicis in specified localities in order to more speedily overcome the difficulties of acclimatisation, and, in this season, its capacity to multiply under New Zealand conditions should be known. Some success had attended the acclimatisation of one consignment which has bred through two generations. Regular and abundant supplies of parasites to deal with ragwort, gorse and blackberry were still being received from Farnham Royal, and a similar arrangement made in respect of Piri Piri parasites from Chile was functioning well. The chairman referred to the success that had attended the treatment of stock grazing on bush-sick pastures by the use of carbonate of iron licks. “This treatment,” he said, “is expected to prove efficacious over a considerable portion of the central North Island pumice area and over land in the Poverty Bay and Northern Hawke’s Bay districts. At Mamaku, the persistent treatment of bush-sick soil with basic slag and superphosphate appears to be combating stock trouble, and to be enabling medicinal dosing of sheep and cattle to be dispensed with. The occurrence of cattle sickness at the Nopaki experimental area seems now to indicate the possibility of the trouble here being classed as bush-sickness, and as resembling that found at Mamaku. Sheep-grazing experiments have been established at Mairoa, where suitable areas have been fenced and top-dressed, and regular analyses of the pastures are now being made.” “Entomolgical surveys of the main exotic plantations in the North Island have been pushed ahead and the range of various harmful types of timber insects defined, thus pointing to where attention should be directed to cntrol measures.”