SUCCESSFUL TRIAL OF BLACKBERRYKILLING CHEMICAL

Gisborne Herald, Volume LXXVI, Issue 23041, 3 September 1949, Page 8

SUCCESSFUL TRIAL OF BLACKBERRYKILLING CHEMICAL

A chemical found by chance to be effective against bramble in America has been undergoing highly satisfactory trials in the Taranaki district, where it has been effectively killing out blackberry.

Farmers and research workers from all parts of New Zealand and Australia have been watching and waiting for the results of the trials, for blackberry has laid waste many thousands of acres in both countries. Experiments have been carried out in Taranaki before sending the chemical to other parts of the southern hemisphere for trial. The effect on blackberry sprayed locally, states the Taranaki Daily News, has been slow but sure. The foliage wilted and the normally green stems first became blackened then after .about a month it changed to a greyish-white colour and was found to be dry and brittle. Effect on Large Bushes It was found that the effect on the large full-grown bushes was the most spectacular, the large, canes being easily broken and snapping cleanly. When roots were dug up and examined in one of the trial areas, they were found to be easily pulled out. the roots themselves being dry and brittle. The bush was therefore presumed to be dead. Experiments have shown that large bushes should be treated rather than small regrowth. which does not have sufficient top growth to absorb enough of the spray to have the maximum effect on the large root system. It has been found, too. that the majority of the spray was absorbed through the stems rather than through the leaves of the blackberry. Large volumes of total liquids per acre must be used in a machine that produces a high pressure to drive the spray past the leaves and on to the stems. Time of Application Apparently the time of application will influence future work on blackberry. So far it has responded best to mid-summer to mid-autumn applications. rather than to early spring applications.

The latest group of trials to be laid down include stump treatment of freshly-cut blackberry. This method has proven very successful in America at any time of the year. A single, but thorough wetting of the cut surface and bark down to the ground should ensure excellent control. This latter method has still' to be tested thoroughly before it can be recommended for general use. The killer, in the form used in this work.’ is an oily liquid that will emulsify with water, forming a milky fluid. It is non-corrosive to soray equipment, does not constitute a- fire hazard and is non-poisonous to livestock and humans. A gallon of the commercial preparation of the chemical is necessary to sorav an acre of blackberry This gallon should be mixed with 80 to 100 gallons of water.