DESTROYING STUMPS.

New Zealand Herald, Volume LI, Issue 15520, 30 January 1914, Page 4

DESTROYING STUMPS.

. THE USE OF ACIDS. - MWM OwiNor to a diversity .of '. opinion' as ft> whether'dry : and green stumps oouM ; be ; destroyed with acids, and with a raw to . determining the efficacy of this treatment, the Department'of Agriculture, ■ South - Wales, decided to experiment in this direction. '' These experiments were carried out according to the following design, and' ik«S£S cluded both dry and : green ' stumps:—(l) Dry, 1 pint sulphuric acid; (2) dry, 1 pint ; nitric acid; (3) green £■ pint nitric: acid,. i pint sulphuric acid (4) dry, £ pint nitric'-."/ acid, : J pint sulphuric-acid; (5) greet, pint nitric : acid, :,'i pint sulphuric acid; (6) dry,; i pint' - sulphuric acid, i pint jnitriol|g acid, and (7) dry,' 1 pint nitric acid, 1 pint sulphuric acid. • \ | flßl >. ?Tho stumps treated were of the spotted gfeuj box and ironbark variety, and went from 18in to. 2ft 6itt in diameter. 3 Sole# were ."bored with a 2in auger in she stumps 7 about 18in from the earthline at an angle of 45 degrees to a depth of. 18in.". ' .Each : ?.| • stump was then dosed according to' the I< design/ and the holes immediately, plugged .with green plugs. | Periodical notes 'we»«||| taken as to the action of the acids, and as six months have now elapsed, ■ a sufficient time has been given to prove the experiment a sucoess or.■ otherwise. The whole - of these. stumps were perfectly sound aadpil - solid, also two out of the three varieties, viz., box and ironbark, are extremely fhards® • wood, and if the acid would eat through these stumps then the majority of othas -- timbers would be easy victims. r ' '' "The final .-.examination," the : rap«HjrS§ .states, '' showed that, in the case :of tigS dry stumps, in every' instance the action . of the acids had no appreciable effect, and V-' beyond a very .' slight, crumbling of : the • :■wooden extent about —in the imraedi-' % ate vicinity, of the hole no other effect was -* noticeable. As regards the green stumps,iffi! in both instances " the effect seemed tO-.bi>'iS . slightly better, the wood in tie immediate ■ vicinity of the holes had rotted to a depth 1 ■ of -about'2|in, but beyond that sound wood 1 was found; in addition both stumps ' Had 1 thrown , out vigorous . suckers. : The abovoSl® result clearly proves that sound stomps cannot be destroyed with 'either sclphurio - or nitric acid or both, and these two acids *5? are of the strongest knpwh. The experiment has an additional value, inasmuch . as it has* provided the actual cost per stump as against other . methods. . The;: average cost per stump worked out ; at|l#lH 9d, which includes cost ■of acids and labour paid .- at the rate of 7b per day;;. ' and it >is an open question whether men could be found to work with two such dangerous acids at that figure. , In the event of the success of the acids, the great draw*, . back to clearing land by, this method woip|ff| ho the vast amount of valuable time wasted • in waiting 1 for the stumps to rot away, irrespective of the danger of handling thft . ; acids, and when . time is ' token into t c?iS®| alteration— in every instance timfr4®a raonev—cheaper aad Quicker methods sife# be adopted."