WAR ON INSECT PESTS.

New Zealand Herald, Volume LX, Issue 18298, 15 January 1923, Page 8

WAR ON INSECT PESTS.

VALUABLE AID BY SCIENCE. THE VARIOUS METHODS USED ' [by teleghaj'H.— association.]. . :./'/'/;; WELLINGTON, Saturday. ' "The Control; of Injurious Insects,' Was the subject of an ' address /delivered ■at/the Town Hall this evening by.Dr. R. .J. - Tillyard,; F.L.S., .Under the ans- ' 'piceis of the' Australasian /Assbciatiph. for, the'.'Advancement of Science.-, ;Dr../Till-1 ■yard 1 deaU with - various 7 methods'; by. : which , the' control ■; of pests - was. ..'at- . tempted. -These " methods ' might be : .classed roughly .as mechanical, chemical, and biological. / i Under tlie heading of mechanical; methods,", the lecturer-' gave ■ illustrations I ■ of a 'number of interesting devices which \ had made use of, particularly ; in America, with great ;/ success.; of; the most - striking were tarred'paper;, discs : to control cabbage: root maggot, and Mi-. * genious cages for the. control -of the : pin weevil. ■■-:■ :' ■ .'..•::' , -:'. ; ; - ■"/ -/'/ In the chemical- ;, Were, numerous , sprays, • -'vapours?', ; dusts, //and ■■■»ases : for fumigation. /.The;lecturer mentioned particularly the high power, spraying used for valuable forest trees ;in 4 America,"and -the recent development of; spraying from an" aeroplane./ He _ also , mentioned/the; recent development- of /the use of' chemicals in / the ; soil which vapburised;and gave off ; gar.es which re- ; /certain, insects.-- ~,,'" .j u The chief portion of the lecture dealt with biological: methods which; were being: .improved and. brought into/use, and which ; 'consisted- broadly in the. careful scientific study .of an : insect pest and its . own. pumerbus enemies and ;the- ull f h ?^ + # these enemies to;control the: pest. In this -connection, he : gave a detailed hecouht of; . the wonderful work : which has ber/^one. in America- in the control of; the Gipsy moth. This- moth; was introduced -from ' Europe; arid rapidly" began to attack all kinds of,/ forest trees, :; threatening, colpsr sal • destruction .in ".. the : ' Eastern - States. . Huge; sums' of money had been spent; in controlling it,: and from-2Q/to 30.different natural / enemies, , both, and parasitic, - were .now being liberated _ih; countless numbers to help;'to check : the , ■pest..' '■'.' f--':"/' I '." :-. ':'t j .The lecturer gave ,a /short account of i ■ the efforts being undertaken; New Zealand by the Government: Biological/laboratories In Wellington/and by the -Caw- - thron Institute in Nelßon:; Of considerable interest/was/ the detailed;'account given of the introduction,/ acclimatisation, ?aiiddis/. tribution to parts of,N,ewt Zealand of. a valuable .little, /parasite .of thb woolly j aphis known as, Aphebnus ; Mali. ■/ , -i .- The lecturer, by, giving some | instances of urgent; 'problems not '■„;;. yets solved in 'New/Zealand, and emphasised 1 that, only" by continuous /application ; by! 'devoted / bands ■• of scientists, could •/, they.; hope to cope with these extremely-, ditfi-' Cult /problems- which , were /of far /more importance to every. nation than lbs people generally realised," /"'■ f <./ , < ;; /-'- ; i/ : -; : -.: == . ....,. .-.r—:->f.',-.-.