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Show mmuw INJURIOUS TO FRUIT TREES Destructive Scale Insect Pest Attack All Kinds of Plants San Jose Most Injurious. ' Scalo Insects nttuck nil kinds of plants, Including grasses, but nre especially espe-cially Injurious to fruit trees. The more common Injurious species In this .country nre San Jose scnle, oyster shell, bark Ioubo, Bcurfy scale, purple scale, white scalo, rod scale, mealy bugs, etc. The San Joso scalo Is perhaps per-haps the commonost variety. This In-x In-x sect attacks all fruits. On badly infested infest-ed limbs it appears as a grayish scurf, , made up of millions of insects. The young Individual scalo is about hnlf the size of a pin heud, round and black. On the fruit tho scale makes conspicuous red spots. Its dangerous nature Is known to every orchardlst who has it to contend with. It has killed thousands of trees, especially peach,' and Is now sapping the vitality of many thousands more. Scale insects are subject to nttackn of n number of natural enemies, included in-cluded under parasitic and predaceous Insects, fungous diseases and birds. These natural enemies aro usually sufficient to hold the species somowhat In check, with tho exception of tho San Jose scale, which has become a most Important pest. Many artificial remedies havo been ! ried for exterminating scale Insects, the most successful being Bprays of cmde petroleum or kerosene, either undiluted or mixed with water, various vari-ous soap sprays and l.io salt and sulphur wash. All scale Insects may I bo troatoJ by the aarr.o method after I It has been determined by experience I which process is most effective In any particular locality. I In tho eastern states excellent sue- B cess has attended the use'of lime, salt -and sulphur wash, whirh has also been ft Cv ' ,. - d Orchard Destroyed by 3calo. I eery offoctlvo on tho western const I Different results havo boon , obtained I ly different exporlmentors, but ox- I tenslvo experiments ludicato that kero- f seno and crude petroleum aro very re- I liable nnd exceedingly effective Insect!- I cldes against nil scale Insects. 1 It Is generally recommended that J treo3 should bo sprayed in winter or i during a dormant period with these substnncos In undiluted condition or mixed with water. In sonio localities trees havo been Injured by using the spray In undiluted form even in winter. win-ter. On tho othor hand many experiments experi-ments havo been mado which show that these substances In solutions of strengths varying from 15 to 20 per cent, may be safely used upon tho trees in full foliage. Conservative authorities au-thorities on tho subject of the valuo of kerosene and petroloum recommend that these substances be used only In & mechanical mlxturo of water of different dif-ferent strengths up to about 25 per cent. In general it is recommended that spraying with kerosene should be dono only on bright sunshiny days, whdn evaporation is comparatively rapid. |