OCR Text |
Show EARLY SPRAYING i DOES MOST GOOD1 George King, Assistant Entomolo gist of Experiment Station, Gives Some Advice. Early spraying is the best time for dormant spray ing according to Mr.! George . King, assistant entomologist; Experiment Station, Utah Agricultural Agricul-tural College, who Btote3 that the ab-' cence of foliage in February andj Mnrch permits a more thorough application appli-cation and the use of stronger insecticides insec-ticides than would, bo safe on trees in , leaf. ''Dormant spraying is directed n-gninst n-gninst these pests which may bo mosti effectively controlled during their ( resting stage" says Mr. King. "Spray-1 ing mny be done any time after the leaves drop in the fall, or the winter when the weather warms up to 10j degrees, Fahrenheit, but it is prefer-oblc prefer-oblc in early spring when tho buds, ore swelling as at that tiino insects ( become active and the spray is more fatal to them. "All sprays used on dormant trees' kill insects by contact rather than by, i poisoning them through tho digestive tract. For this purpose many sub-1 stances are used, nil of which cither interfere with tho insects breathing or corrode its body or both. Those commonly used for dormant spraying are lime-sulphur, kerosene, or othori misciblc oils and sonp sprays used' undiluted or in emulsion. "Of these tho lime-sulphur is disagreeable dis-agreeable to prepare and use; it spreads and penetrates poorly, but is safe, efficient, and has becomo the standard dormant spray because of its wide range or usefulness in controlling con-trolling nenrly all insects that other dormant sprays control. It remains on the trees in an active condition extending its usefulness into the summer sum-mer a a destroyer of insects, fungi, and lichens which otherwise infest them. Nothing is more effective in1 controlling San Jose scale and ninny i related scale insects, the penr tree psylla, blister-mite, spider mite, nndi several other pests. "For thoso witln small orchnrds it will probably always al-ways be cheaper and better to use the commercial product, being careful to follow accompanying dirctions; however how-ever lime-sulphur mny be prcpnred satisfactorily as follows: Use five lbs. of fresh stone lime (00 per cent or more calcium oxide;) ten lbs. sulphur (commercial ground;) about five gallons gal-lons of water. Place a gallon of wn-I wn-I ter in the cooking vessel and start to bent it; the lime and sulphur is then plncod in the vessel (the sulphur may be made to paste to avoid lumpincss) as most convenient. Stir them vigorously vigor-ously while the lime is sinking. Add water as required to slack tho lime 'properly until theh C gallons are used. 'Boil about 50 minutes, stirring frequently, fre-quently, after which the solution should be of a dark amber color. The total volume of the finished product should be five gallons. After straining strain-ing out all insoluble material this I stock solution enn be kept indefinito-ily indefinito-ily if air is excluded from it. I "For accurate work with limc-sul-! phur a Baume hydrometer is a necessity. neces-sity. The formuln given should yield a solution about 2G degrees Baume and for spraying Snn Jose scale should bo used one part to five of I water. By using the same formula with but G-8 as much water the finish-icd finish-icd product will be more concentrated and should measurq 3 1-8 gallons and jhnve a concentration of about 33 deg. I Baume. For use dilute this strength one part to seven of water. These j strengths are for San Jose scale and are loo strong except for dormant trees. I "Where aphfds are troublesome it is often practicable to delay the dormant dor-mant spraying until just as tho buds are breaking, and by adding forty per cent Nicotine Sulphated to tho lime-' lime-' sulphur at the rate of three-fourths j pint per 100 gallons of spray, effect n combination treatment for both scale and nphids. "In order to be successful, spraying must always be done thoroughly. It is always necessary to reach every I part of tho tree and for mnny of our worst pests the application must be mnde at a definite and often limited time. The fruit grower owes it to himself to study tho pests affecting his trees sufficiently to ennble him to inteligently combat them." |