CHE REFERENCE LIBRARY - ZetaTalk

fall prematurely, thus retarding the development and growthof the plants. Not only dots this condition rdx it necessaryfor a longer time to t*lapse before the stock is salable, butpremature dcfoliat ion also prevents proper maturation ofthe trees and n~akcs them less able to withstand winter injury,a(lvcrs;e conditions cnc~ountered in stx)rage, and the like.Mtdhcts cwninitrd~~ pra&& for the prevention of diseasesof cjl(ltJr and maturer plants are in many cases not appli-DDE? to tlitl smtdlcr st.cx*k in the nursery, while in manyc’ascs certain mt~tllods of control can be employed in thenurstxr>. whic4r UNII~ not be us4 in the treatment of matureph Ilt 5;.( )W of the importimt prohlems confronting the nurserymanis it satisfac~tor~ mCans of applying t,lie various fungicides andi nst’&ides. An a,pparatus is desirable l3a.t will apply themateri:! with that least, inc’onvtGenc’e, permitting the workto bc ptlrft-rrrned wit 11 considerable rapidit,y on a wide acreageand as ccollc,lnic~i111?- as possible. The materials may be appliedin ;I powdrred form with air used as a carrier, or as aspray- with water as a c*arrier.For spra>-ing tmrsq- stock, there are numerous handspra>*ersthat c’an brb used for small plantings, but there is nopower ma-lcGne on the market t.1la.t is entirely satisfa,ctory forlarge :lurstlrl\- work. It is difficult to build a machine that canbe transported o\*er tall nursery t.rees. On the other hand,the narrow $pac’e separating the nurser>’ rows makes it difficultto construcht 11 sprayer tShat will run between the rows.With the spra)yerx that have been used, only a relatively smallamount of stock can be covered within a given time ; this notonly increases t,he expense? but in many cases it is impossibleto cover all of the suscheptihle st,ock before it is too late forthe application to be effective.Most of these difTiculties a,re overcome when the materialsare applied in t,he powdered form. by means of a dusting ma-