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inhibiting action on persisting fruit when applied during the period when it is 

 capable of reducing the set of apples. 



Although we are reasonably enthusiastic about Sevin as a chemical thinner 

 for apples, we need much more experimental data over a period of years before we 

 shall be willing to suggest abandonment of a thinning material like NAD. In fact, 

 NAA and NAD may continue to have a place indefinitely for certain varieties. 

 Also, we need more information concerning the ability of Sevin-thinned trees to 

 induce a "repeat" bloom before it can be given our "blessing". In other words, 

 try Sevin on a comparative basis with older standard methods of chemical thinning 

 before you eliminate any treatment which has given you satisfactory results in 

 the past. 



Sevin appears to be of no value as a peach thinner. 



The 1962 revision of our Circular No. 189, Chemical Thinning of Apples, is 

 now available from the Mailing Room University of Massachusetts as well as from 

 your local County Extension Service office. 



Franklin W. Southwick 



I I I I I I I I I I I I 11 I I 



SELECTION OF EXTERIOR PAINTS 



When liquid paint is applied to an exposed surface and allowed to dry, a 

 thin, elastic film is formed which both enhances the appearance of the surface 

 and protects it against weathering. Appearance is improved by a neat, uniform 

 white or colored surface. The protective power of paint helps to minimize the 

 results of weathering which appear as cupSj warps, cracks, etc., in the thin 

 pieces of wood ordinarily used for exterior siding. The period during which a 

 paint will remain attractive and protective is markedly affected by the compo- 

 sition of the paint. Paint wears through a process called "chalking". Due to the 

 action of light, heat, and moisture, small particles are removed from the surface. 

 If this process occurs at a relatively slow, uniform rate it is beneficial, 

 because it helps to maintain a clean, bright surface. 



Composition , Paint is made up of pipments, which are finely divided insoluable 

 particles, and a vehicle, which is an oily liquid. Both the quality of the in- 

 gredients and the proportion of each in the mix determine the quality of the 

 paint . 



The principal pigments found in most exterior paints are white lead, zinc 

 oxide and titanium dioxide. A limited amount of pigment extenders are also used. 

 White lead used as the only pigment is considered standaid good-quality, but is 

 relatively expensive and exhibits the undesirable feature of discoloration when 

 exposed to hydrogen sulfide fumes. It also becoTnes more soiled by dirt soon 

 after application than most mixed pigment paints. Mixed pigment paints in which 

 the pigment is a mixture of white lead, zinc oxide and titanium dioxide plus 

 'pigment extenders are ordinarily cleaner and less chalky. Where hydrogen sulfide 

 contamination is likely, however, paints completely free of lead pigments should 



