2 BULLETIN 830, U. S. DEPARTMENT OF AGRICULTURE. 



Ridley 1 shows that careful picking aiid handling, together with 

 the prompt and thorough cooling of strawberries, reduce losses in 

 transit. 



Stevens and Wilcox 2 in a later paper showed that picking the 

 fruit in the cool of the day decreased the losses from decay. They 

 also found that washing strawberries picked during the hottest part 

 of the day resulted in less loss from leak caused by Rliizopus nigricans 

 than when the fruit was shipped without washing. This was con- 

 sidered to be due to the fact that the berries were cooled by the 

 evaporation of the water from the surface. These writers state that 

 "berries picked in the early morning are cool and less likely to decay 

 than those picked in the heat of the day." 



From these investigations it is evident that uninjured fruits are 

 not so liable to decay from fungous infection as those which are 

 injured and that fruit cooled as soon as possible after harvesting or 

 picked when cool is less likely to become infected. 



DESCRIPTION OF THE METHOD EMPLOYED. • 



The present investigation was undertaken to see whether small 

 fruits when cooled were less liable to injury than if picked or handled 

 when they are warm. The small fruits used in the experiment were 

 black raspberries, red raspberries, blackberries, and strawberries. 

 Cherries were also used. Most of the fruit was obtained from Arling- 

 ton Farm, but for a part of it the writers are indebted to the hor- 

 ticultural department of the Maryland State Agricultural College. 



The resistance of the epidermis of the fruit to wounding was deter- 

 mined by means of an apparatus which had been used in measuring 

 the pressure required to puncture the tissue of potatoes. 3 (Fig. 1.) 

 This apparatus consisted of a modified Joly balance. To the lower 

 end of the spring of this balance was attached a metal rod which 

 passed through a short glass tube attached to the upright stand of 

 the instrument. Hairlines on both the tube and rod made it possible 

 to determine the point at which tension on the spring balanced a 

 given weight. At the end of this metal rod a glass rod was attached, 

 to which was cemented a small glass needle with rounded end. The 

 weight of the rod and needle was, of course, within the capacity of 

 the spring. In operating this apparatus the fruit was placed on 

 the stand of the instrument in a suitable holder and the stand was so 

 adjusted that the surface of the fruit was just in contact with the tip 

 of the needle when the two hair lines coincided. The tension on 



1 Ridley, V. W. Factors in transportation of strawberries from the Ozark region. IT. S. Dept. Agr., 

 Bur. Markets Doc. 8, 10 p. 6 fig. 1918. 



2 Stevens, Neil E., and Wilcox, R. B. Further studies of the rots of strawberry fruits. U. S. Dept. Agr. 

 Bui. 686, 14 p. 1918. 



8 Hawkins, Lon A., and Harvey, R. B. Physiological study of the parasitism of Pythium debaryanum 

 Hesse on the potato tuber. In Jour. Agr. Research, v. 18, no. 5, p. 275-298. 1919. 



