1919] Coii-Hodgson: Abnormal Shedding of Washington Narel Orange 311 



The withdrawal of water from the fruits by the leaves has been 

 further substantiated by the use of dry crystals of lithium nitrate 

 injected into the navel end of the youn^r fruits and t(>stin.fr foi- lithium 

 in the leaves proximal to the fruits at different periods following in- 

 jection by means of the spectroscope. These results are summarized 

 in table 7, where it can be seen that withijj a half hour, in spite of the 

 fact that the lithium nitrate was injected dry into the fruit and had 

 to go into solution in the freed cell sap. its presence was shown in the 

 leaves behind the fruits. 



"Water relations of this same general sort have been established by 

 a number of other investigators in plants where such deficits do not 

 constitute a stimulus to abscission. Under this category are to be 

 classed Renner's" "siitigungsdefizit" and the phenomenon of "in- 

 cipient drying" described b.y Livingston and Brown" and established 

 in other plants by Lloyd" and Edith B. Shreve." 



To determine actually the ultimate connection between abnormal 

 water relations of the type noted and the abscission of young fruits has 

 constituted a most difficult problem, and the evidence indicating such 

 a connection has been obtained from several different lines of attack. 

 Although not as conclusive as could be desired, still we believe that it 

 is sufficient to indicate in general the relation between the two. It is 

 hoped that additional evidence can be obtained during the next season, 

 which evidence we were unable to get during our investigation through 

 lack of .sufficient equipment and apparatus. 



As was mentioned in the description of the East Bakersfield station, 

 this orchard is planted to alfalfa, protected by an efficient windbreak, 

 and heavily irrigated. The noteworthy fact, however, is that this 

 orchard habitually hears crops in every way comparable to orchards of 

 the same age and general treatment located near the coast. Although 

 situated only three and one-half miles from the Edison station and 

 having the same exposure, the trees being one year younger, and all 

 conditions similar in every way with the exceptions noted, this orchard 



<3 Experimentelle Beitrage ziir Konntnis dor Wagscrbeweguiig, Flora, vol. 103 

 (1911), pp. 171-247. 



** Kol.Ttion of the daily march of transpiration to variations in tho water 

 content of foliatjo leaves, Bot. Gaz., vol. 53 (1912), pp. 309-30. 



<!> The Relation of Transpiration and Stoniatal Movement to the Water Con- 

 tent of the Leaves of Foiiquierin splcndcim, Plant World, vol. 15 (1912), pp. 

 1-14; Leaf Water and Stomatal Movement in Goss/ipium and a Method of Direct 

 Visual Observation of Stomata in situ, Bull. Torr. Bot. Club, vol. 40- (I9I3), pp. 

 1-26. 



<« The daily march of transpiration in a desert jiorennial, Carnegie Inst. 

 Washington, i'ubl. 194, 1914. 



