lyil.J PUBLIC DOCUMENT — No. 31. 227 



to reach its normal size on account of too severe summer heat. 

 It is probable that this occurs most noticeably in the extreme 

 south of the apple region. We have seen evidences of it in 

 the Ben Davis and Winesaj) that were grown about as far south 

 as these varieties are much cultivated. 



The Ojjtinium Mean Summer Temperature. — It is evident 

 from the foregoing discussion that the development of the high- 

 est i)crfection in any given variety is closely related to most 

 favorable mean summer temperatures. In Table 5 is given a 

 list of varieties, with an estimate of the optimum temperature 

 for each sort, and in ..ome cases of their possible range and 

 hardiness with respect to the cold of winter. The list of vari- 

 eties includes all those that are given the double star, indi- 

 cating highly successful varieties, in the list of the American 

 Pomological Society, with a number of additions of varieties 

 that, for various reasons, seemed worthy of consideration. In- 

 asmuch as we consider keeping quality of considerable account 

 with most sorts, the policy has been to prescribe about as low 

 a temperature as will suffice to thoroughly mature a variety, 

 leaving a margin of about 2° for seasonal fluctuations; that 

 is, we believe that any variety may be matured when the sum- 

 mer mean is 2° lower than the one given. This applies more 

 particularly to the fall and winter varieties. We believe, on 

 the other hand, that any increase in the summer mean for any 

 variety, unless it be the earliest ones, will be a disadvantage, 

 though a very slight one, if the rise is not more than 1° or 

 2°. Up to a certain degree the overmaturity of the fruit in 

 a too warm climate may be overcome if the grower will pick 

 at the time of full maturity and put the fruit at once in cold 

 storage. If the heat is too great, however, even with this method 

 the fruit will be inferior in flavor and color, and, in very ex- 

 treme cases, in size. We believe that a departure of more than 

 2° in either direction from the temperatures given will be a 

 noticeable disadvantage with any of the winter varieties. This 

 remark will apply less to the fall sorts and still less to the sum- 

 mer varieties ; or, to put it in other words, the earlier the variety 

 the greater may be its range of temperature without marked 

 deterioration of the fruit. There are doubtless errors in the 

 case of some varieties, concerning which we have limited infer- 



