^4 



ki.(>i;i:m stati: iiohtk lltural society 



A record for the month of February 

 1924 shows very much more off-stride 

 blooming and overlapping of first- and 

 second^period sets of flowers, with much 

 more opportunity for both self- and close- 

 pollinations on many varieties than was 

 recorded during the spring of 1925. The 

 cooler and more changeable temperature 

 in 1924, were, no doubt, accountable for 

 this difference in flower behavior. Certain 

 varieties had much more opportunity to 

 set fruit to their own pollen, but as a 

 matter of fact, these certain varieties 

 yielded one of their lightest crops. 



A group of varieties of which Pollock, 

 Tra])p, Estelle and Taft's Golden are con- 

 spicuous examples, have the first-period 

 opening late in the afternoon. They do 

 this consistently day after day. This set 

 may not open until after dark and it may 

 frequently be skipped even on days when 

 numerous other varieties of the A and B 

 groups complete the daily cycle of two 

 sets with decided regularity. When these 

 same flowers open on the following day 

 to shed pollen their pistils are often still 

 white. It seems highly probable that at 

 least some of such flowers may be able 

 to self-fertilize. 



Thus the setting of fruit by isolated 

 trees or by trees of a solid planting of one 

 variety anrl particularly by trees abundant- 

 ly worked by bees in tenting e.xperiments 

 may be expected. It is possible that a 

 peculiar set of local weather conditions 

 may .sometimes favor setting of fruit year 

 after year without cross-pollination. Some 

 varieties such as the Trapj) may have a 

 flower behavior that enables them to be 

 more self- fruitful than are other varie- 

 ties. T'ut even for such varieties there is 



no doubt that a proper interplanting will 

 increase the chances of many more proper 

 pollinations and to this extent insure the 

 production of more uniform crops. 



The varieties are here arranged alpha- 

 betically in two groups. The upper group 

 is made up of those which normally open 

 their flowers for a first time during the 

 forenoon and shed their pollen from an- 

 other set of flowers open for a second 

 time during the afternoon. The louver 

 group is composed of varieties which have 

 a reverse order of flower-opening behav- 

 ior. These have flowers open for a first 

 time in the afternoon and for a second 

 time, shedding pollen, during the fore- 

 noon. 



In the above list those varieties of ]\Iex- 

 ican origin have been marked with an 

 *'M." while "W" indicates West Indian, 

 "G" Guatemalan and "Hy" Hybrids. "E" 

 marks the varieties which start their 

 blooming period early in the season and 

 "L" those which are late in doing so. The 

 early varieties are either all through with 

 their blooming period, or are nearly 

 through, before the late varieties start to 

 open any flowers at all. Hence increased 

 fruit production cannot be expected from 

 an interplanting of an early blooming va- 

 riety with a late one. 



The varieties listed in tiiese two groups 

 are thus placed after careful observations 

 on their flower behavior were made either 

 in California in 1923 or in Morida in 1924 

 and 1925. A daily record continuing 

 over many days was kept of most of the 

 varieties and observations were made on 

 a number of trees of each variety. A few 

 varieties of lesser importance, however, 

 are included where onlv one tree was 



