THE FLOWEIl BEHAVIOR OF AVOCADOS 



169 



some varieties, however, seedless fruits frequently develop to 

 maturity on the trees. It seems highly probable that when fruits 

 do set in abundance many start to develop without proper pol- 

 lination and that the fruits that do remain to maturity and de- 

 velop to proper size are those whose embryos are the products of 

 most proper pollination and fertilization. 



There is little direct evidence, experimental or otherwise, as 

 to the exact kind of pollination which is responsible for the fruit 

 that does mature on avocado trees. There is a long period of 

 bloom with a large number of flowers open day after day, A 

 very low percentage of the flowers mature fruit or in most cases 

 even set fruit. The percentage still remains low when one makes 

 most careful hand pollinations, so this method has thus far given 

 no very conclusive data. Possibly, when flowers are fully func- 

 tional and insects are working most effectively, a few insects 

 make all the pollinations responsible for a full crop in a few 

 minutes, but what these conditions are and when they occur re- 

 main to be determined. It is most probable that these condi- 

 tions are different for different varieties. 



Eemarks on the interplanting of avocados 



It is obvious that the flower behavior of avocados greatly 

 limits the chances for proper self- and close-pollination. If a 

 tree stands alone with no tree of another and reciprocating vari- 

 ety within insect range, there is little chance that many of the 

 flowers will be pollinated at the proper time. 



As avocados are propagated vegetatively, the varieties are 

 all clonal varieties. The many trees of the variety are merely 

 branches derived from one original seedling and when standing 

 together they daily exhibit the same action of flowers. There is 

 no question but that the proper interplanting of different varie- 

 ties of avocados on the basis of their relative flower-behavior will 

 greatly increase the chances for proper pollination and thereby 

 make possible more abundant and more uniform yields of fruit. 



It has been noted that certain avocado trees grown in appar- 

 ent isolation may yield fair crops of fruit. But it is also well 

 known that many such trees have borne few or even no fruits 



