The Flower Behavior of Avocados with Special 



Reference to Interplanting 



A. B. Stout and E. M. Savage 



With a selection of varieties on the 

 Ijasis of their relative flower behavior, in- 

 terplantings of avocados can be made 

 which will greatly increase the chances 

 for the proper pollinations necessary for 

 fruit production. It is the purpose of 

 this report to present records of the flower 

 behavior of numerous varieties which in- 

 dicate why interplanting- is desirable and 

 how the selection of varieties for the most 

 successful interplanting is to be made. 



With the exception of the variety Col- 

 linson, to l)e discussed later, all varieties 

 and seedlings thus far studied by the 

 writers, have flowers that appear to be 

 fully perfect. They shed pollen under fa- 



*Thi,s report pertains particularly to studies 

 made in Florida during February and March, 1925. 

 in which Dr. A. B. Stout of the N. Y. Botanical 

 Garden and Mr. E. M. Savage of the U. S. 

 Department of Agriculture co-operated. The ex- 

 penses of Dr. Stout were met by Dade County 

 through its Farm Bureau. The County Agent, 

 Mr. J. S. Rainey, various officers of the Florida 

 Avocado Association and numerous growers of 

 avocados co-operated very fully in the investi- 

 gations. This report also draws freely of previ- 

 ous studies by the authors, those of Dr. Stout 

 in California in the Spring of 1923, and those 

 of Mr. Savage in Florida during the Spring of 

 1924. Certain portions of this report and espe- 

 cially the discussion of interplanting draws freely 

 and to the point of exact quotation from articles 

 previously published. The j)lan has been to as- 

 semble in this one article all the most important 

 data nf)w available on flower behavior of avo- 

 cados with advice regarding interplanting. — The 

 Authors. 



vorable conditions of weather and they 

 appear, with possibly a few exceptions 

 among seedlings, fully able to function in 

 the development of seed and fruit. But 

 in avocados self-pollination of individual 

 flowers is, for most varieties at least, 

 greatly restricted or even impossible. Each 

 avocado flower has normally two distinct 

 periods of being open. It is during the 

 first period that the pistil of the flower 

 is most ready for receiving pollen but 

 it is during the second opening that the 

 pollen is shed. The api^earance of the 

 flower during the two openings is indeed 

 very dift'erent. At the climax of the first 

 opening the pistil stands erect and alone 

 and the stamens lie at right angles to its 

 basie. 



During the second opening the stamens 

 are decidedly larger, they stand more near- 

 ly erect and the valves of the anthers 

 open, bend upward and carr>' out the pol- 

 len and then insects may complete its 

 distribution. The length of the interval 

 between the closing after first-o|>ening 

 and the shedding of pollen in the second- 

 opening (lifters for varieties. When this 

 interval is from 12 to 16 hours as in the 

 Trapp. some pistils may remain in a con- 

 dition suitable for fertilization by self- 

 pollination. But for many varieties the 

 climax of the maturity of the pistil of a 



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