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Replanting in a Peach Orchard Where Trees Have Died 



The same procedure as replanting in an old orchard site apply 

 but, because a location where a tree has been removed is small and 

 the locations are scattered through the orchard, a rototiller can 

 be used to prepare a planting site. The fumigant can be applied 

 with a hand applicator and the fumigated area covered with a poly- 

 ethylene tarp. 



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EARLY ETHEPHON SPRAYS FOR FLOWER BUD INITIATION 

 AND RIPENING OF APPLES 



D.W. Greene, W.J. Lord, and W.J. Bramlage 

 Department of Plant and Soil Sciences 



Ethephon sprays to enhance red color development on apples is 

 now an established practice. In our studies with ethephon, we have 

 also been interested in its potential for initiation of flower buds 

 on bearing trees. Our early studies showed that ethephon at rates 

 of 500 to 1000 ppm (1-2/3 to 3-1/3 pt/100 gal) thinned Cortland and 

 Mutsu apples when applied 26 to 44 days after full bloom. No fruit 

 abscission of Mutsu occurred at 250 ppm (5/6 pt/100 gal) when ethe- 

 phon was applied 35 to 44 days after full bloom but flower bud ini- 

 tiation was not increased. In an experiment in 1973 with Early 

 Mcintosh, we found that a combination spray of Alar-85* and ethe- 

 phon applied after the completion of June drop caused no fruit ab- 

 scission, and that increased flower bud initiation was recorded the 

 following spring. In 1974, we expanded our studies on flower bud 

 initiation with ethephon on bearing trees, and included Cortland, 

 Mcintosh, Red Delicious, and Early Mcintosh. Our findings are sum- 

 marized below. 



Early Mcintosh . We failed to verify our 1973 results. Post-June 

 drop applications of ethephon (July 8) at 250 ppm and 500 ppm stim- 

 ulated fruit ripening within a week after application and the en- 

 tire crop dropped prior to normal harvest. Furthermore, unlike 

 1973, the ethephon sprays in 1974 failed to enhance repeat bloom in 

 1975. 



Cortland . The response of this cultivar to ethephon was strikingly 

 different from that of Early Mcintosh. Concentrations up to 1000 

 ppm, applied at the same timing, caused no fruit abscission. Red 

 color enhancement was slight, and only at 1000 ppm did ethephon re- 

 duce flesh firmness. However, respiration studies showed that 1000 

 ppm ethephon clearly stimulated earlier ripening, while lower con- 

 centrations produced a small advancement of ripening and Alar-85* 



*Trade name 



