PLANTATION OF THREE-YEAR-OLD BLUEBERRY HYBRIDS AT WHITESBOG, NEW JERSEY 



These hybrids, photographed in their third year from the seed, were then producing 

 their first commercial crop, seven bushels per acre. The rows are five feet apart and the 

 plants three feet apart in the row, too close a spacing for a permanent plantation (which 

 should be eight by eight feet), but correspondingly more productive in the earlier years. 



inside. In other cases the stems were 

 severed from the root, packed in moss or 

 moist sand to prevent drying, and ex- 

 posed inside or outside the greenhouse. 



From these experiments the fact was 

 definitely established that when a blue- 

 berry plant has completed its active 

 growth of spring and summer, and later 

 in the season has gorged its twigs, stems, 

 and roots with starch and other storage 

 foods for early spring use, it becomes 

 dormant and, shedding its leaves, refuses 

 to grow again at the temperatures which 

 in spring and summer would be most fa- 

 vorable to its growth. 



But after the plant has been exposed 



to prolonged chilling, at a temperature a 

 little above freezing, it is ready again to 

 grow, and then it is that under the in- 

 fluence of warmth, whether furnished 

 naturally by the sunny days of spring or 

 artificially from the rusty heating pipes 

 of a greenhouse, the buds swell and the 

 plant leaps forward in a riot of rejuve- 

 nescence and reproduction. 



One change that takes place in the 

 blueberry stems during the period of 

 chilling is the transformation of the 

 stored starch into sugar. The starch 

 must first be turned into sugar before the 

 plant can use it for food, and that change 

 the chilling accomplishes. In the warm 



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