326 WALDRON— THE PEANUT 



controlled these pests. Further trouble was experienced, however, 

 unless great care was used in planting and watering. It was found 

 that unless they were brought forward in loose material like sphag- 

 num or well aerated sandy soil, they rotted in one to two days. If 

 pure sand were used, they would rot if kept even moderately wet. 

 The method finally used which succeeded was to plant several to- 

 gether, allowing a considerable degree of aeration. When these 

 produced an inch or two of radicle, they were separated and trans- 

 ferred to individual pots with the cotyledons half exposed. Seeds 

 planted in the shell succeeded well, as this seemed to allow also for 

 free aeration. The ease with which the seeds rot is likely due to its 

 weak protection by the testa. This thin papery coat is easily rup- 

 tured and the embryo, rich in food material, seems to be very sus- 

 ceptible to infection by molds and decay-bacteria. If growth is 

 rapid, however, the increased oxidation gives it vitality to resist. 

 Those who raise peanuts say that good drainage in a loose soil is 

 absolutely essential for success. The plant must start quickly and 

 be kept growing. If planted in the uninjured shell, which is sterile 

 within, there is less likelihood of infection before it gets well under 

 way. A comparison was made by Bennett^^ of growing peanuts 

 from shelled nuts, nuts broken into two parts, dry and unshelled 

 nuts, and unshelled nuts which had been soaked in water for 12 

 hours and buried in the earth below the frost line for different per- 

 iods. The most perfect stand was obtained from nuts planted in 

 broken pods. The results seemed to indicate that when nuts had 

 been thoroughly wet and moist for a short time they would produce 

 a good stand, and save the expense of shelling. This corroborates 

 the author's thought that the seed benefits by free oxygen and pro- 

 tection furnished by the shell in order to start its growth success- 

 fully, at least in anything but an extremely loose soil. 



Later Growth. After the radicle has reached two or three inches 

 the cotyledons are pushed about 2 cm. into the air by the elongat- 

 ing hypocotyl. The hypocotyl often becomes thick and fleshy in 

 its cortex. This is more marked when growth is retarded from some 

 cause, and then the lower end becomes tuberous from a deposition 

 of sugar. The roots of such are not able to utilize the food as fast 

 as it is supplied from the seed. When the soil is light and the tem- 

 perature optimum, the formation of an extensive root system re- 

 sults (see page 323). Under these conditions while the food of the 

 cotyledons is still available, the plant grows rapidly for about 



