PLANTING AND SEEDING SEASONS 11 



planting in winter and an earlier closing date in the spring, due to the 

 greater length of the growing season in this zone. Station 18 has such 

 short winter interruptions that it practically offers a continuous work- 

 ing period from fall to spring. Stations 17 and 20 lie in the Lower 

 Austral Zone, which includes the Atlantic Coastal Plain from the 

 Piedmont Region to the ocean and all the southern states south of the 

 Upper Austral Zone. The Sacramento-Fresno Valley in California 

 also is included in this zone. These stations, together with station 19, 

 which is probably influenced by the Japanese Current, and station 21, 

 which lies in the Gulf strip of the Lower Austral, all report a continuous 

 planting season of about the same length, which is uninterrupted by 

 any cold weather. Station 16 reports a long fall season with a short 

 interruption and a short spring season, while station 22, which lies 

 just north of the Tropical Zone, reports a short, uninterrupted season 

 which closes early. 



In the extreme northernmost area, except that of Camden, Maine, 

 the fall planting season does not open early enough, nor does the spring 

 season extend long enough to offset the long winter period of frozen 

 ground, which may extend to five months in the Northern Zone. 

 Thus the total number of working planting days in the Northern Zone 

 may be only 70 or 80 in an average year of not unusual severity of 

 winter, while in the great central portion of the country each of the 

 two seasons may be as much as 50 days long, giving a combined plant- 

 ing season of about 100 working days. In the Southern Zone, where 

 there is no interruption during the winter, the season may be from 115 

 to 150 or even 160 days long, except that the beginning of growth in the 

 spring curtails the season at that end when the Tropical Zone is ap- 

 proached. It should be noted that the farther south one goes the more 

 abruptly the spring growing season opens and the harder it becomes to 

 prolong the planting season by any of the expedients mentioned above. 

 The growing seasons of the southern sections of the United States open 

 rapidly and there is greater danger in the operation of transplanting 

 after leaf growth has started than in the cooler northerly sections of the 

 country. It is also inadvisable to import cold storage plants into 

 such southerly sections much after the time when local stock is in 

 full leaf. 



It is probable that as time goes on much more detailed and complete 

 data will be published regarding safe planting seasons for the different 

 life-zones of the country, thus enabling planters to eliminate nearly all 



