638 EXPERIMENT STATION KECORD. 



Old tobacco lands at the station which were deficient in organic mat- 

 ter and produced crops with a large proportion of ground leaves were 

 brought into good condition by the use of green manures, supplemented 

 with commercial fertilizers. Crimson clover was the crop used for 

 turning under. It is seeded immediately after the tobacco crop is taken 

 off in the fall, usuall}" the last of August or first week in September, 

 and turned under the following spring in May. B}' this method of 

 culture the qualit}" of the tobacco has been greatly improved, and 

 within 3 years the j'ield increased more than threefold. When crim- 

 son clover will not do well, cowpeas are advocated. The lack of oi-ganic 

 matter in the soil is considered one of the chief causes of the deterio- 

 ration in quality of the tobacco grown in some sections of the State and 

 the consequent low prices. 



In experiments with commercial fertilizers for tobacco, the use of 

 lime and magnesia in large quantities tended to cause a growth that 

 ripened unevenly and was hard to cure, though the combustibility 

 was slightl}' improved. "On the whole, the application of lime imme- 

 diately before planting tobacco can not be recommended. Phosphoric 

 acid seemed to have but little bearing upon the combustibility, but 

 generally produced a marked increase in the jneld." Potash salts 

 seemed to be the most potent factors in afiecting the composition. 

 The use of forms containing considerable amounts of chlorin resulted 

 in tobacco of poor quality and combustibility, while the use of the 

 sulphate and carbonate forms has improved the qualitj^ and increased 

 the 3-ield. The following fertilizers are considered as being adapted 

 for use in growing tobacco in ^Maryland: Dissolved South Carolina rock, 

 dissolved bone, dried fish, bone tankage, cotton-seed meal, nitrate of 

 soda, sulphate of ammonia, high-grade sulphate of potash, carbonate of 

 potash and magnesia, and cotton-hull ashes. These should be used 

 with green manures. The fertilizer used at the station with good 

 results consisted of 1,300 lbs. of dissolved South Carolina rock, -iOO 

 lbs. of tankage, 100 lbs. of nitrate of soda, and 200 lbs. of high-grade 

 sulphate of potash. Sulphate of ammonia and nitrate of soda are con- 

 sidered particvdarly valuable for use in the plant l)ed for growing strong 

 early plants. 



The relationship existing ])etween the vegetation and good tobacco 

 lands, and also the harmful effect on quality of growing certain crops 

 on tobacco lands, is illustrated by a table showing the relative rates at 

 which chlorin and potash are removed from the soil by certain plants 

 common in tobacco sections. 



The pine lands (commonl}" a species of red pine) arc considered to 

 be the best to))acco lands in Maryland, and chestnut lands stand next, 

 while "oak and hickory lands arc commonly regarded as poor tobacco 

 .soil.'- In the fonner case the ratio between chlorin and potash 

 removed is comparatively narrow, while in the latter it is very wide. 



