654 EXPERIMENT STATION RECORD. 



the principal investigation carried on in the greenhouse. Some horti- 

 cultural work included in the report is noted elsewhere. 



During the year the experimental plat for botanical work was 

 increased to nearly 2 acres. Several hundred specimens were added 

 to the herbarium during the season, and some attention was given to 

 a study of weeds and the determination of foreign matter in commercial 

 seeds. 



Experiments with turnips (pp. 294-309). — After summarizing the 

 experiments for the previous four crops the author reports upon the 

 work done in 1896 for the prevention of club root. Of the various 

 fungicides tried unslaked lime has thus far proved to be the only effi- 

 cient treatment for the prevention of club root of cruciferous plants. 

 It is recommended that it be applied at the rate of from 75 to 150 bu. 

 per acre. This application should be made every other year on land 

 badly infested with the fungus where cabbages, turnips, or allied 

 plants are yearly grown. 



Plat experiments indicate that the fungus of club root can remain 

 active in the soil for at least 2 years, and from box experiments in 

 which the soil was considered free from the fungus it was apparent that 

 manure may be the means of carrying the infection to the soil. 



The author tested 16 species of cruciferous plants to ascertain their 

 susceptibility to club root. Those so tried were candytuft, sweet 

 alyssum. wild sweet alyssum, shepherd's purse, rockcress, wormseed 

 mustard, peppergrass, field peppergrass, stock, penny cress, radish, 

 rocket, black mustard, charlock, white mustard, and false flax. Of 

 these, stock alone was unaffected, while charlock proved most subject 

 to attacks of the disease, followed closely by white mustard. The 

 necessity of keeping these weeds out of fields is obvious. Radishes, 

 rocket, sweet alyssum, and candytuft were least affected. 



Experiments with potatoes (pp. 309-319). — In continuation of the exper- 

 iments of previous years, reported in Bulletin 112 and the Annual Report 

 of the station for 1895 (E. S. 11., 7, p. 780: 8, p. 893), the prevention of 

 potato scab was investigated. The author states that Bordeaux mixture 

 and ammoniacal copper carbonate were efficient to some degree in con- 

 trolling scab. Sulphur took the lead among the soil treatments, and its 

 effect on the soil is claimed to be lasting. Treating seed with sulphur 

 or corrosive sublimate, while efficient in clean soil, will not avail much 

 in badly infested soil. A mixture of 300 lbs. each of sulphur and kainit 

 per acre is recommended as a combined fungicide and fertilizer for use 

 on scab infested lands. 



An opportunity was offered to test the respective value of the bud 

 and stem ends with the middle of the potato when used in planting, 

 also the effect of depth of planting. The superiority of the middle 

 portions over the end cuttings was established, so far as this experi- 

 ment was concerned. It is claimed that planting more than 4 in. deep 

 is not justified on account of greater labor. 



