38 MASS. EXPERIMENT STATION BULLETIN 369 



between the performance of these oils and the analyses provided by the producers. 

 All the plots treated in June, July, and August showed some cranberry vine 

 injury, but the Cities Service and Colonial products did definitely more harm 

 than the others. The Gulf, Shell, and Atlantic kerosenes burned the vines least. 

 All the kerosenes seemed to have about the same power to kill weeds. 



3. An attempt was made to find more precisely the best ways to apply kerosene. 

 The watering can distributes the oil much faster than hand sprayers and therefore 

 tends to make heavier and more effective applications, but it is harder to secure 

 an even and complete coverage with it. The same kerosene applied to equal 

 areas in equal amounts with a watering can and a sprayer burned the cranberry 

 vines to the same extent. 



4. Bushes of the hoary or speckled alder (Alnus incana) up to 23^ feet tall 

 were killed readily at any time during the summer with half a pint of kerosene 

 poured about the base, and a pint killed bushes up to 6 feet tall, these shrubs, 

 like the coarse bramble, being very root tender to this oil. The foliage of the 

 treated bushes remained green from 2 to 4 weeks and then suddenly turned brown 

 and dry; the coarse bramble is apt to stay green for a month after the treatment 

 and may even bloom before it dies. The small bushes may be killed by spraying 

 the tops with kerosene, but large ones were not much affected by such spraying 

 even when it was heavy. 



5. Ferric sulfate, 2400 pounds to an acre, eradicated sensitive (Onodea) 

 and feather (Dryopteris) ferns completely and 95 percent of horsetail (Equisetum). 

 It did not injure the cranberry vines much early and late in the season, but was 

 very harmful to them in July and August. 



6. Ferrous sulfate mixed 9 to 1 with sodium chloride and placed in single 

 large handfuls at the bases of royal and cinnamon ferns (Osmunda) completely 

 eradicated them with less injury to cranberry vines than was caused by controls 

 previously advocated. 



7. Sodium arsenate, Ij^ pounds in 100 gallons of water applied lightly in 

 August, was very effective in eradicating partidge pea and false pimpernel. 



8. July applications of ocean water showed that 3200 gallons an acre were 

 necessary to completely destroy haircap moss. The moss showed no recovery 

 2J^ months after this treatment. The cranberry vines were not harmed by it. 



No bog flooded by the tide of the September 1938 hurricane had any living 

 haircap moss in 1939. 



9. The conclusion of last year that a fine spray of 100 pounds of sodium 

 chloride in 100 gallons of water is safe to use in treating the wild bean {Apios) 

 if less than 200 gallons to the acre is applied was confirmed. Injury to the cran- 

 berry vines from this spray has always been due to the use of excessive amounts 

 rather than to the concentration. The nozzles must be held high enough to 

 prevent driving too much of the material into thick foliage. 



10. About 100 tests of pulverized and granular cyanamid were made on 42 

 kinds of bog weeds. Wherever the weeds were killed, the cranberry vines suf- 

 fered also. 



Engineering Projects. (C. I. Gunness and H. J. Franklin.) The study of home 

 cold-storage of cranberries carried on in 1936, 1937, and 1938 and the trial of 

 wind machines for protecting bogs from frost, begun in 1938, were continued, 

 the Cranberry Station cooperating with the Department of Engineering. See 

 the report of the Department of Engineering. 



