The Bulletin. 39 



If this is true with coHard, it is still more true with cabbage, which 

 forms a tight head, the outer leaves of which protect all the inner parts 

 so that the poison does not reach them. In treating cabbage which are 

 forming the heads the poison will get only on the outer leaves, and 

 these outer leaves are always stripped off by the housewife before the 

 cabbage is cooked. So here the amount of poison that might possibly 

 be in the cooked vegetable is even less than with collards. 



There is a peculiarity about the growth of cabbage that seems almost 

 as if designated to permit us to use poison safely against these Avorms, 

 and that is that the cabbage forms its head from the inside. The broad 

 rough outer leaves (the ones which get nearly all of the poison) do 

 not "fold together to make the head. The head grows from within, and 

 these outside leaves are all the time being pushed out and shed off by 

 the plant. So a cabbage plant which is protected by poison during its 

 growth has almost no poison at all on the head itself, and by the time 

 the outer leaves of the head are removed and the head quartered and 

 washed at the kitchen, it would take a very close chemical analysis to 

 reveal even a "trace" of arsenic. 



In Kentucky in 1901* cabbage sprayed as much as four times with 

 paris green and water, were chemically analyzed, but only a "trace" 

 of poison was found, not enough to poison a person under any circum- 

 stances. In 1902 and 1903 similar tests were made without finding even 

 a chemical "trace," and in 1903 the outer leaves alone were analyzed 

 separately, but there was not enough poison to be measured by the ex- 

 acting processes of chemistry. The fact is it takes only an infinitely 

 small quantity of paris green to kill a cabbage worm, and practically 

 all trace is gone before the cabbage is eaten. 



Mr. Chittenden says:;}: "The use of arsenicals (Paris green, etc.), 

 against cabbage worms is almost universal in the United States, although 

 growers are sometimes loath to acknowledge the fact. There are no 

 authentic recorded instances known to the writer of poisoning: from 

 the consumption of cabbage treated with an arsenical." 



Dr. Jno. B. Smith, of "New Jersey, says: "The cabbage heads from 

 within, that is to say the leaves unfold from the center of the head and 

 do not fold together to form it ; therefore, whatever poison is put upon 

 the plant can fall only upon the outer leaves, and not a particle gets 

 into the head itself." (Economic Entomology.) 



From all of which we are certainly safe in the conclusion that light 

 applications of Paris green either as dust or as a spray can be made at 

 any time while the plants are growing without any injury or danger 

 whatever to the person who finally eats the cabbage. 



*Bul. No. 114, Kentucky Experiment Station, by H. Garman (1904). 

 tCirc. No. 60, Bur. Ent., U. S. Dept. Agr., p. 7. 



