10 btjli.eti:n" 824^ r. s. depaetiment of agriculture. 



1891 reported that Pyrethruin seed sown in the fall grew, and that the 

 plants blossomed a little, although the year was the hardest for 7 years, 

 according to old residents. Shinn (256), of the same station, in 1897, 

 reported on the cultivation of Persian insect powder plants (apparently 

 P. roseum) as follows: "Plants endure the winter and bloom freely. 

 They do not grow rapidly, however, and the culture would probably 

 not be profitable here." In the same report (p. 72) Pyre thrum is 

 suggested as worthy of trial as a plant suitable for cultivation on alkali 

 soil, but no experiments seem to have been made to test this idea. 

 Both Pyretknnn roseum and cinerarisefolium are mentioned as being 

 well established in the garden of the Southern California Culture 

 Substation, in Chino Valley. Schrenk (248), quoting from Sender's 

 "Die Tropische Agrikultur," describes the cultivation of C. cine- 

 rarisefolium in California by Dalmatians who had settled there. 



Within the past few years the C. cinerarisefolium has been success- 

 fully cultivated at Madison, Wis., and at the Arlington, Va., Experi- 

 mental Farm of the United States Department of Agriculture, and 

 Halsted (112, 113) has grown hybrids of C. roseum and the field daisy 

 (<7. leucanthemum) in New Jersey. As said before, however, Cali- 

 fornia is the only place in this country where the cultivation of 

 Pyrethrum has continued on a commercial scale. 



Summary. — At present insect flowers are cultivated commercially 

 in Dalmatia, Montenegro, Japan, Australia, Algeria, and California. 

 The first three countries produce nearly aU the flowers that enter 

 into international trade. In 1907, 2,882,000 pounds, and in 1908, 

 2,615,000 pounds of insect flowers were exported from Austria 

 (165). Japan, in 1913, exported 349,225 pounds of insect flowers 

 and 211,012 pounds of insect powder, and in 1914, 819,612 pounds of 

 the flowers and 256,567 pounds of the powder (251). As for the 

 wild insect flowers, it appears that Montenegro is the only country 

 where they grow abundantly enough to be of commercial impor- 

 tance, and even there the quantity is small, as, according to Jiittner 

 (150), the whole Montenegrin production of wild flowers amounts at 

 most to 15,000 kilograms (33,000 pounds) each year. 



PREPARATION OF INSECT POWDER. 



In one of the earliest accounts of insect powder (5) it is stated 

 that the dried insect flowers are rubbed to a coarse powder with the 

 hand, and then ground fine in a small miU. Willemot (294) gives 

 directions for the pulverization of insect flowers in a mortar by 

 simply rubbing them with a pestle. In order to prevent the escape 

 of powder, the mortar should be provided with a leather covering 

 through an opening in which the pestle moves. 



Coquillet (55) describes the manufacture of Buhach from the 

 flowers of CJtrysantTiemum cinerarisefolium in California as foUows: 



