50 MARINE PRODUCTS OF COMMERCE 



doing this is to place rows of bamboo brush or horizontal rope nets tied to stakes so 

 that the rope is in the intertidal zone. These forms of attachment surface, placed 

 in the water in mid-September just before the season's first plants appear, are soon 

 covered with Porphtjra. 



Cultivation of nori in Tokyo Bay originated in the 1670's, but was not widely 

 practiced until about 1800. As early as 1901 over 2000 acres of ocean floor were 



Fig. 5-1. Rhodijmenia pal- 

 mata, the edible seaweed, 

 dulse. 



used for growing Porphyra; in recent years more than 12,000 acres are cultivated 

 (Tseng, 1944). 



Harvesting of nori begins each year in November or December and successive 

 gathering is done, as often as growth permits, until April, when growth ceases and 

 the remaining plants degenerate. Fresh nori is carefully washed and pounded to 

 remove impurities and dried in the form of sheets. First-quality nori is jet-black 

 and lustrous when dry. Japan's annual production averages 800,000,000 sheets, 

 half of which is produced along the shores of the Chiba prefecture in Tokyo 

 Bay. The total retail value of the average annual production is about $6,000,000. 



To the average Japanese nori is a breakfast stand-by although it is often served 

 at other meals, also. One popular preparation is "rolled rice balls," in which vine- 

 gared rice, vegetables, and mashed prawns or eggs are rolled in a sheet of nori 

 which is then sliced into servings. Nori is also eaten by cutting the sheets into 



