PEAS 339 



effectively for the control of such a pest, and therefore an extensive 

 visitation of the pea louse in any region is a serious matter. A few 

 years ago such an outbreak occurred in the pea-growing section of 

 Maryland, and the indications were that the entire pea industry would 

 be driven from that region. Fortunately, however, the multiplication 

 and continuance of an insect of this character is largely controlled 

 by soil, crop, and climatic conditions, and the pea louse passed away 

 from Maryland almost as completely and quickly as it appeared. 



Pea weevil. This is a small snout beetle or weevil which gains 

 entrance to the pea through the egg, which is deposited in the pod 

 while the pea is in a green state, the larva as well as the adult insect 

 deriving its nourishment from the pea. When the peas are in the 

 green state the weevil cannot be detected, and no injury is caused 

 by the deposition of the eggs. It is in the dry, stored peas that the 

 harm is done. Without the exercise of proper care in the fumigation 

 of stored peas and beans, the weevil may destroy a large percentage 

 of the seed. By the use of bisulphide of carbon in closed rooms, 

 boxes, or bins, the peas and beans can be effectively fumigated and 

 the insects destroyed, after which the seeds can be kept with com- 

 parative safety. This method of treating the seed was suggested 

 many years ago by Professor W. W. Tracy, Sr., and special houses 

 which were built for this purpose are known as Tracy houses. 



Mildew. The mildew of the pea is of considerable economic 

 importance in some sections during certain seasons, as it renders 

 the production of peas out of the question. During the hot weather, 

 when there is considerable alteration in temperature between day 

 and night and the air is charged with humidity, it becomes almost 

 impossible to grow peas because of the mildew. This is more espe- 

 cially true of the fall than of the spring months. In localities where 

 this disease prevails, the growing of peas is regulated to avoid 

 seasons when the disease is most destructive. 



Varieties. The varieties of garden peas are sufficiently numer- 

 ous to meet the requirements of the most exacting taste. As has 

 already been suggested, there is a group of varieties based on the 

 character of the seed (whether hard or wrinkled) and the character 

 of the pod (whether edible or nonedible). A second classification, 

 based on the habit of growth of the plant, has three subdivisions : 

 (i) dwarf plants, (2) medium-sized plants, and (3) tall plants. These 



