THE RICE WATER-WEEVIL. 



within a flooded rice field. Having evidently started into growth 

 before the field became irrigated, this crab grass was able to live in a 

 depth of about 6 inches of water. Xot only were the leaves severely 

 fed upon by weevils, but the roots were attacked by larvae. 



APPEABANCE OF ADULTS IN RICE FIELDS. 



Since the growing of rice offers special inducements for the breeding 

 of the weevil, due to the attraction of the plants and the wet condi- 

 tions which they demand for growth, rice has become the favorite 

 food plant of the insect. Directly after the rice fields are flooded 

 the weevils appear and commence feeding on the leaves of the young 

 plants. In southern Louisiana, where much of the water is supplied 

 by canals, the irrigation of rice fields usually begins in the first week 

 of May, but the time of turning on water in different fields is often 

 later, the flooding sometimes not being done until in July to accord 

 with late planting. Wliere water is pumped onto the fields^ a steady 

 flow must be maintained for several days before any large area of land 

 can be inundated.- The flooding of fields in Arkansas is not generally 

 effected earlier than the middle of June. 



By following the application of water in every field the weevils 

 gather most numerously on plants that stand in the depressions and 

 lower portions having the deepest flood. Mr. Hood has counted as 

 many as 18 weevils on a stool and 12 on a single plant. An average 

 of at lea>t 1 weevil to every 5 or G plants in one field has been 

 reckoned by Mr. Newell. Some inclination to avoid direct sunlight 

 during da}^s of hot weather is shown b}^ the weevils, as they seem to 

 prefer positions in the shade of the plants and under the surface of 

 the water. 



They are rather sluggish except when swimming and are disposed 

 to feign death if taken in the hand. They show no inclination to 

 fly during the day and even refuse to expand the wings on being 

 tossed into the air. Passage between separate plants is accomplished 

 in the daytime by swimming. That they can fly for long distances, 

 however, is clearly proven by their attraction to artificial lights at 

 nio-ht. This propensity will be more fully discussed with reference 

 to methods of control. Invasion of fields must therefore be con- 

 summated at night. 



NATURE OF ATTACKS BY ADULTS. 



Rice is attacked in the same manner as other similar host plants 

 and the effects of the feeding by the adults are soon manifested by 

 the appearance of scars on the leaves. (Fig. 1, /.) In the act of feed- 

 ing, the weevil braces its body firmly on the upper side of a leaf, and 

 moving slowly forward in a longitudinal direction either up or down 

 the blade, it chews out the epidermis and produces a scar, leaving 



