THE PARSLEY STALK WEEVIL. 
(Listronotus latiusculus Boh.) 
By F. H. Cuirrenpen, Sc. D., 
In Charge of Truck Crop and Stored Product Insect Investigations. 
INJURIOUS OCCURRENCE. 
Certain species of curculios, or weevils, of semiaquatic habits that 
normally feed upon wild plants growing in marshy situations, through 
the reclamation and cultivation of such tracts, occasionally attack 
crop plants, and for a season or more accomplish serious damage. 
In many instances injuries are peculiarly local and are not apt to 
recur,” but there is always a possibility that insects of such habits 
may, in course of time, after the cultivation of the same areas, with 
or without the disappearance of these wild food plants, become 
permanent pests. An instance may be cited which came under the 
observation of Prof. F. M. Webster, of this Bureau, in Ohio, in 1894, 
of attack on cabbage by two semiaquatic species of weevil, Listronotus 
appendiculatus Boh., and Notaris (Erycus) puncticollis Lec. About 
50,000 plants were set late in June in a field of swamp land under- 
drained the previous year, and as many as 10 individuals of the 
first-mentioned species were found about single plants, gouging 
great cavities in the stalks. The former, with others of its genus, 
develops normally in arrow-head (Sagittaria spp.) and some related 
aquatic plants. 
It is not surprising, then, that similar injuries should be committed 
by insects of the same class. During the last of July and first days 
of August, 1902, Mr. F.C. Pratt, of this Bureau, noted injury to parsley 
grown at Four Mile Run, Virginia, which upon examination was 
found to be due to both larve and adults of Listronotus latiusculus 
Boh. Injury continued the following season—1903. It thus ex- 
tended over four years—1900 to 1903, inclusive. 
a This holds for several forms of bill-bugs (Sphenophorus spp.), but the most injuri- 
ous species are practically permanent corn pests in certain localities, owing to environ- 
ment; for example, in cornfields planted in the immediate vicinity of marshes, 
rivers, or other bodies of water in which the aquatic plants in which they have their 
natural homes abound. 
14 
=~ ee ee ee 
eee ee Se 
—— 
a 
ae ee ee ee 
a 
