48 THE HESSIAN FLY IN THE UNITED STATES. 
COMBINATION OF REMEDIAL MEASURES. 
A little thought concerning the measures which have been discussed 
above, with a recognition of the life-history facts upon which they are 
based, will suggest that the best practical results will be obtained not 
by reliance upon any one method, but by an intelligent adaptation of 
two or more, according to the conditions prevailing for the season. 
These will constitute a practice which can be modified for each year as 
the conditions will indicate. 
With the harvesting of the grain, there is open the policy of burning 
the stubble or plowing it under or allowing it to stand for the exclusion 
of parasites. If the weather is very dry, it will be best to defer burn- 
ing, to allow the issuance of as many parasites as possible, but if burn- 
ing is to be adopted at all, it should be done before fall rains set in or 
the field has grown up to weeds. If rains occur early, burning will be 
best; and in any case the stubble should be plowed under and rolled 
as soon as there is any appearance of a volunteer growth of wheat. 
The chaff from threshing should be burned and the screenings burned 
or fed to stock as early as possible, and care should be taken during 
autumn to plow under and roll the volunteer wheat that springs up in 
the stackyard. If winter wheat is to be planted, strips of decoy wheat 
may be put in to be plowed under at the end of three or four weeks, 
and finally the crop planted at as late a date as practicable, according 
to dates given in the paragraph on late planting. This practice can be 
duly combined with the selection of resisting varieties of wheat and 
the application of fertilizers. 
It will be observed that the modifications are based primarily on the 
weather — whether dry or moist, a condition apparent to everyone, and 
that the suggestion amounts to postponement of burning or plowing if 
dry, or the early adoption of one or both if wet. 
BIBLIOGRAPHY. 
The following list of papers on the Hessian fly includes, it is believed, 
all of importance that have appeared in America and such of the foreign 
works as have an importance to the American student. Of the Ameri- 
can literature, a long list of articles in agricultural papers have been 
excluded as unnecessary in such a list, although the earlier articles of 
this character are well covered. Those appearing in recent time have 
been largely a restatement of well-known facts, without any contribu- 
tion to a knowledge of the insect. Any who may care to trace this 
class of articles further will find full references in the Bibliography of 
North American Economic Entomology, jmblished by the Division of 
Entomology, United States Department of Agriculture. 
(1) Ackerly, Samuel. Au account of the wheat insect in America, or the Tipula 
vaginalis tritici, commonly called the Hessian fly. <(Amer. Mo. Mag. and 
Crit. Rev., August, 1817, vol. 1, pp. 275-279, 3 figs. 
