6 FARMERS’ BULLETIN 636, 
CONTROL METHODS. 
Methods for the practical control of this insect pest are being 
conducted; and while they are still in an experimental stage, the 
following pages give fundamental practices which should be care- 
fully carried out by every alfalfa-seed grower to obtain immediate 
results. 
HARVESTING SEVERELY INFESTED CROPS. 
An alfalfa field is frequently found with such a severe infestation 
by chalcis-flies that the grower considers it of insufficient value to 
be harvested and simply drives in a herd of cows to pasture the 
crop. (See fig. 5.) With regard to the control of the chalcis-fly 
for the protection of future seed production, this is a costly mistake. 
FG. 6,—This ditch bank, 3} rods wide, with its neglected alfalfa, was a place of breeding and hibernation 
for the chalcis fly—a source sufficient for the infestation of surrounding fields. (Original. ) 
Observations show that many of the pods burst open, while others 
are trampled to the ground. Here great numbers of infested seeds 
offer favorable conditions for the hibernation of the chalcis-fly 
larve. These, as mature flies, will infest the seed crop the follow- 
ing spring. Under such circumstances the crop should be mowed, 
removed from the. field, and stacked. It may then be used as rough 
fodder; and if the remaining straw is burned in early spring, the 
hibernating lary will be destroyed. 
CLEANING FENCE LINES AND DITCH BANKS. 
The following facts emphasize the importance of cutting the 
alfalfa along ditch banks (figs. 6, 7) and fence lines, as well as in 
the fields. 
1. The earliest seed pods are found to develop on the isolated and 
vigorous growing plants found in such ‘places. 
I 
