22 
REMEDIAL MEASURES. 
Plowing. — Plowing is of great value in changa control, for large 
numbers of the insects are exposed to chickens, lizards, and other 
enemies. In addition, egg chambers are broken up and some eggs 
exposed to the sun, a few hours' exposure to the direct rays of the 
sun apparently preventing eggs from hatching. 
Trapping. — During October, November, and December changas 
take flight in large numbers, most commonly on cloudy, overcast 
evenings. The insects appear in largest numbers just after dusk, few 
flying after 9 or 10 o'clock. The surprising fact was noted in cap- 
tures at lights at Mayaguez and at Rio Piedras (on a single evening 
at the latter place) during October, 1916, that the females outnum- 
bered the males more than two to one. This disproportion fell some- 
what with later captures, but females were still in the majority in 
January, 64 per cent of the total catch belonging to this sex. A large 
proportion of the females captured during the fall were sexually 
immature. 
A season's experience with trap lights has indicated that their use- 
is not generally practical against the changa. It is only on the rare 
occasions when the mole crickets fly in large numbers that it will 
pay to operate a light trap, as at other times the catch will be very 
scattering. Observation will determine whether the insects are 
abroad in sufficient numbers to make the running of the light 
profitable. 
The trap light should be very bright, and the pan of oil and water 
placed beneath should be as large as can be had. As the mole cricket 
is not attracted to the light, but only to its vicinity, it would pay 
in case only a small pan is available, to have the changas that fall 
outside the receptacle picked up. It is useless to keep the light going 
after 10 o'clock. 
Large bonfires in the fall of the year are said to attract and de- 
stroy large numbers of the changa. 
Traps made by sinking wide-mouthed bottles in the earth up to the 
mouth were found to be useless, even when baited with cornmeal. 
Burlap bags are said to be successfully used as traps for mole 
crickets in the Isle of Pines. The bags are laid flat on the ground, 
inspected early each morning, and the crickets found under them 
are killed. Some writers state that mole crickets congregate be- 
neath compost heaps and can be captured there in large numbers. 
Flooding. — It may sometimes be found practical to flood areas 
easily reached by irrigation canals. Flooding formerly practiced i 
1 According to Mr. Holger Johansen. 
