Melanism has appeared in the European and North American peppered moth populations.
The moth population has declined since then, largely because of a bacteria wilt.
Mating disruption can be used to effectively manage codling moth populations in many cases.
All those swell uniforms would stay in storage year-round, leading to an explosion in the moth population.
In the case of the gypsy moth, a virus is believed to cause periodic "crashes" of the moth population.
Usually the moth populations in Alpine areas are much larger, while those from southern Europe are darker.
This indicates that moth populations would have to be locally adapted for the flowering periods their specific hosts.
If all the yuccas were eradicated or died, the moth population would die out in a single year.
They keep the populations at very low numbers and it is only when they are not strong enough that the moth populations will drastically increase.