"Leafminers bugs" describe the larvae of moths, flies and beetles that feed on the interior tissue of the leaf of a bug. The damage done by these garden pests to our plants is easy to spot because of the "mines" created as the bugs chews inside the leaf. In some instances the leafminer will cause a light colored blotch on the leaf, in really bad cases the plant will look discolored and/or drop leaves. It is rare that leafminers do enough damage to kill a plant, what they destroy mostly is the aesthetic value of your ornamentals for a short period of time.
How Do They Get In?
Female flies puncture the leaves to either suck on the sap inside the leaf or to lay eggs.
How Do I Kill Them?
It is rare that so much damage is done by these bugs during their life cycle that your plant will die. Most of the time there are enough natural predators, like parasitic wasps, that keep these pests under control. If you have to use an insecticide that is systematically carried throughout the plant. That means that you have to use an insecticide that is absorbed by the plant and carried to the leafs where it will come in contact with the larvae or be eaten by it. Bug spray that work by killing bugs on contact won't have any (if much) affect if sprayed on your plants.
Have Some Time To Kill?
I came across this game for kids on ArborDay.org where try to correctly identify the leaf that is dropped before the falls and eaten by the leafminer larvae on the ground. Correctly identity the leaf by selecting the name from the choices on the right hand of the screen. If three leafs are eaten by the leafminer the game ends. Play the leafminer game.
Leafmining Insects/Chemical recommendations.