Question
We have been fighting moles...finding the usual mound of dirt and then putting the gas bombs in the holes.  Now however something new and exciting has invaded.  We have shallow burrows that raise the grass in our yard....looks like blood veins.  No sign of a burrow.  No piles of dirt.  Whatever could it be?  WA State if that helps....

Answer
You still have moles. Dirt mounds are from deep tunnels, veins are from shallow tunnels.
Gas bombs are waste of time. the tunnel systems are too large for the gas to work through the system fast enough to kill the mole. Since you live you WA you can't use the best technique, trapping because the citizens of your fair state voted to ban body gripping traps. This is the problem with listening to animal rights activists. So your only option is to use poisons. Tom Cat mole toxicant by Bell Labs is your best choice. Sadly, animal rights activists force people to use toxicants because they banned the pesticide free technique trapping.

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