How low do I bury a direct bury phone dash?
Answers: The deeper the better. But, I think 6 - 12 inches is typical.
Shallow lines are other subject to getting punctured or cut by back-yard digging... so deeper the better. Maybe document the route you lay it to prevent accidental adjectives by digging. Make sure there are no rocks against the procession when layed down. Rocks can eventually dig or rub into the procession. If a line bring punctured, it is subject to water ooze and then chagrin and service problems...