Whenever we
It doesn't look like a J, it's just a section of white pvc (pcv?) pipe sticking up out of the ground with a cap on it. The septic guy told us to buy a huge bag of salt, the kind the farmers use around here (don't know what *they* do with it) and put it down that pipe. He said that would prevent tree roots from growing into the pipe.
Sometimes I miss my old home. This country girl business has it's down-side! Nothing will make you feel more uncivilized than having a screwed up septic system. :) The positives far out-weigh the negatives, though. Have a good one, Gayle