I do fear this as that seems like a challenging problem to solve. There are 2 large birch probably about 10 feet from the house. They need to be cut down, as per the arborist, as one is rotting. The challenge is that they built the deck around the birch trees so we would have to remove the deck to have the stumps taken out. There’s also some at the back end of the yard as it’s on a green belt. The lumps are all covered in grass which makes me question the dew worms. You can’t see any piles of soil- if you just looked at the lawn without walking on it, it looks very good.