Answer: Salamanders would not be harmful to your garden. Their presence usually indicates a very pristine, clean environment and the disturbances of gardening may chase them away. They are very sensitive to chemical use.
Box elder bugs do not usually harm a garden, in most cases they elect to feed on trees or shrubs as on the edge of the woods and are rarely noticed during the growing season.
Tiny white worms might be potentially harmful, or they might not. For a more specific identification of the worms you might want to take a sample to your county extension.
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