Arborvitae trees are classic favorites for easy-care evergreens that act as hedge or privacy screens. Their sturdiness can withstand heavy snow and also provide a natural windbreak. Arborvitae trees are native to eastern America and are also known as northern white cedars.
Small holes in the bark and sawdust coming from said holes are typically the result of wood-boring pests. Bark beetles often leave sawdust in or near the holes the insects have burrowed into/out of and seek out weak trees that are stressed by environmental stress, improper watering, pruning injuries, or other insect attacks.