We purchased this boxwood from a garden center last fall. It sits in a raised mulch bed with silt, sand, minimal clay soil so drains fairly well. Mulch does not cover root area heavily. Lots of rain this last month. Noticed these thinned straw colored leaves. On close look, almost linear black spots are on underside. I believe this is Macrophoma Leaf Spot, and read it to be a low virulent fungus, but I am no expert. Plant stems do not seem blackened. I'm planning to cut out the affected areas. The sun is on the way and they are predicting a lot of 90 plus days this summer. Does this sound like a plan if it is Macrophoma? Your advice? Thank you for your help.