Hi Anna Marie and thanks for your question about your boxwoods. I see some grey leaves but the pictures blur when I try to enlarge them, so I'm going to send you websites with my 3 best guesses and you can see which one of the pictures matches your symptoms best.

Boxwood blight:
https://pnwhandbooks.org/plantdisease/host-disease/boxwood-buxus-spp-boxwood-blight
Canker
https://pnwhandbooks.org/plantdisease/host-disease/boxwood-buxus-spp-volutella-leaf-stem-blight-canker
Phytophthora root rot
https://pnwhandbooks.org/plantdisease/host-disease/boxwood-buxus-spp-phytophthora-root-crown-rot

When you make a match, look at the Cultural Control section to see what you can do about it.

Happy puzzle solving,



Hi again Anna Marie and yes, those are better pictures. I can definitely see stippling of the leaves and some webbing of spider mites. These mites are common in the Willamette Valley and thrive in hot weather. The first step in control will be to wash the plants with a strong stream of water, knocking them off if possible. Cut out the dead branches and you are ready for chemical control. The following chemicals are available for home use:
acephate
azadirachtin O
esfenvalerate
fluvalinate
horticultural oils O
imidacloprid S
insecticidal soap O
kaolin clay O
malathion
pyrethrins
pyrethroids P
spinosad O
sulfur O
thiamethoxam S

The O means they are organic, the S means it works on the whole system of the plant and the P means it is a broad spectrum insecticide that will kill many different insects. Stick with the O if possible and find a miticide in the garden section containing on of these ingredients.

I am also concerned with the bit of compost or soil around the base of one of the plants in the picture. Mites are also encouraged by too much nitrogen, either in compost or fertilizer. Make sure you are adding nothing to the soil around the plants. It might even be good to rake up fallen leaves and debris at the base of the plants for sanitation reasons.
https://pnwhandbooks.org/insect/hort/landscape/hosts-pests-landscape-plants/boxwood-buxus-boxwood-spider-mite

Good luck and thanks for sticking with this!

Thank-you!!!
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