Help - we have planted [last November] 100 Smaragd cedar trees. This summer we noticed a bronzing followed by the dying of the tips of the branches. I have been able to determine [internet reseach] that they are infested with spider mite. The only advice I can find is to forcefully spray the trees twice a week until the rains begin. Which I have been doing. Will the trees recover? Can I do anything else?
There is probably a pesticide available that is appropriate, if you would prefer to take that additional step. Make sure mites are your problem (and this is the right time of year to make applications) and inquire at a nearby, trusted independent garden center about suitable product(s). Be sure to read and follow label directions.