I thought maybe spider mite too. Look very very closely at the crooks and crannies were the webs are. You are looking for tiny red bugs in the spider webs. I doubt a blast of the hose will get rid of the spider mites for long. I would use a systemic on the roses and Japanese Maple. Make sure there are no flowers on the roses or you will kill the bees too.
Yes, your mystery red bush is a Acer palmatum (Japanese Maple). There are literally thousands of cultivars so narrowing it down to an exact one will be difficult. You can call it a "dwarf threadleaf Japanese Maple".
Pay attention to the watering suggestions from NMoasis.
