Hey, Laurie

I think it is much more likely that you are dealing with fall webworm rather than tent caterpillar.  TC is a spring pest and pretty much limits itsellf to the prunus and malus genus'.  The fall webworms emerge in mid-to late summer and build much more open "tents".  They are also much less picky about the host trees they use.  They rarely cause much real damage because they are active late in the season after the tree has had a chance to build reserves.  Most common insecticides should work on them.  BT, neem oil and insecticidal soap are organic alternatives.  Spray only the branches affected by the webs.  They feed gregariously and will usually be in or near the webbing.  There is no need to prune the branch. There is a good chance defoliated branches will releaf next spring.