I live near the coast in Maryland and would like to know the proper pruning techniques for 2 Concord grapevines. They are about 6-10 years old and do not look like any typical grapevines. The main trunk comes up from the ground about 6 inches and then has several main vines growing up. In years past I've just trained these main vines over a trellis and let them grow. This year I trimmed off all the excess vines near the top off the trellis (5 feet). What's up with my vines?
How Do I Prune a Concord Grapevine?
Here are 3 links to articles with information and diagrams showing how to prune grape vines: