My first planting experience of grape vines was in the spring of 2008 so I am a beginner. I am thinking of planting this coming spring many grape vines in a small area in my backyard and grow these like small single trunk trees with (heavy) head pruning, leaving a few grape bunches on each vine (tree) when mature. The idea is that the root system of each vine will attend to a few bunches; this compared to a vine spread wide over a single or double T-bars. The draw back I see is the fewer number of leaves for photosynthesis but then the plant will be kept pruned and small. The other point is the root competition for nutrients and moisture but then these will be shared by the root systems. Where is the real drawback of this kind of strategy?