Muscadine pruning advice
Pruning Muscadines
The Muscadine has a boundless enthusiasm for growth, and you must restrain it or you will soon have jungle of vines. Therefore just as soon as you can, establish a main trunk for the vine. Tie this to the post and cut it off when it reaches the top. The trunk then may be allowed to develop about eight arms near the top. These should radiate outward like the spokes of a wagon wheel. To support them properly, wires should be stretched between the posts, thus forming a canopy. The main arms of the Muscadines do not produce fruiting shoots. One-year-old canes growing from these arms are pruned back to provide fruiting shoots. To prune properly, cut back the previous season's side growth, allowing about six buds to remain on the canes. Each year for best results, cut out one of the main arms. Then select a shoot near the top of the trunk to replace it. If this is done faithfully you will renew all of the arms every eight years. If you don't do this, the old arms in time will become so heavily spurred that their fruiting vigor will be reduced.
Pruning (all grapes)
Grapevines require drastic annual pruning, undertaken in late winter or early spring. The many pruning systems can not be described here, but essentially they boil down to two: cane pruning and
spur pruning. The point to remember is that grapes are borne exclusively on "one-year wood," the woody canes which were the green shoots of the previous season. The wood of some varieties yields most heavily from the 3 or 4 buds closest to the trunk; so these are pruned by cutting back several canes to "spurs" of 3 or 4 buds and trimming off everything else. The spurs yield sufficient crop. The canes of other varieties bear best from the 4th to the 10th buds, counting out from the trunk; so these are pruned by cutting back several canes to leave 8 to 10 buds each according to the vigor of the vine and counting from the trunk, then trimming off everything else and tying these & "bearing canes"; to the trellis. In cane pruning, 2 short spurs are also left well placed near the head of the vine, not for crop but to provide well placed & "one year wood" for the following year.How many buds to leave on mature varieties. Amount left can vary with vigor of vine.<a this. like look may Concord A pruned. this Blanc Villard>
http://ediblelandscaping.com/careguide/Grape/