1. Grate the horseradish root to equal ½ teaspoon and set aside. Place the remaining horseradish root in a stockpot. Add water to cover and salt, and bring to a boil over high high. Reduce heat to medium-low, and simmer until the horseradish is tender and a paring knife can be inserted easily into root, 15 to 20 minutes. Drain and let stand 5 minutes. Dice into small pieces.
2. In a medium bowl, combine diced horseradish, apples, mayonnaise, vinegar, mustard, worcestershire, pepper, lemon zest, and grated horseradish. Pick crabmeat, removing any bits of shell. Gently fold crabmeat and chives into the horseradish mixture. Refrigerate the salad 30 minutes before serving.