In a small bowl, whisk the salt and vinegar until the salt mostly dissolves. Whisk in the maple syrup and the olive oil. Season with freshly ground pepper.
In a small skillet over medium high heat, using a wooden spoon, constantly stir the pecans, maple syrup, and coconut oil until the nuts are toasted and the maple syrup coats the nuts. Transfer to a bowl.
Very thinly slice the salad turnips. (Use a mandoline if you have one.) Toss with the dressing and set aside.
Tear the lettuce into bite-size pieces and arrange in a serving bowl or plate. Scatter the salad turnips and avocado on top. Coarsely chop the pecans and sprinkle over the salad. Drizzle with more vinaigrette and generous grinds of black pepper.
Toss the salad at the table before serving.
If you don’t have Japanese “salad” turnips, substitute radishes.