Celeriac Potato Salad

Peel celeriac; cut in half, then slice crosswise ¼” thick. Peel potatoes and cut into quarters. Place celeriac and potatoes in large saucepan and cover with water. Add 1 tsp salt. Bring to a boil; cook over low heat until tender, but not mushy, 12-15 minutes. Drain and cool. Slice potato quarters into ¼” thick slices; cut slices of celeriac into wedges (about 1” wide at the back). Cut bottoms off of artichokes (keep leaves to add to a salad, if desired). Lightly mix celeriac, potatoes, artichoke bottoms and celery in a mixing bowl. Thin mayonnaise with light cream. Add capers, parsley and tarragon; stir. Add seasoned mayonnaise to vegetables, add white wine vinegar and ½ tsp salt; stir carefully, until well coated. Chill and serve.