Separate the head of leafy green lettuce into individual leaves. Wash and blot dry with paper toweling. Gather half the leaves together and then cut crosswise into 1 inch wide strips. Repeat with the romaine lettuce. Alternate whole leaves of the lettuce and romaine around the inside edge of a large salad bowl. Fill the center with shredded lettuce and romaine.
Cover with damp paper toweling. Refrigerate until serving time. Scrub and cut the cucumber in half lengthwise; cut crosswise into thin half-moons. Place in plastic bag and refrigerate. Combine orange juice, lemon juice, honey, mustard, orange rind and salt in small bowl. Whisk in oil until well blended. Refrigerate until ready to use. Pour about half the dressing over lettuce strips; toss to coat. Arrange cucumbers in circles in center; arrange shredded beet around cucumber. Serve with remaining dressing.