Walnut Grill is preparing to open its first restaurant outside of Pennsylvania in Ellisville, Mo., a western suburb of St. Louis, according to the St. Louis Business Journal, a sister publication of the Pittsburgh Business Times. The new restaurant is expected to open in October. Kirk Vogel, president of Walnut Gril, told the Pittsburgh Business Times in early March it was planning to open three or four restaurants in the St. Louis area in the next four years. Walnut Grill's local restaurants…
