The Bartramian Audubon Society along with Seneca Rocks Audubon Society, the Department of Conservation and Natural Resources and Oil Region Alliance will host a bird and nature festival Friday through Sunday near Oil City.

Nature hikes, bird walks, workshops, speakers and an Owl Prowl are planned. Some events have been approved for Act 48 credit for educators.

For information or to register, visit www.oilregion.org or call 800-483-6264. Space is limited.

A Tribute of Song is the theme for the spring concerts to be presented by The Bach Society at 8 p.m. Friday at Center Presbyterian Church, 211 Center St., Slippery Rock, and 8 p.m. Saturday at Tower Presbyterian Church, 248 S. Broad St., Grove City. Admission is free. The Bach Society will be under the direction of David Mruk, and Kathleen Cashdollar will accompany on the piano.The concerts will be presented in loving memory of Frank Stearns, who directed the choir from 2003-08. The selections are favorite pieces of Stearns. They range from sacred and classical pieces to popular music.

MARS - Mars United Methodist Church's annual pies, posies and peddlers' market day will be held from 9 a.m. to 3 p.m. Saturday at the church, 525 Pittsburgh St.The event will feature homemade pies baked by the church ladies, plants, gift certificates and items from more than 30 vendors.For information about the market day, call Barb Sekel at 724-772-7905.Volunteers to 'Pull out the Mustard'Volunteers are invited to a Pull out the Mustard event at Moraine and McConnell's Mill state parks from 9 a.m. to noon Saturday.The goal of the event is to pull out garlic mustard from the woods to allow room for important native plants to grow.Participants should arrive dressed for the weather and are asked to take work gloves. Lunch will be provided at 12:30 p.m. at McDanel's Launch.To sign up, call Natallie Price at 724-283-5497 or nativenataliezoominternet.net. The event is sponsored by the Moraine, McConnell's Mill and Jennings Commission.

Ambridge A new exhibit, Harmony in Wood: the Furniture of the Harmony Society, will open from 9 a.m. to 5 p.m. Saturday at Old Economy Village.The Pennsylvania Historical and Museum Commission is offering free admission to the village and exhibit to coincide with the exhibit's opening. A lecture by American furniture historian and author, Philip Zimmerman, will be given at 2 p.m. in the visitor center classroom.The exhibit will be open during regular site hours, 9 a.m. to 5 p.m. Tuesday through Saturday and from noon to 5 p.m. Sundays. Admission to the site, which includes the exhibit, will be charged after May 2.For information, call 724-266-4500 or send an e-mail to ra-oldeconomystate.pa.us.