Woodpeckers dine mostly on insects, but will also eat acorns, nuts, fruit, sap, berries, pine seeds and suet. Offering suet in your backyard is the best enticement to attract woodpeckers. Woodpeckers will come to your backyard feeder if you have plenty of perching space and offer their favorite food: black oil sunflower seed. Select a platform feeder or seed feeder with lots of perching space. Some woodpeckers will be attracted to cracked corn or grapes, raisins and apples on a platform feeder.