Rosaceae, the rose family, is a varied group of plants: they may be trees, shrubs or herbs, usually producing stout stems, woody at the base, armed with prickles. Leaves are compound (pinnate or palmate) or simple, often with stipules at the attachment point. Flowers are radially symmetric, formed of five sepals and five, unfused, generally non-overlapping petals. Often the sepals are visible from above through the gaps between the petals, being displaced by 36 degrees. At the flower center are many stamens, and one to many pistils. There are over 900 rosaceae species in the US, in 66 genera. Many produce edible fruits.