Fort Tryon Park were planted with herbaceous plants, shrubs, and trees representing different seasons. There were also numerous small lawns including the Children's Play Lawn and the Picnic Grounds, as well as formal planted areas such as Corbin Circle, the promenade, the terrace, and the playground. The Heather and Alpine Gardens were distinctly designed with a large variety of plantings. Though it is illegal to forage for plants inside Fort Tryon Park, or at any other public park within the city, relatively few summons are written for such violations within the park. The Heather Garden, located in a ridge west of Corbin Drive and the promenade, is described by NYC Parks as "the largest public garden with unrestricted access in New York City", with an area of . It was planned by the Olmsted Brothers as a gardenesque site with American elm trees and low-growing heather, also known as Calluna vulgaris. The short height of the heather was intended to allow views of the Hudson River, and stone seating allowed visitors to observe the landscape. The heather took several years to grow to its full height. The Heather Garden became overgrown with invasive species after a remodeling in 1955 failed to take Olmsted's design into consideration. The garden was restored in the late 1980s following Olmsted's original plans. Minor additions and improvements continued to take place afterward. The garden contains perennials, shrubs, and trees, as well as plantings representing each season. The Alpine Garden, the other formal space planned by the Olmsted Brothers, is located on the ridge along the park's eastern side, to the east of the Cloisters. It contains a stone stair and a grotto. Originally planted with alpine plants, the garden later became overgrown before being restored in 2009. The garden incorporates numerous rocks, which according to NYC Parks' website " the outcroppings of metamorphic Manhattan schist". The rocks used in the garden include quartz, feldspar, mica, and garnet; some of the stone comes from excavations during the park's and subway's construction. In addition, the Cabrini Woods Nature Sanctuary runs alongside Cabrini Boulevard at the southwestern corner of the park. The woods connect to Inwood Hill Park and Fort Washington Park, the last two natural woodlands in Manhattan. Both the woods and the boulevard are named after Frances Xavier Cabrini, the first American canonized as a Roman Catholic saint. The woods serve as a habitat for wildlife,