The Park contains a regionally important area (about 130 hectares) of Acid Grassland, which is a priority habitat for conservation under the UK Biodiversity Action Plan (BAP). Despite periods of considerable disturbance, such as during World War II, the continuity of deer grazing has meant that Bushy has maintained areas of Acid Grassland for centuries. The dry, acidic, nutrient-poor soils support fine grasses and characteristic wild flowers, including: Sheep's Sorrel, Harebell, Tormentil, Heath Bedstraw and others. Wetter areas support a variety of rushes and other species, and Bushy is the only site in London with Mudwort, a real rarity.