Westonbirt, The National Arboretum is managed by the Forestry Commission. Westonbirt Arboretum is located near the historic market town of Tetbury in Gloucestershire, England, and is perhaps the most important and widely known arboretum in the United Kingdom.
Planted in the heyday of Victorian plant hunting in the mid-19th century, today Westonbirt Arboretum is one of the finest tree collections in the world, carefully laid out within a beautiful Grade One listed historic landscape.
The arboretum is managed by the Forestry Commission, which also manages Bedgebury Pinetum. Westonbirt Arboretum is supported by the Friends of Westonbirt Arboretum charity. There has been evidence of coppicing at the site from 1292. First use of the name "Weston Birt" was in 1309. This was taken from Weston, a settlement to the west of Bowldown Road, and Birt from then lords of the manor, the Bret family.
The arboretum was established in 1829 by Robert Stayner Holford and was later extended by his son George Lindsay Holford. After the death of George in 1926, ownership of the arboretum passed to his nephew the fourth Earl of Morley, and eventually to the Forestry Commission in 1956. The Holford family's mansion Westonbirt House, became a girls' boarding school in 1927 when it was separated from the arboretum. Westonbirt Arboretum backs onto the Highgrove Estate of Prince Charles, the Prince of Wales.
Westonbirt Arboretum comprises some 18,000 trees and shrubs, over an area of approximately 600 acres (2.4 km²). Its 17 miles (27 km) of marked paths are popular with visitors, and provide access to a wide variety of rare plants. There are two main areas to explore. The Old Arboretum is a carefully designed landscape offering beautiful vistas, stately avenues, and a host of rare and exotic trees from across the globe dating back to the 1850s. Silk Wood is a very different experience. Although it also contains many exotic plantings, at its heart is a traditional working woodland, dating back to the 13th century. Dogs are welcome in Silk Wood but not allowed in The Old Arboretum.
Throughout the arboretum, each specimen tree is labeled, either on the trunk or one of the low-hanging branches. Blue labels indicate Westonbirt's "champion trees", the tallest or largest of their kind in Britain. Currently (2011) there are 79 "champions". More locations and details can be found on the Westonbirt Interactive Map.
From 2003-05 the arboretum hosted Britain's first designer led garden festival: Westonbirt Festival of the Garden.
In 2011, Treefest was launched. Following several successful years of the Festival of the Tree event, Westonbirt Arboretum refreshed the popular August bank holiday event with camping, music and more activities celebrating trees and nature. 
Christmas and the spectacle of bare, sculpted trees in winter is celebrated at the Enchanted Christmas event. From the end of November and throughout December, an evening illuminated trail runs throughout the Old Arboretum, highlighting the beauty of Westonbirt's trees in winter.
-  Westonbirt Arboretum - Forestry Commission
- "Westonbirt's timeline". Forestry Commission. Retrieved October 25, 2011.
1292 - earliest evidence for coppicing Silk Wood; 1309 - first recorded use of name Weston Birt – Weston derived from location of settlement west of Roman Bowldown Road, Birt from the Bret family, then lords of the manor
-  Westonbirt Festival of the Garden
-  Treefest
|Wikimedia Commons has media related to Westonbirt Arboretum.|
- Enchanted Christmas at Westonbirt Arboretum
- Westonbirt Arboretum - Forestry Commission
- Forestry Commission
- Friends of Westonbirt Arboretum
- The Westonbirt map - interactive map with ability to search for and highlight particular species
- Images and some highlights of Westonbirt Arboretum
- Westonbirt Interactive Map[dead link]