Cornwall’s rivers and estuaries meander across much of the county, often arising high on the moorland spine of Cornwall as fast and bubbling streams before taking their leisurely path to the sea, passing farmland, towns and villages on their way. The valleys are often quiet havens for wildlife, supporting reedbeds, wet willow carr, marshes, ancient woodlands, saltmarshes and mudflats.

The north coast estuaries include the Camel, Gannel and Hayle rivers with ever-changing sand banks and channels at their mouths. On the south coast, the gentler cliffs are punctuated by the deep estuaries or drowned river valleys of the Fal, Helford, Fowey and Tamar rivers, many of which have been designated as candidate Special Areas of Conservation for the estuarine wildlife they support.

The larger rivers have varied and extensive catchments which can pose challenges to the water quality and wildlife they support.

Landscape, Trees and Invasive Plants

Cornwall’s landscape is of national and international importance as well as being vitally important to the local economy. Twenty-seven per cent of the County is designated an Area of Outstanding Natural Beauty (AONB) and a further 24% as Area of Great Landscape Value (AGLV). The landscape is formed from a combination of climate, geology, natural features and human activity.

Although a relatively poorly wooded county (7.5% compared with the national average of 8.4%) trees and woodlands are an important component of the landscape. Whether they be ancient estuarine oak woodlands, the windswept hedgerow trees lining our winding country lanes or the specimen trees in our parks and gardens, all trees and woodlands help define our sense of place as well as supporting a wide range of species.

Other important features of the Cornish landscape are the Cornish hedges that divide the fields, and line our lanes and roads, and the traditional orchards. Many hedges are of great antiquity and wildlife value with their great variety often defining a location. In recent years, there has been renewed interest in the management of traditional orchards as well as the conservation of our old local fruit varieties.

Cornwall's landscape is highly managed and some practices or changes in management regimes have had unfortunate side effects. Our increased interest in gardening and exotic plants over the last 200 years has led to a great number of introduced species and cultivars. Many have made Cornish gardens the envy of the world, however, some have made themselves at home and have become highly invasive, spreading over the garden hedge and into the countryside, displacing our natural flora. Cornwall is currently pioneering work in the control of invasive alien weeds such as Japanese knotweed where a top scientific research company has been contracted to examine the weed and potential natural control methods. There are also a few problem native invasive weeds such as common Ragwort which require careful and co-ordinated management to limit its spread.