An area of regular post-medieval drainage ditches is visible on aerial photographs on moorland. They are similar to those cut as part of the Knight family's attempt at improvement and may show an attempt to copy the Knight family techniques.

An area of regular post-medieval drainage ditches is visible on aerial photographs on moorland at South Regis Common, Challacombe. Centred at approximately SS 7115 4039, the ditches run northwest to southeast, covering an area of approximately 1 hectare and are similar to those cut as part of the Knight family's attempt at improvement. According to Orwin, many miles of drainage ditches were cut across parts of Exmoor, but failed to provide adequate drainage for the land to be enclosed. These drains lie outside the former Royal Forest, suggesting that they may have been cut in an attempt to copy the Knight family techniques. They are not depicted on the 1st Edition Ordnance Survey map, suggesting they may have been constructed after publication in 1890. [1-4]