Like most agricultural land in the south of England, this area was once divided into a larger number of small fields.

Take for example the area to the north of Wheathampstead, just south of Heron's Farm.  An 1880 map of the area shows several hedge boundaries running north and south from the path that leads west towards Marshalls Heath Lane, indicating medieval strip farming from the higher ground down to the river.  The only traces of these hedgerows today are the isolated mature trees, though marks can sometimes be seen in the soil in winter when there are no crops.  The small ditch to the northwest of the path crossroads shows the line of an old field boundary.

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