Joe Sharman
Very little of Cottenham's original flora survives. A variety of plantlife would have been substantially arranged around the area's geology.
The most dramatic changes have all been due to the effects of peoples' use of the land - including over the centuries drainage, peat digging, tree clearance, creation of pasture and meadow, settlement, cultivation and application of fertilisers and chemicals.
The Ampthill and Kimmeridge clays run along west of the parish. Originally slightly alkaline, cultivation has created a poor, neutral surface soil. The peninsula (or ridge as it is now) is where the Lower Greensand overlies a harder surface layer of the Kimmeridge clay. The Lower Greensand (known locally as the redland) produces an acid soil. Where more intensive agriculture has 'improved' the soil through the addition of lime then it has become neutral but with a tendency to become more acid with time. In the village where no lime has been applied then acid loving plants such as rhododendrons can grow and can still be seen in gardens on Rampton Road.
Wells can be dug in this soil but not in the clay soils. The soil has a reputation for being hungry and it is said that if you leave your coat on the ground overnight it will be gone by the morning. A series of springs runs westward from the ridge down to the fen. To the east the soil is derived from the gault clay and produces a very sticky, slightly alkaline soil. In the north of the parish there are large gravel deposits from former courses of the river Cam. The peat which used to cover the west, north west, north and north east has all gone.