On the day following the appearance in July, 1999, of a crop formation in a field of wheat below the Cherhill Monument in Wiltshire, a small cluster of discoloured and bent stems was found in a glyph close to the formation. Samples were taken for examination.

The first point to observe is that the affected plants were highly localized. They were exclusively found in a small feature adjacent to the main formation. See the formation page for details. Within this feature, there was a small circular cluster of standing stems - about 30 in all - located at the centre of a circle. This was the only cluster of stems in the whole formation. The affected plants were found distributed around the periphery of this cluster. Only about 12 plants exhibited this malformation.

A close in situ examination of the plants produced the following observations:

• Each plant was affected near the apex of its stem. However, in some cases, the damaged region stopped short of the base of the seed head leaving a short length of unaffected stem. An example can be seen in fig 2.

• The length of affected stems varied between 23 and 26mm. 

• In every case, the lower boundary of the affected area was angled downwards away from the centre of the cluster of stems. Fig 1 shows a clear example. The rest of the cluster was to the right.

• The discoloration indicated degeneration of the chlorophyll.

• There was a variation in the degree to which different plants were affected. However, although some plants retained traces of chlorophyll, degeneration continued rapidly during the hours following their discovery until none remained.

• In every case, the upper and lower edge of the affected area was clearly defined with a uniform lack of chlorophyll to a boundary marked by a narrow dark green line. Even when, in some cases, the damaged area extended up to the first glume, this line was still visible.

• Apart from the areas described, the rest of the plants showed no signs of damage.