Camouflage consists of two elements: concealment and deceit. The two components of concealment are screening (i.e. hiding defence works from view with natural screens or artificial screens) and blending (i.e. blending defence works into the background). The two main components of deceit are disguise (to give the enemy a false impression of the defence work) and dummy positions (to deceive the enemy of the true tactical situation).
Every military operation leaves its own trace on the ground which the enemy would be trained to recognise. Defence works could be betrayed by shadow, shine and tracks leading up to them. Camouflage was the art to prevent drawing the enemy observer’s attention.
Above images show the trace left on the ground of a platoon postion and Field battery. Also a pillbox, huts and trucks are betrayed by shine. A track leads
straight to a machine gun post.
The type of materials used would depend the background and the distance and angle of expected enemy observation. All camouflage materials are chosen for their ability to match the background against which they will be used.
Camouflage materials consist of:
Materials of every day life – branches, turf, debris of all sorts, scrap building materials etc
Materials available from Army sources but not specifically manufactured for camouflage e.g. paint
Materials available from Army sources and manufactured specifically for camouflage
Camouflage materials for all purposes
Nets - an open mesh fish –net. Usually recommended for mobile equipment as it was easily rolled up and transported. Typically issued in rolls of 35 ft by 35 ft; 24 ft by 24 ft and 35 ft by 17 ft.
Galvanised wire netting – recommended for permanent work. Typically issued in rolls of 36 in or 48 in wide and 50 yards long with varying mesh (general purpose mesh was 1 ½ inches). Both nets and galvanised wire netting were both merely the foundation on which the concealment material (coloured scrim garnish) was added.
Garnish – hessian strip issued in rolls 2 in. wide and 100 yards long in four colours (dark green, light green, light earth and brown). It was added to nets and galvanised wire netting.
Shrimp net – a knotted or woven mesh, coloured with a pattern of brown and green. Part of an armoured fighting vehicles unit equipment. Issued in rolls of 25 ft by 12 ft and 35 ft by 15 ft with either a knotted mesh of 1 cm or woven mesh of 0.5 cm.
Coir netting – a fine mesh useful for ground covering as it was virtually rot proof. Issued in rolls or sheets with a mesh of 3/8 or ½ inch.
Hessian sheets – coloured either earth or dull green and useful for ground covering. Typically issued in sheets of 6 ft by 12 ft and 12 ft by 20 ft.
Steel Wool – mounted on a galvanised wire netting and was issued in either fine or coarse quality in either grass green or earth colour. It was used to represent grass, plough or trodden earth.
Nets would be supported on a frame consisting of steel wire and poles (for example tubular steel poles, ash crooks or Hop poles).
Above: Left - two methods of supporting netting. Right - Garnish added to netting.
Defence works were often obvious on aerial photographs due to tracks leading up to them. This could be avoided to some extent by careful planning of tracks (e.g. to follow hedges, edges of woods) or if this was not possible by giving the track a non-military purpose by linking it to other roads or group of buildings etc. Lt Col Birchall, General Staff 55th Div, issued a memo on camouflage on Aug 25th 1940 and notes many cases of bad track disciple, especially on those works completed by contractors. Steel wool was to be used to help hide the worst cases until the grass grew back. The method of extending the track beyond its true terminus was also to be adhered to. Mention is also made in other War Diaries that work on defence post should not continue in snow. Exercises in manning posts were also not to be carried out in snow.
Camouflage - MTP No 46 Part 1: General Principles, WO, 1941
Manual of Field Engineering Vol II (R.E), HMSO, 1936
55th Div papers, TNA