Although most of the Americans facing the hedgerow and marshy terrain of the Cotentin were aware of the difficulties to come, the opposite had been true before the invasion. American officers for the most part had known little of the hedgerow country. Few had seen the hedgerows, and air photos gave no real appreciation of what they were like. If most American commanders had not been able to visualize hedgerow fighting, most of the soldiers had not even been able to imagine a hedgerow. Not until the U.S. troops entered the hedgerows in June had they begun to have an idea of how effectively the terrain could be used for defense.
The hedgerow fighting in June had been so difficult that many units made special studies of the problem. Most concluded that the principles of tactics taught at The Infantry School at Fort Benning, Georgia, applied in this terrain as elsewhere. The task was to pin the enemy down with a base of fire and maneuver an element along a covered approach to assault from the flank. In Normandy the lateral hedgerows marked not only the successive lines of advance and the positions for a base of fire but also the enemy defensive positions; hedges parallel to the line of advance could be made to serve as covered approach routes.
As this technique developed in June, a refinement emerged. The tank-infantry team operating toward a short objective and with a simple plan proved to be effective. The objective was always the same, the next hedgerow. The plan was to provide for simultaneous advance of armor and infantry and their mutual support. As it usually worked out, a tank platoon supporting an infantry company fired through the lateral hedge that marked the line of departure and sprayed the flank hedgerows and the far side of the field to be taken with covering fire. The infantry advanced along the flank hedges to the next lateral row and cleared the enemy out at close range. With the field thus secured, one section of tanks moved forward, while the other remained temporarily at the rear to eliminate enemy troops that might suddenly appear from a concealed point or from an adjacent field. White phosphorus shells from 4.2-inch chemical mortars and artillery could be brought to bear on stubborn enemy groups. Advancing from one field to the next and clearing out individual hedgerows was a costly and slow procedure. It exhausted the troops and brought a high rate of casualties, but the slow plodding technique seemed necessary since "blitz action by tanks" was usually unsuccessful. A rapid armored advance generally resulted in only bypassing enemy groups that held up the infantry that was following.
Several drawbacks complicated the simple type of small unit attack developed in June. One difficulty was moving armor through the hedgerows. The openings that already existed in the enclosures for wagons and cattle were well covered by German antitank gunners, and the appearance of an American tank prompted an immediate reaction. Although it was possible for a tank to climb the smaller hedgerow banks, the tank's most vulnerable part, the relatively lightly armored underbelly, was thus exposed. Consequently, before a tank could protrude its guns and advance through a hedgerow, it was necessary for accompanying engineers to blast a hole through the hedgerow wall and open a passage for the tank. The explosion immediately attracted German attention to the point where armor was to breach the hedgerow, and enemy antitank weapons were not slow in covering the new opening.
The old sunken roads between the hedgerows were another hazard. So deep that they screened men and light vehicles from observation, these lanes, one observer said, "might have been made for ambush." The highways of the region, narrow tarred roads, were adequate for mechanized forces, but the hedgerows that lined them gave excellent concealment to hostile troops.
The fields were so small and the hedgerows consequently so numerous that the opposing forces fought at close range. U.S. troops armed with the M1 rifle, a weapon more effective at long ranges, were somewhat at a disadvantage. Submachine guns, more useful for clearing hedgerows at short ranges, and rifle-grenade launchers, particularly suitable for firing over the hedges at short distances, were in too short supply to be made available to all troops. There was also a shortage of white phosphorus shells, effective in clearing hedgerow corners of enemy strongpoints.
A serious hindrance to American operations in hedgerow country was the lack of observation posts in the flat area of irregularly shaped fields, where it was impossible to anticipate the pattern of the hedgerow enclosures. Hedgerows and fields all resembled each other. There were few terrain features to serve as general objectives, as geographical markers, or as guiding points for small units. Consequently, small units had difficulty identifying their map locations with accuracy. Directional confusion often existed. Constant surveillance and frequent regrouping were necessary to maintain correct orientation.
Because the Germans occupied superior terrain in the surrounding bocage, American offensive movement brought immediate enemy artillery and mortar fire, deadly fire that had been carefully registered in advance. American counter-battery fire was difficult, for the hedgerows limited observation and prevented accurate adjustment of fire from the ground. Scaling ladders were in demand to place observers in trees, but forward observers were loath to climb trees for vantage points because of the danger of being shot by nervous Americans (many Americans were not yet experienced in battle and tended to be over-alert to the possibility of enemy snipers). So extreme had this situation become in June that one division forbade its troops in the rear of the assault elements to fire into trees unless a hostile act had been committed; the division recommended that forward observers place red streamers in the foliage and a guard at the base of any tree they used for observation purposes. Small cub planes, organic equipment of artillery units, were excellent for reconnaissance, observation, and adjustment of artillery fire, but rain and overcast skies frequently kept them grounded in the Cotentin.
Another complication was the general absence in combat units of smooth-working tank-infantry-engineer-artillery teams. Pre-invasion training had not developed such teams, and instructions during combat, however exact, could not produce proficient units in short order.
The most obvious weakness of the American ground attack during June was the tank-infantry team. Many infantry commanders did not know how to use tanks properly in support, and many tank commanders did not realize how best to render assistance in a given situation. "The development of operational procedures and techniques between the infantry and close support tanks must not be left until the arrival in the combat zone," an army report stated, but that was the situation exactly. The infantry divisions had not had sufficient training with separate tank battalions, even though the latter units were normally division attachments. To remedy this situation, a tank battalion attached to a division in Normandy continued, insofar as possible, to be associated with that division throughout the campaign. Eventually, this developed mutual confidence and an awareness on the part of both of the individual peculiarities, the limitations, and the strengths of each. By the beginning of July, sufficient time had not elapsed to produce smoothly functioning tank-infantry teams.
The greatest problem in achieving adequate tank-infantry co-ordination was that of communication. The difficulty of on-the-spot co-ordination between an infantry platoon leader taking cover in a ditch and a commander buttoned up in his tank was a continual complaint that plagued the operations of tank-infantry teams, a universal problem not limited to Normandy. Because voice command could not always be heard above the sounds of battle and the noises of tank motors, hand signals had to be worked out and smoke signals and pyrotechnic devices prearranged. Riflemen guiding tanks sometimes had to get in front and jump up and down to get the attention of a driver. Eventually a tanker would stick his head through a turret hatch and take the message. Because armor and infantry radios operated on different channels, division signal companies in Normandy installed in the tanks infantry-type radios that could be tuned to the infantry radio net. To avoid the frustration that sometimes compelled infantrymen to pound their fists on tanks in vain efforts to claim the attention of tankers peering through tiny slits, Signal companies attached to the outside of tanks microphones or telephones connected with the tank intercommunication system. Nevertheless, the development of smoothly functioning combinations had to attend the evolution through combat of elements accustomed to working in unison in mutual confidence and with a minimum of overt direction.
While infantry platoons trained with tanks as much as possible in Normandy, engineers made up explosive charges to blast tank-sized openings in hedgerows. Engineers in those divisions facing water obstacles assembled sections of bridging for future river and canal crossings. Above all, commanders tried to indoctrinate the individual soldier with the idea that continuous and aggressive advance was the best assurance of safety in the hedgerow terrain.
At the beginning of July, those Americans who had fought in the hedgerow country during the preceding month had no illusions about instituting a major drive through that type of terrain. Added to the difficulties of the terrain was the weather. In June clammy cold rain had kept the swamps flooded, slowed road traffic, neutralized Allied air superiority, concealed enemy movements and dispositions, and left the individual soldier wet, muddy, and dispirited. During the first weeks of July almost incessant rain was to continue.
In addition to problems of terrain and weather, Americans were facing a meticulous and thorough enemy, troops well dug in and well camouflaged, soldiers holding excellent defensive positions. Bolstering the defenses were tanks superior in protective armor and in fire power to those available to the Americans.