for infantry. On Rommel's order, the number of mines along the coast was tripled. The Allied air offensive over Germany had crippled the Luftwaffe and established air supremacy over western Europe, so Rommel knew he could not expect effective air support. The Luftwaffe could muster only 815 aircraft over Normandy in comparison to the Allies' 9,543. Rommel arranged for booby-trapped stakes known as Rommelspargel (Rommel's asparagus) to be installed in meadows and fields to deter airborne landings. German armaments minister Albert Speer notes in his 1969 autobiography that the German high command, concerned about the susceptibility of the airports and port facilities along the North Sea coast, held a conference on 6–8 June 1944 to discuss reinforcing defences in that area. Speer wrote: Armoured reserves Rommel believed that Germany's best chance was to stop the invasion at the shore. He requested that the mobile reserves, especially tanks, be stationed as close to the coast as possible. Rundstedt, Geyr, and other senior commanders objected. They believed that the invasion could not be stopped on the beaches. Geyr argued for a conventional doctrine: keeping the Panzer formations concentrated in a central position around Paris and Rouen and deploying them only when the main Allied beachhead had been identified. He also noted that in the Italian Campaign, the armoured units stationed near the coast had been damaged by naval bombardment. Rommel's opinion was that because of Allied air supremacy, the large-scale movement of tanks would not be possible once the invasion was under way. Hitler made the final decision, which was to leave three Panzer divisions under Geyr's command and give Rommel operational control of three more as reserves. Hitler took personal control of four divisions as strategic reserves, not to be used without his direct orders. Allied order of battle Commander, SHAEF: General Dwight D. Eisenhower Commander, 21st Army Group: General Bernard Montgomery U.S. zones Commander, First Army: Lieutenant General Omar Bradley The First Army contingent totalled approximately 73,000 men, including 15,600 from the airborne divisions. Utah Beach VII Corps, commanded by Major General J. Lawton Collins 4th Infantry Division: Major General Raymond O. Barton 82nd Airborne Division: Major General Matthew Ridgway 90th Infantry Division: Brigadier General Jay W. MacKelvie 101st Airborne Division: Major General Maxwell D. Taylor Omaha Beach V Corps, commanded by Major General Leonard T. Gerow, making up 34,250 men 1st Infantry Division: Major General Clarence R. Huebner 29th