Answer based on context:

In late February 1586, Friedrich Cloedt, whom Gebhard had placed in command of Neuss, and Martin Schenck went to Westphalia at the head of 500 foot and 500 horse. After plundering Vest Recklinghausen, on 1 March they captured Werl through trickery. They loaded a train of wagons with soldiers and covered them with salt. When the wagons of salt were seen outside the city gates, they were immediately admitted, salt being a valued commodity. The "salted soldiers" then over-powered the guard and captured the town. Some of the defenders escaped to the citadel, and could not be dislodged. Claude de Berlaymont, also known as Haultpenne after the name of his castle, collected his own force of 4000 and besieged Schenck and Cloedt in Werl. Attacked from the outside by Haultpenne, and from the inside by the soldiers in the citadel, Schenck and Cloedt broke out of the city with their soldiers on 3 March. Unable to break through the lines, they retreated into the city once more, but several of their soldiers did not make it into the city, and plundered the neighboring villages; 250 local residents were killed. On 8 March, Schenck and Cloedt loaded their wagons, this time with booty, took 30 magistrates as hostages, and attacked Haultpenne's force, killing about 500 of them, and losing 200 of their own. Included in the hostages were the Bürgermeister Johann von Pappen and several other high-ranking officials; although von Pappen died during the retreat, the remaining hostages were released after the payment of a high ransom. Schenck retreated to Venlo and Cloedt returned to the city of Neuss.

What did Cloedt use to capture Werl?
salt