Wis. Stat. § 812.14: Answer conclusive if no reply by plaintiff; procedure following reply.

(1) The answer of the garnishee shall be taken as true unless the plaintiff, within 20 days after the receipt of the answer of the garnishee, serves a reply upon the garnishee.

(2) Upon service of the reply, issue shall be joined between the plaintiff and garnishee, and the parties shall thereupon proceed as in ordinary civil actions.

(3) Trial of a garnishment issue shall be to the court.