For animals that eat silage, a bale wrapper may be used to seal a round bale completely and trigger the fermentation process. It is a technique used as a money-saving process by producers who do not have access to a silo, and for producing silage that is transported to other locations. However, a silo is still a preferred method for making silage. In very damp climates, it is a legitimate alternative to drying hay completely and when processed properly, the natural fermentation process prevents mold and rot. Round bale silage is also sometimes called `haylage`, and is seen more commonly in Europe than in either the USA or Australia. However, hay stored in this fashion must remain completely sealed in plastic, as any holes or tears can stop the preservation properties of fermentation and lead to spoilage.