Subd. 1. Residential Districts. In Residential Districts all materials and equipment shall be stored within a building or fully screened so as not to be visible from adjoining properties, except for the following: laundry drying, recreational equipment, construction/landscaping materials and equipment currently (within a period of thirty-six (36) hours) being used on the premises, agricultural equipment and materials if these are to be used or intended for use on the premises, off street parking of passenger automobiles and pickup trucks, boats and non-commercial, personal, recreational travel trailers are permissible if stored in the rear yard.