Preparing seedbeds; furnishing, placing, and covering limestone, fertilizer, and seed; compacting seedbeds; furnishing, placing, and securing mulch; mowing; and other operations necessary for the permanent establishment of grasses and legumes from seed on shoulders, slopes, ditches, or other roadside areas; all in accordance with these specifications. Seeding and mulching shall be performed on all earth areas disturbed by construction and on portions of areas seeded under previous contracts where in the opinion of the Engineer there is unsatisfactory vegetative cover. The Contractor shall adapt his operations to variations in weather or soil conditions as necessary for the successful establishment and growth of the grasses or legumes. In all operations covered by this section, care shall be taken to preserve the required line, grade, and cross section of the area treated.