At least 2 days before decorating cake, make light rose royal icing wild roses using tip 101, 102 or 103 and Flower Nail # 7. (about 80 flowers were used for this project - make additional in case of breakage); add tip 233 yellow royal icing pullout centers. Place in flower formers; allow to dry completely. Brush the centers of the dried roses with Pearl Dust.
Bake your favorite 2-layer cake recipe or mix following recipe instructions in 6 and 8 in. square pans. Cool layers in pans on wire rack 10 minutes. Remove from pan and cool completely. Stack on foil-covered cake board sized to fit.
Arrange 6-in. cake on same-sized cake board. Place 8 in. cake on foil-covered cake board, securing with icing. Spatula ice layers in ivory buttercream icing. Insert dowel rods into 8 in. layer; position 6 in. cake on 8 in. tier, placing over dowel rods.
Randomly decorate tip 32 outline chocolate buttercream icing tree trunks over cake; add smaller tip 16 branches. Randomly attach flowers singly and in groups along trunks and branches with dots of icing.