Denison Landscaping and Zipper Sales partner up to show leadership and corporate responsbility by adopting “Green” technology pro-actively and not due to mandates. By investing in technology Denison is helping not only the company but leading the landscape industry with implementation of alternative fueled mowers. Presently we have 13 various styles of Propane mowers in use while being environmentally friendly they are also more economical to use and maintain. GO GREEN!