Certified Arborist Mark Williamson, a member of the International Society of Arboriculture, offers a full line of health care and maintenance services for trees, ornamentals and shrubs to the North Texas area. We cover Dallas and areas north of Dallas such as: Highland Park University Park Farmers Branch Carrollton Addison Plano Frisco Allen McKinney Murphy Sachse Rowlett Fairview Richardson Garland Mesquite and other cities North of Dallas To find out if we service your area