Thornton Forestry is dedicated to the ongoing stewardship of trees throughout Thornton. The links found on this page provide information on how to properly maintain and care for your newly planted and established trees in Colorado’s Front Range. Open all Forestry Information Mulching [PDF/182KB]Pests & Disease [PDF/338KB]Planting [PDF/1.7MB]Pruning [PDF/542KB]Tree Watering [PDF/706KB] Recommended Plants and Trees Annuals [PDF/644KB]Grasses [PDF/512KB]Perennials [PDF/547KB]Shrubs [PDF/2MB]Trees [PDF/827KB] Emerald Ash Borer Information Colorado State Forest Service EAB Quick GuideManaging EAB Decision GuideInsecticides Used to Control Emerald Ash Borer on Residential Shade Trees-CSU Tree Planting and Recommendations Front Range Tree Recommendations Arbor Day Tree Sale Thornton Forestry will sell 1-inch-caliper trees weighing about 20 pounds, making them easy to transport.Saturday, April 24Carpenter Recreation Center8 a.m. - 2 p.m. (or until sold out.) Trees sold are available on a first-come, first-served basis. No reservations.Cost is $50 per tree payable by check or credit card only. Additional Resources Find an Arborist and Homeowner Tree Care InfoCity's Annual Flower BedsISANorthern WaterPlant Select