1 Selection of breeding varieties of free-range chickens The selection of chicken varieties should be determined according to the adaptability and market demand of forest chickens. Generally, local thoroughbred chickens with strong adaptability, disease resistance, strong foraging ability, roughage tolerance, tender meat and delicious taste or hybrid chickens with local blood origin of more than 75%, such as Snow Mountain Chicken, Yanfu Chicken and Yangkou Chicken, are selected. 2 Free-range chicken farms should be located far away from livestock and poultry trading places, livestock and poultry slaughterhouses, processing plants, chemical plants and garbage disposal sites to avoid air, dust, water, germs, noise and other pollution. Choose a grassy hill and grassy slope with the lee facing the sun, flat terrain and no stagnant water. There should be trees or orchards next to it, and the shade of trees should be above 70%, which is convenient for chickens to enjoy the cool in the shade when the sun is strong and prevent chickens from heatstroke; In addition, the photosynthesis of trees absorbs a lot of carbon dioxide and releases oxygen, which effectively reduces the influence of harmful gases such as carbon dioxide and chlorine gas emitted by chicken manure and improves the immunity of chickens, thus achieving the effect of pollution-free ecological farming with less drugs and no drug residues.