Other systems of yarding have been devised, but the value of most of them has not been proved experimentally. Some system of rotation is necessary on a farm where turkeys are raised regularly. For fenced ranges where the semiconfinement method is to be used, the Minnesota plan is entirely satisfactory for small flocks. For large flocks the use of large yards in the double or triple yarding system has given good results. Under this system, after 8 or 10 weeks of brooding, the poults are put on range, which may be divided into 2 or 3 equal parts. The range used is changed yearly or biennially either by moving the equipment or by having permanent equipment for each range. In the absence of fences, turkeys may be herded so that they are protected from enemies and kept within the clean area allotted to them each season. The use of portable fences and portable roosting shelters enables the grower to move the entire flock to clean range each season or several times each season. This method is practical where large areas of suitable range are available, so that the birds can be reared each season on land that has not been used, or on which no droppings have been spread, for the preceding 2 years. In wet climates it is probably safer to allow a rest of 3 or 4 years. Enough range should be provided so that plenty of growing green feed is available in each yard at all times during the season. When the same ground is used for a whole season, and rainfall or irrigation is adequate, an acre of grass pasture should provide range and green feed for about 100 growing turkeys. An acre of alfalfa or clover would probably provide feed for 150 birds, under favorable conditions. In arid or semiarid sections, during very dry seasons, it may be advisable to provide fresh, green feed, or legume hay in abundance to discourage the turkeys from eating undesirable green feed on the range. A complete ration must be provided for such conditions. Where the range is limited to small areas of fenced land, the use of a number of permanent range houses set in a row, preferably 200 feet or more apart, in the middle of the range and along the dividing fence is a practical method of range utilization. The dividing fence should be double so as to provide a neutral area between the two ranges. Under this plan the birds can use one-half of the range for 2 years in succession and the other half for 2 years without the buildings being moved. If individual range lots are desired for each flock of birds, permanent range shelters arranged on either side of a service lane, each with double or triple yards, are a solution to the clean-range problem. If double yards are used for each house or if the range as a whole is divided into 2 sections, a rotation of 2 seasons of use, followed by 2 seasons of rest may be the best plan. Where 3 yards for each house can be arranged or where the whole range is divided into 3 large yards, each yard can be used for 1 season and allowed 2 seasons of rest.