126 MISC. PUBLICATION 4 3 4, U. S. DEPARTMENT OF AGRICULTURE 



times. This is a desirable feature, especially in Oklahoma and Texas 

 where field planting is carried on throughout most of the winter 

 months. 



When trees in heel-in beds respond in the spring to rising soil 

 temperatures and leaf out and begin growth, precautionary measures 

 are necessary to hold them dormant until planting preparations are 

 completed. The fundamentals of such procedure lie in keeping direct 

 sunlight from the beds, thereby retarding the rise of ground tempera- 

 tures. In the northern plains, stock can be held dormant in the heel- 

 in beds by covering the beds in winter with 1 or 2 feet of packed snow. 

 If the snow is then covered with a thick layer of straw, the beds 

 reserved for late spring planting will remain frozen as long as desired. 

 The snow and straw covering should be extended well out from the 

 edge of the beds, to prevent thawing out from the sides, and should be 

 put on after the frost has penetrated the ground from 3 to 6 inches. 

 In the spring, the beds will thaw out rapidly after the straw cover is 

 removed, and shipment of trees can begin at once. 



A simple adaptation of this method is to heel-in the trees on a strip 

 of ground 30 to 50 feet wide on the lee side of a 4-foot, slat-wire fence. 

 A snowdrift will form over the trees, and its melting can be retarded 

 in early spring by covering the drift with straw. Stock so retarded 

 will leaf out very rapidly after the snow melts and the straw cover is 

 removed, perhaps because of the abundant moisture from the melted 

 snow. If growth must still be retarded the stock should be moved 

 at once into a drier section of the heel-in site. 



In the southern Plains the ground seldom freezes deeper than 6 or 

 8 inches and snow is seldom available for holding seedlings dormant. 

 It is necessary to shade the beds with burlap or snow fence while the 

 trees are still dormant. It is important to remember that the main 

 purpose of the shading is to hold down soil temperatures. To 

 expedite work and aid in ventilation, the shade should be high enough 

 to allow easy working space below it. 



As a last resort, and in case the trees in heel-in beds do start leafing 

 out and it is known that they will not be planted for some time, it is 

 advisable to move them from one bed to another; this will serve to 

 check growth for some little time. 



Packing and Shipping 



Stock used in shelterbelt planting is first transported from each 

 individual nursery to heel-in beds in each planting district for over- 

 winter storage and subsequent shipment to the planting areas. In this 

 operation, bulk shipments by either trucks or rail are satisfactory. 

 Rail transportation in refrigerator cars equipped with heaters is 

 especially advantageous in the late fall or early spring to prevent 

 freezing of stock in transit. Long-distance transportation is also best 

 accomplished by rail or by large trucks if the amount of stock involved 

 will amount to a full car or van. Large van shipments have an advan- 

 tage over rail shipment since they can be loaded at the nursery and 

 unloaded at the district heel-in beds, thereby avoiding extra handling. 

 When stake-body trucks are used, they should be lined on the sides with 

 a tarp, plywood, or similar material to prevent drying out of stock. 

 Thoroughly saturated shingletow should be used liberally in packing 

 the bundles into the truck and heavy canvas tarpaulins should be 

 lashed over the top of the load. 



