NURSERY PRACTICE FOR PRAIRIE-PLAINS PLANTING 127 



When stock is to be shipped from the central storage or heel-in 

 grounds to the planting site, orders are sent in to the shipping point 

 in advance, specifying the date planting is to begin. The orders list 

 the species and amount of stock required for each individual field 

 planting. The night before the stock is to be planted, the shipping 

 force packs into crates, directly from the heel-in bed, enough trees to 

 keep all crews busy the entire day. It is desirable to mark each crate 

 with a tag showing species, age class, number of trees, and seed source, 

 in case various sources are involved. In most cases age class and seed 

 source need not be recorded on each tag if the stock in each species 

 used on a given district is all of single species and age class. The 

 crates used in shipment are of such a size as to be easily handled and 

 also to serve as seats for the planting crew. 



SEEDLING PROTECTION 



In the nursery and in the process of distribution, seedlings are more 

 susceptible to injury or loss from a variety of causes than at any 

 later time in the field. Concentration of large quantities of nursery 

 stock in heel-in beds and in storage sheds increases the probability of 

 loss. Intensive protective measures are important at these stages, 

 both because of the immediate values involved and because future 

 work plans depend upon the stock being available in specific amounts 

 at a definite time. 



It is considered good policy in growing large quantities of nursery 

 stock to allot production to several medium-sized nurseries separated 

 by some distance, rather than to concentrate all production in one 

 large nursery. Then if a localized catastrophe, such as disease, in- 

 sects, or a hailstorm, strikes a single nursery and seriously disrupts an 

 entire season of field planting planned on a minimum production 

 schedule, the blow to the planting program will be less severe than if 

 the stock were concentrated. 



Protection of seedlings involves guarding against loss by four major 

 groups of factors, meteorological, entomological, biological, and 

 pathological. The chief meteorological factors which cause loss in the 

 nursery are wind, heavy rain, heat, drought, hail, and frosts. For 

 most of these, certain measures can be taken to prevent or minimize 

 damage. 



Wind 



Wind adversely affects seedling production chiefly (1) by uncovering 

 the seed and seedlings and blowing them out of the ground, or covering 

 over or burying them; (2) by causing mechanical injury from particles 

 of sand sweeping along the ground and cutting the small seedlings 

 near the ground line, or sand blasting the tender foliage or cotyledons; 

 (3) by accelerating depletion of the soil moisture; and (4) by intensify- 

 ing the drying effect of high temperatures on the plant tissues. 



Protection from wind is most important during the germination 

 period and early life of the seedling, since this is the time when maxi- 

 mum injury occurs. On nursery sites with One-textured soils, which 

 are not protected by permanent shelterbelts, considerable benefit may 

 be obtained from the use of snow fences placed at intervals of 50 to 200 

 feet at right angles to the direction of prevailing wind. Closer spacing- 

 is needed on sandy soils. 



