118 MISC. PUBLICATION 43 4, U. S. DEPARTMENT OF AGRICULTURE 



Much the best policy is to follow nursery practices — mainly proper 

 watering, correct density of sowing, and use of appropriate age 

 classes — which will assure the maximum production of trees in the 

 premium grades. 



The grading standards, of course, apply to seedlings to be planted 

 in climatic conditions such as occur between the 97th and 102d 

 meridians. To make a general rule, one could say that at the eastern 

 edge of the plains, because of more favorable moisture conditions, it 

 would be safe to plant some of the smaller stock of the marginal grade ; 

 while in the drier sections, especially in the western half of the plains, 

 only the larger, sturdier, and better-balanced trees of the premium 

 grades should be planted. 



Table 25. — Classification of nursery stock on the basis of field survival 

 in a drought year 



Premium grades Marginal grades 



Species 



Osageorange 



Honeylocust 



Green ash 



Soapberry 



Black locust 



Texas walnut 



Hackberry 



American elm 



Russian mulberry___ 



Desertwillow 



Chinese elm 



Silver maple 



Catalpa 



Wilding cottonwood . 



Mini- 

 mum 

 caliper 



Inch 



Mini- 

 mum 

 green 

 weight 



Caliper 



Green 



weight 



Ounce 

 0.4 

 .4 

 .4 

 .4 

 .5 



.5 



.5 

 .5 

 .5 

 .8 

 .5 

 .5 

 .6 



Inch 

 H2-K2 



3 32-" '32 



4 32-^2 

 4 /$2- 5 $2 

 \*?,2- h< &2 

 ■^52-^2 

 ^2-^2 



M2~%2 



5 /i2- 6 /i2 



H2-H2 



Ounce 

 0. 2 -0. 4 

 .2 - .4 

 .2 - .4 

 .2 - .4 

 .2 - .5 

 .2 - .5 

 .2 - .5 

 .2 - .5 

 . 25- . 5 

 .2 - .5 

 . 25- . 8 

 .25- .5 

 .25- .5 

 .3 - .6 



Culls 



Maxi- 

 mum 

 caliper 



Inch 



Maxi- 

 mum 

 green 

 weight 



Ounce 

 0.2 



.2 



.2 



.2 



.2 



.2 



. 2 



.2 



.25 



.2 



.25 



.25 



.25 



.3 



Maxi- 

 mum 

 height 



Inches 



1 The upper limit for caliper in all species in the premium grades can be set at 12 -32 inch. Trees above 

 that caliper show good survival but are so large as to reduce planting speed materially. 



In all cases, trees which are classed as culls should be discarded. 

 It is considered extremely poor policy to use the cull grade in field 

 planting, no matter how urgent the need is for stock. It is also con- 

 sidered poor policy to transplant cull stock for an additional year in 

 the nursery, if the stock represents the poorest 10 or 20 percent of a 

 block of seedlings which was produced under favorable growing con- 

 ditions and which had germinated uniformly. Such stock includes 

 most of the seedlings which are defective from a hereditary viewpoint, 

 and these weaklings will probably succumb shortly after being field 

 planted. On the other hand, if a high percentage of the trees in the 

 block are undersized because of shortage of moisture or natural slow 

 growth rate, the seedlings can be left for another year in the nursery. 

 An alternative would be to undercut the seedlings in the tree rows, 

 pull the plantable stock, and leave the rest in place to grow into the 

 2-0 age class. 



WINTER STORAGE AND SHIPPING OF NURSERY STOCK 



Fall-dug nursery stock which is not immediately planted must be 

 stored over winter to hold it in readiness for spring planting. The two 

 methods of storage commonly used are inside storage and heel-in or 

 outside storage. The Forest Service has found heel-in storage to be 



