compared to transplant stock. Recently, tests of planting 1+0 seedlings have begun. 

 Nurserymen believe they can grow 1+0 ponderosa pine stock suitable for planting, 

 especially on well-prepared sites. 



Raising seedlings in inexpensive containers and then outplanting both the seedling 

 and container is a method being either tested or used successfully in several forested 

 regions (Jones 1967; Kudrj avcev 1965; Williamson 1964). Planting containers or tubes 

 of various materials, sizes, and shapes are being tested. Advantages claimed for this 

 system include minimizing production time, cost, and initial planting shock; prolonging 

 the planting season; and increasing survival on certain sites. Commonly the tubelings 

 are planted in the field 6 to 8 weeks after seed germination. At that stage of growth, 

 the roots have not reached the bottom of the container, so root growth is not inter- 

 rupted during outplanting. 



Container planting was tested in central Idaho as a means of increasing survival 

 on dry sites (Curtis and Foiles 1964). Sixteen kinds of containers, 10 to 18 inches 

 long and made of several different materials, were planted on various sites and in 

 two seasons, spring and fall. Seedlings were grown in the tubes for 1 and 2 years 

 before outplanting, rather than for 6 to 8 weeks. Relatively long containers were 

 used to minimize root competition and to provide the taproot with a better chance of 

 remaining in moist soil. Container planting did not improve survival under the con- 

 ditions tested in central Idaho. Possibly some other form of container planting will 

 prove advantageous in the future, but for the present, survival of bare-rooted stock 

 is satisfactory. 



Stock lifting and storage. — In California, date of lifting and length of time in 

 storage strongly affect the root-regenerating potential of outplanted stock (Stone 

 and Schubert 1959b). The optimum time for lifting and storing stock needs to be 

 determined for each forest nursery in the Intermountain Station territory. Usually, 

 ponderosa pine stock is lifted in early spring and stored at near- freezing temperatures 

 for periods of a few days to 8 or 10 weeks with carefully controlled humidity. This 

 schedule agrees with Stone and Schubert's recommendations from California for timing 

 the lifting and planting operations to take advantage of the period of peak root growth 

 in the spring. 



Stock shipment and field storage .--Hie best method of packing and shipping 

 nursery stock depends on weather conditions, distance, and time in transit. The 

 stock must be protected from heating within bundles and from excessive drying by sun 

 and wind. Roots will die after a few minutes of exposure to dry air. Furthermore, the 

 right combination of heat and moisture in bundles can prompt the breaking of dor- 

 mancy, which can be as fatal to seedlings as excessive heat. 



It is seldom possible to plant trees the same day they are delivered from the 

 nursery; therefore, some kind of field storage is necessary. In the past, most stock 

 was heeled-in on the planting site and taken out as needed for immediate planting. 

 In recent years, however, that method has been largely replaced by cold storage 

 accessible to the planting site. 



Heeling-in consists of storing the stock in trenches with the tops exposed and 

 the roots covered with tightly packed damp soil. If this method must be used, as in 

 remote planting sites, storage should be for as brief a time as possible, in damp, 

 shaded soil. After more than a few days, warm weather is liable to cause the plants 

 to break dormancy and start growth; then disturbance is a greater shock than the 

 original lifting and storage. Lifting trees after growth has started may interrupt 

 root growth and delay root initiation after outplanting. 



Bundles of trees can be stored in cold storage plants if these are available near 

 the planting site. Temperature of 33° to 40° F and humidity of 90 to 99 percent is 

 desirable, with free air circulation through the room. 



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