pine, and lodgepole pine. A particular disease or insect may dictate the choice of 

 cutting methods. Generally, managers try to maintain a mixture of tree species so 

 that no one pest will destroy the entire stand. 



Clearcutting followed by planting insures a mixture of species in the stand; it 

 both protects the stand from disease and promotes growth. Where disease and insects 

 are not major problems, any of the high-forest cutting methods are possible, depending 

 on the management objectives. Single-tree selection cuttings promote the natural 

 succession toward pure Douglas-fir, the most shade-tolerant species. Ponderosa pine 

 germinates and survives for 30 to 40 years in the shade, but eventually it ceases to 

 reproduce and is eliminated from the stand. Therefore, the manager should not use 

 single-tree selection cutting if he intends to keep ponderosa pine in the stand. 



Group selection, seed-tree, or shelterwood cuttings can provide for stands of 

 mixed species composition. Group selection cutting creates small openings of 0.25 to 

 2 acres in which all four species will regenerate and grow well following adequate 

 site preparation. Seed-tree and shelterwood cuttings require additional treatments to 

 encourage seed germination. Then the seed trees should be removed shortly after the 

 reproduction stand becomes established to promote growth of pine and larch seedlings. 



Ponderosa pine grows best on sites of the Abies gvandis-Pachistima myvsinites 

 habitat type. Natural reproduction is less sporadic and more dependable than in the 

 drier pine habitats. It will not persist, however, unless satisfactory conditions are 

 present, particularly freedom from overhead shade. Grand fir and Douglas-fir are more 

 competitive than ponderosa pine on these moist sites, and in dense stands they eventu- 

 ally overtop and eliminate pine from the stand. Therefore, cutting methods must provid 

 sufficient light for ponderosa pine. In addition, stands of this type are often sub- 

 ject to serious damage from insects and diseases. Both grand fir and Douglas-fir are 

 attacked by spruce budworm, for example. Grand fir is very susceptible to heart-rot 

 fungi that weaken the trees in addition to destroying much of the wood. The impact 

 of these diseases and insects becomes greater with advancing age of the stand. Under 

 these circumstances, management systems, such as single-tree selection, which lengthen 

 the rotation and increase the proportion of shade-tolerant species, may encourage 

 insects and diseases. Even-aged management of these stands through shorter rotations 

 leads to healthier and more productive forests, with conditions that allow ponderosa 

 pine to form a valuable component of the stand. 



As in other habitats, clearcutting and planting create the desired conditions for 

 ponderosa pine most simply. It is important that the planted trees be from a seed 

 source within this habitat type. Again, group selection and seed-tree methods can be 

 successful if they are properly executed. 



This evaluation of reproduction cutting methods in various habitat types is based 

 partly on observation of actual practice but largely on the silvical requirements of 

 ponderosa pine. All the cutting methods have been tested in the territory discussed 

 here, though not under all conditions. There is still a need to explore the effects 

 of the various methods in terms of values other than production of timber. 



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