370 Forestry Quarterly 



10. The total growth of whole forests in the Philippines will 

 in many instances be greater than that in a temperate hardwood 

 forest, but the volume production of commercial timber will usu- 

 ally be lower. 



11. Clear cutting over large areas will, in most instances, elimi- 

 nate dipterocarp species from any forest. Clear cutting on small 

 areas will, in many instances, result in a satisfactory stand of 

 dipterocarp reproduction. Selective cutting and culling, if not 

 severe, will merely lower the volume production without seriously 

 changing the species composition, but if continued over long peri- 

 ods will result in the elimination of all dipterocarp species which 

 are cut. A partial cutting followed by a long period of closure 

 seems to be the m"ost satisfactory method of cutting over a dip- 

 terocarp forest. 



12. Present experience seems to indicate that planting of dip- 

 terocarps will not be successful in open lands and probably only 

 moderately successful in second-growth forests or in openings in 

 the high forest. If planting is to be attempted in the Philippines 

 at the present time, species which are easier to handle than dip- 

 terocarps and more valuable at maturity should be chosen. 



13. Heavy stands of dipterocarp forest which are largely over- 

 mature will have to be managed under some modification of the 

 clear-cutting system. Those which contain distinct second and 

 third stories composed partially of dipterocarps and partially of 

 miscellaneous species can be most successfully managed under 

 the shelterwood system. Those in which there is a satisfactory 

 distribution of dipterocarps throughout all size classes can be 

 satisfactorily handled under either the shelterwood system or the 

 selection system with a diameter limit. Those which have been 

 very heavily cut over should be withheld from all cutting until 

 the small dipterocarps in the lower stories become large enough 

 to bear seed. 



A use of the term "rate of growth," indiscrimately, whether 

 current annual, mean annual or periodic annual rate of growth is 

 meant, leads to some confusion in the section on growth, as does 

 also the interchangeable use of the terms management system, 

 method of regulation and silvicultural system under "General 

 Considerations of Management" and under "Effect of Cutting in 

 Dipterocarp Forests." Under the latter section the use of the 

 diameter limit in the northern Laguna Forest is spoken of as a 

 satisfactory method of regulation, although this opinion is not 

 held by all Philippine foresters, and it is nothing but an opinion, 

 as this tract has never been logged as severely as it will be when 

 it is placed under intensive utilization and the full possible 

 cut of the area taken. It is questionable whether under such con- 

 ditions the diameter limit will prove to be satisfactory. Under 



