SYLVICULTURE 



cc. Form raised by planting seeds or seedlings over whole 

 compartments. 



dd. Form raised by underplanting seeds or seedlings over 

 whole compartments, followed by (gradual) removal of the super- 

 structing trees within less than 25 years. 



2. Uneven-aged cultured forms, when the age-classes mixed 

 within a compartment differ by over 25 years. 



aa. Form emanating from the long-time-shelterwood compart- 

 ment type of n. s. r. 



bb. Form emanating from strip types, either restocked by n. s. r. 

 or by planting. 



cc. Form emanating from group types of n. s. r., or from planted 

 groups. 



dd. Form emanating from selection types of n. s. r. 



b. Auxiliary cultured forms of high forest: 



aa. Form of standards in high forest, when a limited number 

 of trees are left to grow amongst and with the young growth for a 

 longer or shorter number of years. 



The standards might be left either in scattering groups or in- 

 dividually scattered over the second growth. In the latter case, 

 only storm-fii'm species will answer. It is wise to leave the standards 

 in the proximity of roads so as to allow their removal without in- 

 flicting damage on the young growth. Species well adapted for 

 standards are: Yellow Pines, Larches, White Oaks, Yellow Poplar, 

 Black Locust. Hickory, Walnut, Black Cherry. Shade-bearers and 

 flat-rooted species will not answer the purpose. 



It is unwise to leave standards unprepared by preceding cuttings 

 for the life in the open. Standards set suddenly free will cover 

 themselves rapidly with adventitious branches, will grow stag- 

 headed, will suffer from storm and sleet, and will die without yield- 

 ing the results for which they were left. 



Where the standards shade the young growth too badly, it may 

 be necessary to remove their lower live branches. 



The number of standards left per acre does not usually exceed 

 25. Very good soil and short rotations allow of an increased number. 

 Standards may be, but need not be, of the same species which forms 

 the undergrowth. 



Where the standards do not belong, approximately, to one and 

 the same age-class, there the standard form bastardizes with the 

 uneven-aged forms emanating from the group-type or from the 

 selection type of n. s. r. 



bb. Form of two-storied high forest, when an upper and a 

 lower leaf canopy i maintained in distinctly separate tiers. 



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