SYLVICULTURE. 



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

 planted groups. 



da. 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 

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

 only storm-firm species will answer. It is wise to leave the stand- 

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

 inflicting 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- 

 teaded, 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 

 155. Very good soil and short rotations allow of an increased num- 

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

 iorms 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 is maintained in distinctly separate tiers. 



Species adapted to form the lower leaf canopy are; Beech, 

 Hard Maple, Black Gum, Firs, Hemlocks. The species in the upper 

 story had better have a light-demanding character. The form is 

 created by raising a polewood (even-aged) of Yellow Pine, Oak, 

 Hickory, Larch, etc.; by early and heavy thinnings from below; by 

 very heavy thinnings after the completion of the principal height 

 growth (year forty to sixty) ; and by planting at the same time 

 either seeds or preferably seedlings of shade-bearing 1 species. Should 

 the undergrowth catch up with the upper growth, either the one 

 or the other must be removed. The undergrowth preserves the fer- 

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