232 



GOVERNMENT REGULATION AND WORKING PLANS 



Method of regulating the cut 



System of cutting 



Pure area 



Pure area 



Pure area 



Pure area 



Diameter limit by single trees 



Area and thickness of bark 



Area and age 



Method of 1883 



Area — volume allotment by periods 



(rt) Coppice (clear cut) page 232. 

 (b) Resin crops, page 232. 

 ((■) Intermediate fellings, page 233. 

 (f/) Selection high forest (solely for pro- 

 tection), page 233. 

 (e) Coppice (selection), page 233. 

 (J) Cork bark, page 233. 

 ig) Coppice-under-standards, page 234. 

 (h) Selection high forest, page 234. 

 (i) Even-aged high forest, page 239. 



Pure Area. — The underlying principle is to divide the area to be cut 

 over into a number of equal cutting areas corresponding to the number 

 of years in the rotation. 



(a) Coppice {clear cut). — If there are wide variations in soil quality, 

 which would necessarily mean a variation in yield per acre, then the 

 fixed area to be cut over each year can be increased or decreased so as 

 to equahze the cut. 



Illustration. — If a coppice forest of 250 acres had a 20-year rotation 

 with three-fifths the area producing 10 cords at the end of 20 years and 

 two-fifths the area only producing 5 cords, then the area cut over would 

 be 10 acres per year for 15 years, and 20 acres per year for 5 years when 

 the poorer soil came to be logged. Certain principles govern the designa- 

 tion of the cutting areas on the ground. If the forest is small, say 30 

 acres, it is better with a 30-year rotation to divide into fifteen or ten 

 cutting areas, making a cut of 2 acres every other year, or 3 acres every 

 three years. If possible similar types should be grouped into one cutting 

 unit unless this interferes with the logging plan. Obviously it is poor 

 policy to divide the coppice without seeing to its practicability as a 

 logging unit. Broilliard favors rectangular cutting areas, say 1,500 by 

 600 feet. It is better to follow contours or logging roads in establishing 

 coupe boundaries on hilly ground than to adhere rigidly to rectangles. 

 The coppice cutting order should be against the prevailing storm direc- 

 tion and it should be numbered in the order of cutting. When coppice 

 rotations are lengthened or shortened the redivision of the cutting areas 

 is usually an interesting puzzle which can be solved only after careful 

 study on the ground. 



(6) Resin crops. — Both the final and intermediate yields are regu- 

 lated by working over equal areas each year. No attempt is made 

 to get a more exact yield by taking into account the soil productivity. 

 For a detailed description of the system of working and an illustration 

 of yield regulation see pages 191 and 192, Chapter VIII. The final 

 yield of these maritime pine forests is also regulated by cutting equal 



