Table 3. Changes in forest area and stock by age classes at Uljin-gun, Gyeongsangbuk-do.

	Age class	2015	2020
Forest area (ha)	I	1,548	2,580
	II	703	659
	III	3,438	1,619
	IV	23,480	20,636
	V	32,720	33,937
	VI	21,121	24,009
	Bamboo	91	59
	Bare-land	1,111	685
	Total	84,212	84,184
Forest stock (m3)	I	0*	0*
	II	30,154	31,961
	III	368,646	190,932
	IV	3,430,468	3,590,949
	V	5,821,035	7,068,170
	VI	4,516,236	5,372,939
	Total	14,166,539	16,254,951
Average forest stock (m3/ha)		168.22	193.09

The first age classes showed no records for the forest stock since the diameters at the breast height (DBH) of the trees showed less than 6 cm, that were discarded for the measurement.