Nitrogen Immobilization in Plant Growth Substrates: Clean Chip Residual, Pine Bark, and Peatmoss

Table 2

Particle size analysis of clean chip residual, pine bark, and peatmoss substrates.

U.S. standard sieve no.	Sieve opening (mm)		Substrate^z
		0.48 cm CCR	0.95 cm CCR	PB	PM
1/2	12.50	0.0 a^y	0.0 a	0.0 a	2.2 a
3/8	9.50	0.0 b	0.0 b	0.1 b	8.2 a
1/4	6.35	0.0 d	2.7 c	6.0 b	11.0 a
6	3.35	0.8 c	23.9 a	24.0 a	17.0 b
8	2.36	8.8 c	20.0 a	12.6 b	9.1 c
10	2.00	7.9 a	8.1 a	5.0 b	3.5 c
14	1.40	19.0 a	13.2 b	11.3 c	9.0 d
18	1.00	12.4 a	8.2 b	9.1 b	9.0 b
35	0.50	13.0 b	7.7 c	13.8 ab	15.1 a
60	0.25	12.1 a	7.8 b	8.4 b	9.4 b
140	0.11	15.1 a	7.0 b	5.1 b	5.0 b
270	0.05	5.8 a	0.9 c	2.5 b	1.1 c
pan	0.00	5.1 a	0.5 c	2.1 b	0.4 c
Texture^x
Coarse		0.8 c	26.6 b	30.0 b	38.3 a
Medium		48.0 a	49.5 a	38.0 b	31.0 c
Fine		51.2 a	23.9 c	32.0 b	30.7 b

^zCCR: clean chip residual, PB:  pine bark, and PM:  sphagnum peatmoss.
^yPercent weight of sample collected on each screen, means within row followed by the same letter are not significantly different based on Waller-Duncan 𝑘 ratio 𝑡-tests at 𝛼  =  0.05 (𝑛  =  3).
^xCoarse: >3.35 mm, Medium:  >1.00–<3.35 mm and Fine:  <1.0 mm.