Evaluation of organic fertilizer sources for south-eastern (USA) turfgrass maintenance

Figures & data

Table I. Fertilizer treatments used in the creeping bentgrass (2010) and hybrid bermudagrass (2009 and 2010) trials, Auburn, AL.

Trade name	Analysis	%N w/w	SGN^‡	Nutrient source
(Abbreviation)	N-P2O5-K2O	AMM/WSN/WIN
Milorganite (MILORG)	6-2-0	0/0.75/5.25	90	composted sewage sludge
Nature Safe Starter (NSS)	5-6-6	0.2/0.3/4.5	170	meat, blood, bone, and fish meals, and langbeinite
Nature Safe StressGuard (NSSG)	8-3-5	0.2/0.6/7.2	160	hydrolyzed feather, meat, bone, poultry, and fish meals, and langbeinite
Scotts Turf Builder (STB)^†	26-2-13	2.8/9.6/0.9 12.7% urea N	90	methylene urea
Sustane® (ST4)	4-6-4	0.4/0.4/3.2	200	aerobically composted turkey litter, feather meal, sulfate of potash
Sustane® (ST8)^†	8-2-4	0.4/0.4/7.2	100	aerobically composted turkey litter, hydrolyzed feather meal, and sulfate of potash
Fine/Regular (TOPF/TOPR)	4-2-2	0.0/0.42/3.58	100/170	poultry litter and feather meal
Urea (UREA)	46-0-0	46% urea N	110	(NH2)2CO
AMM = ammoniacal nitrogen, WSN = water-soluble nitrogen, WIN = water-insoluble nitrogen, ^‡SGN = Size Guide Number, which is the average particle diameter in millimeters, multiplied by 100.
^†Not included in the 2009 experiment.

Table II. Fertilizer removal (g m⁻²) via mower pick-up, 2010 studies, Auburn, AL. Creeping bentgrass was managed as a putting green whilst the hybrid bermudagrass was maintained at fairway height.

	Penn G-2 creeping bentgrass			Tifway bermudagrass
	Day of mowing (weeks after treatment)
N Source	Jan 25 (1)	Feb 1 (2)	Feb 8 (3)	May 11 (1)	May17 (2)
	g m^−2
UREA^‡	0 e^†	0 d	0 e	0.0 c	0 c
MILORG	1.9 cde	0.4 cd	0.3 d	0.5 c	0 c
NSS	1.7 cde	0.5 cd	0.4 cd	16.8 bc	0 c
NSSG	0.8 de	0.6 bc	0.3 d	1.4 c	0 c
ST4	9.6 a	1.5 a	1.0 a	41.8 a	10.5 a
ST8	2.1 cd	0.5 cd	0.4 cd	21.9 b	4.3 b
STB	0 e	0 d	0 e	0.5 c	0 c
TOPF	4.0 b	0.9 b	0.7 b	7.9 bc	0 c
TOPR	3.1 bc	0.7 bc	0.6 bc	1.5 c	0 c
CNTRL	0 e	0 d	0 e	0.0 c	0 c
^†within each sampling date means followed by the same letter are not significantly different from each other via Means separation at alpha = 0.05.
^‡UREA – Urea (46-0-0), MILORG-Milorganite (6-2-0), NSS – Nature Safe Starter (5-6-6), NSSG – Nature Safe StressGuard (8-3-5), ST4 – Sustane (4-6-4), TOPF – Top Organic Fine Grade (4-2-2), TOPR – Top Organic Regular Grade (4-2-2), CNTRL – unfertilized control.

Figure 1.  Relative colour of hybrid bermudagrass and creeping bentgrass as affected by N fertilizer source, Auburn, AL, 2009 and 2010. Vertical bars are the standard error about the mean.

Table III. Clipping yield (g dry matter m⁻²) and N content (g N kg⁻¹ tissue) of hybrid bermudagrass and creeping bentgrass at selected sampling dates as affected by N source, 2009 and 2010, Auburn, AL.

	Hybrid bermudagrass						Creeping bentgrass
Trt	9 June 2009 (6 WAT)		14 June 2010 (6 WAT)		6 July 2010 (9 WAT)		1 March 2010 (6 WAT)		22 March 2010 (9 WAT)
	yield	N	yield	N	yield	N	yield	N	Yield	N
UREA^‡	3.5 a	27 a	35 ab	33 ab	46 a	35 a	2.1 a	31 a	8.2 a	39 a
MILORG	1.8 c	26 a	17 def	34 ab	32 bc	34 a	1.2 b	29 a	5.0 c	33 bc
NSS	3.1 ab	22 a	27 bcd	34 ab	38 abc	34 a	1.2 b	30 a	6.2 b	33 bc
NSSG	2.1 bc	27 a	29 abc	34 ab	38 abc	35 a	1.4 b	32 a	5.4 c	34 bc
ST4	1.0 c	25 a	15 ef	33 ab	34 abc	34 a	1.4 b	30 a	5.4 c	32 bc
ST8	NA^††	NA	22 cde	36 a	35 abc	27 a	1.5 b	31 a	5.4 c	34 bc
STB	NA	NA	39 a	34 ab	33 bc	34 a	1.5 b	30 a	6.0 b	36 b
TOPF	1.4 c	25 a	14 ef	32 ab	39 abc	34 a	1.3 b	29 a	5.1 c	31 bc
TOPR	1.8 c	26 a	15 ef	30 b	45 ab	35 a	1.5 b	29 a	5.6 bc	33 bc
CNTRL	1.9 bc	24 a	9 f	30 b	29 c	34 a	0.8 c	25 b	3.5 d	30 c
^†within each sampling date means followed by the same letter are not significantly different from each other via Means separation at alpha = 0.05.
^‡UREA – Urea (46-0-0), MILORG – Milorganite (6-2-0), NSS – Nature Safe Starter (5-6-6), NSSG – Nature Safe StressGuard (8-3-5), ST4 – Sustane (4-6-4), TOPF – Top Organic Fine Grade (4-2-2), TOPR – Top Organic Regular Grade (4-2-2), CNTRL – unfertilized control.
^††Not included in the 2009 experiment.

Table IV. Shoot density of harvested creeping bentgrass and hybrid bermudagrass (shoots cm⁻²) as affected by sampling date and N treatment, Auburn, AL, 2009 and 2010.

	Creeping bentgrass			Hybrid bermudagrass
	2010			2009	2010
Trt	1 Feb (2 WAT)	22 Mar (8 WAT)	12 April (11 WAT)	21 July (12 WAT)	2 June (4 WAT)	6 July (9 WAT)	27 July (12 WAT)
	shoots cm^−2
UREA^‡	7.5 ab^†	9.0 a	7.2 a	3.9 a	6.5 a	5.3 a	5.4 a
MILORG	7.5 ab	9.3 a	7.8 a	3.9 a	6.1 ab	5.3 a	5.0 a
NSS	7.5 ab	7.2 b	6.3 a	3.6 ab	5.8 ab	5.5 a	5.1 a
NSSG	7.5ab	8.1 ab	6.3 a	4.1 a	6.0 ab	5.4 a	4.9 a
ST4	8.4 a	8.7 ab	7.8 a	3.5 ab	5.4 ab	6.4 a	4.8 a
ST8	7.5 ab	7.5 ab	7.5 a	NA^††	5.1 b	5.8 a	5.2 a
STB	8.7 a	9.6 a	6.9 a	NA	5.0 b	5.1 a	4.8 a
TOPF	7.5 ab	8.4 ab	7.5 a	3.5 ab	6.1 ab	6.2 a	5.2 a
TOPR	7.8 ab	7.8 ab	6.9 a	3.8 a	5.5 ab	5.3 a	5.2 a
CNTRL	6.0 b	7.8 ab	6.6 a	3.0 b	5.5 ab	5.3 a	4.4 a
^†within each sampling date means followed by the same letter are not significantly different from each other via Means separation at alpha = 0.05.
^‡UREA – Urea (46-0-0), MILORG – Milorganite (6-2-0), NSS – Nature Safe Starter (5-6-6), NSSG – Nature Safe StressGuard (8-3-5), ST4 – Sustane (4-6-4), TOPF – Top Organic Fine Grade (4-2-2), TOPR – Top Organic Regular Grade (4-2-2), CNTRL – unfertilized control.
^††Not included in the 2009 experiment.