Knoxville mean biomass, nitrogen content, and nitrogen release

Table 11-a. By location mean biomass, percent total nitrogen content‡, and estimated nitrogen release§ of 60 cover crop varieties evaluated in small plot replicated trials at the University of Tennessee East Tennessee AgResearch and Education Center in Knoxville, TN during 2019-2020.

Variety	Common Name	Group	Biomass (DM tons/ac)				Total Nitrogen (%)				Estimated N Released: Apr. Term. (lbs/ac)			Estimated N Released: May. Term. (lbs/ac)
			Apr†		May		Apr		May		2 wks.	4 wks.	12 wks.	2 wks.	4 wks.	12 wks.
Brassicas
Impact	Collards	Brassica	0.6	L-T	0.7	J-P	2.1	L-O	1.7	M-O	1	1	10	1	2	17
Extender	Hyb. Brassica	Brassica	0.5	M-T	1.3	F-O	1.6	O-U	1.4	O-Q	0	0	4	0	0	4
Viva	Hyb. Brassica	Brassica	0.8	I-Q	1.7	C-L	1.9	M-Q	1.2	P-U	0	1	9	0	0	6
Vivant	Hyb. Brassica	Brassica	0.3	Q-T	0.7	K-P	2.2	K-N	1.6	N-P	0	1	5	0	1	7
Aerifi	Radish	Brassica	0.8	J-R	1.8	B-K	1.6	O-U	1.3	O-S	0	1	6	0	0	10
Digger	Radish	Brassica	0.7	K-R	2.1	B-I	1.9	M-Q	1.4	O-Q	0	1	8	0	1	15
Driller	Radish	Brassica	0.4	N-T	1.8	B-K	1.7	N-R	1.4	O-R	0	0	4	0	1	13
SERALPHA	Radish	Brassica	0.9	H-P	2.6	B-D	1.8	N-R	1.4	O-Q	0	1	9	0	1	20
SERWF19	Radish	Brassica	1	F-N	2	B-I	1.7	N-S	1.1	Q-V	0	1	8	0	0	6
Smart	Radish	Brassica	1.1	E-L	2.2	B-H	1.6	O-T	1.3	O-S	0	1	8	0	1	12
Jackpot	Turnip	Brassica	0.7	K-S	1.3	F-O	2	M-P	1.3	O-Q	0	1	8	0	0	7
Average			0.7		1.7		1.8		1.4		0	1	7	0	1	11
Min			0.3		0.7		1.6		1.1		0	0	4	0	0	4
Max			1.1		2.6		2.2		1.7		1	1	10	1	2	20
Range			0.8		1.9		0.6		0.5		1	1	6	1	2	16

† Varieties that have any MS letter in common are not significantly different (Fisher’s Protected LSD, P<0.05). Mean separation was performed across all entries. Varieties within the “A group” were top performers across all entries and mean separation letters of these entries are highlighted in dark orange.
For ease of viewing, the table is broken into functional groups (brassicas, cereals, legumes). Mean values for top performers within each functional group are highlighted in light orange (50th – 75th percentile) and dark orange (> 75th percentile).
‡ Analyzed using near infrared spectroscopy (NIRS) with the appropraite calibration for each species.
§ Estimated using quality constituents from NIRS inputted into the UGA cover crop nitrogen calculator.

 

Table 11-b. By location mean biomass, percent total nitrogen content‡, and estimated nitrogen release§ of 60 cover crop varieties evaluated in small plot replicated trials at the University of Tennessee East Tennessee AgResearch and Education Center in Knoxville, TN during 2019-2020.

Variety	Common Name	Group	Biomass (DM tons/ac)				Total Nitrogen (%)				Estimated N Released: Apr. Term. (lbs/ac)			Estimated N Released: May. Term. (lbs/ac)
			Apr†		May		Apr		May		2 wks.	4 wks.	12 wks.	2 wks.	4 wks.	12 wks.
Cereals
Centurion	Annual Ryegrass	Cereal	0.3	P-T	0.7	K-P	1.5	P-V	1.1	Q-V	0	0	3	0	0	4
Lowboy	Annual Ryegrass	Cereal	0.1	T	0.2	OP	1.7	N-R	1.3	O-T	0	0	1	0	0	2
140760	Barley	Cereal	0.7	K-R	2	B-I	1.1	V-X	0.8	U-W	0	0	1	0	-1	-2
140789	Barley	Cereal	1.1	E-L	2.2	B-I	1.2	S-X	0.9	R-W	0	0	4	0	0	1
140797	Barley	Cereal	0.7	J-R	1.7	B-L	1.2	T-X	0.9	R-W	0	0	2	0	0	0
SB255	Barley	Cereal	0.6	L-T	1.2	G-P	1.4	Q-W	0.9	S-W	0	0	3	0	0	1
Secretariat	Barley	Cereal	0.8	I-R	1.7	C-M	1.5	Q-V	0.8	T-W	0	0	5	0	-1	-1
Bates RS4	Cereal Rye	Cereal	2.1	A	3.9	A	1	WX	0.5	W	0	0	-1	0	0	-9
Elbon (1)	Cereal Rye	Cereal	1.5	B-G	2.9	AB	1.2	S-X	0.5	W	0	0	2	0	0	-8
Elbon (2)	Cereal Rye	Cereal	1	E-M	2.1	B-I	1.3	R-X	0.7	W	0	0	3	0	0	-4
Goku	Cereal Rye	Cereal	1.2	D-K	2.3	B-H	1	V-X	0.6	W	0	0	0	0	0	-6
NF95319B	Cereal Rye	Cereal	1.7	A-D	2.7	B-D	0.9	X	0.5	W	0	0	-1	0	0	-8
NF97325	Cereal Rye	Cereal	2	AB	2.3	B-H	0.9	X	0.5	W	0	0	-2	0	0	-8
NF99362	Cereal Rye	Cereal	1.5	A-F	2.6	B-E	0.9	X	0.5	W	0	0	-1	0	0	-8
Wintergrazer 70	Cereal Rye	Cereal	1.3	D-J	2.1	B-I	1	V-X	0.7	W	0	0	0	0	0	-5
Yankee	Cereal Rye	Cereal	0.7	J-R	1.9	B-I	1.5	P-V	0.9	S-W	0	0	4	0	0	-1
Bob	Oat	Cereal	1.1	E-M	2.5	B-F	1.1	V-X	0.7	VW	0	0	3	0	-1	-6
Cosaque	Oat	Cereal	0.9	G-O	2	B-I	1.1	U-X	0.8	U-W	0	0	2	0	-1	-1
Hilliard	Wheat	Cereal	1.2	D-K	2.3	B-H	1.2	R-X	0.7	VW	0	0	4	0	-1	-6
Liberty 5658	Wheat	Cereal	0.6	L-T	1.6	D-M	1.1	V-X	0.7	VW	0	0	1	0	-1	-4
Average			1.1		2		1.2		0.8		0	0	2	0	0	-3
Min			0.1		0.2		0.9		0.5		0	0	-2	0	-1	-9
Max			2.1		3.9		1.7		1.3		0	0	5	0	0	4
Range			2		3.7		0.9		0.8		0	0	7	0	1	13

† Varieties that have any MS letter in common are not significantly different (Fisher’s Protected LSD, P<0.05). Mean separation was performed across all entries. Varieties within the “A group” were top performers across all entries and mean separation letters of these entries are highlighted in dark orange.
For ease of viewing, the table is broken into functional groups (brassicas, cereals, legumes). Mean values for top performers within each functional group are highlighted in light orange (50th – 75th percentile) and dark orange (> 75th percentile).
‡ Analyzed using near infrared spectroscopy (NIRS) with the appropraite calibration for each species.
§ Estimated using quality constituents from NIRS inputted into the UGA cover crop nitrogen calculator.

 

Table 11-c. By location mean biomass, percent total nitrogen content‡, and estimated nitrogen release§ of 60 cover crop varieties evaluated in small plot replicated trials at the University of Tennessee East Tennessee AgResearch and Education Center in Knoxville, TN during 2019-2020.

Variety	Common Name	Group	Biomass (DM tons/ac)				Total Nitrogen (%)				Estimated N Released: Apr. Term. (lbs/ac)			Estimated N Released: May. Term. (lbs/ac)
			Apr†		May		Apr		May		2 wks.	4 wks.	12 wks.	2 wks.	4 wks.	12 wks.
Legumes
FIXatioN	Clover, Balansa	Legume	0.3	Q-T	1.2	G-P	3.1	C-G	2.4	E-J	0	1	9	2	4	33
Paradana	Clover, Balansa	Legume	0.2	R-T	0.5	M-P	2.3	J-M	2.1	I-M	0	1	5	1	1	11
Viper	Clover, Balansa	Legume	0.6	L-T	2.6	B-E	3.1	D-H	2.4	D-I	1	2	18	4	8	66
Balady	Clover, Berseem	Legume	0.1	T	0.1	P	1.7	O-T	2.7	C-F	0	0	1	0	0	3
Frosty	Clover, Berseem	Legume	0.1	ST	0.3	N-P	2.6	G-K	2.3	F-L	0	0	2	1	1	8
AU Sunrise	Clover, Crimson	Legume	0.7	J-R	1.7	C-L	2.8	F-J	2	L-N	1	2	18	1	3	28
Bolsena	Clover, Crimson	Legume	0.6	L-T	1.7	B-L	2.9	D-I	2	I-M	1	2	15	2	3	31
Dixie	Clover, Crimson	Legume	0.8	J-R	1.2	G-P	2.6	G-K	2	I-N	1	2	17	1	3	21
Kentucky Pride	Clover, Crimson	Legume	0.2	Q-T	1	I-P	2.6	H-K	2.2	H-L	0	1	6	1	3	22
SECCM18	Clover, Crimson	Legume	0.9	G-O	2.3	B-G	2.7	G-J	2	K-N	1	3	22	2	4	39
White Cloud	Clover, Crimson	Legume	0.4	O-T	1.1	H-P	2.5	I-L	1.9	L-N	0	1	8	1	2	19
Big Red	Clover, Red	Legume	0.1	ST	0.6	L-P	2.7	G-J	2.6	C-H	0	0	2	1	2	16
Blaze	Clover, Red	Legume	0.1	T	0.3	N-P	2.7	G-K	2.7	C-E	0	0	2	1	1	10
GA9909	Clover, Red	Legume	0.2	R-T	1.2	G-P	2.8	E-I	3.3	B	0	1	6	3	6	42
VNS	Clover, Red	Legume	0.1	T	0.4	N-P	2.3	J-M	2.6	C-H	0	0	1	1	1	11
VNS	Vetch, Common	Legume	1	F-N	3	A-C	3.2	C-F	2.2	G-L	2	3	27	4	9	79
AU Merit	Vetch, Hairy	Legume	1.9	A-C	2.5	B-F	4.3	A	3.9	A	4	9	70	6	13	99
Patagonia Inta	Vetch, Hairy	Legume	1.4	B-H	2.2	B-H	3.1	D-H	2.7	C-F	2	5	35	3	7	51
Purple Bounty	Vetch, Hairy	Legume	0.9	G-O	1.9	B-I	3.9	AB	2.9	BC	2	4	33	3	7	54
Villana	Vetch, Hairy	Legume	0.6	L-T	1.6	D-M	3.1	C-G	2.4	E-K	1	2	16	2	5	36
WinterKing	Vetch, Hairy	Legume	1.6	A-E	1.6	D-M	3.6	BC	2.8	CD	3	6	48	3	6	44
Namoi	Vetch, Woolypod	Legume	1.4	C-I	1.8	B-K	3.3	C-E	2.9	BC	2	5	36	3	6	46
Double OO	Winter Pea	Legume	1	F-N	1.8	B-K	2.6	I-L	2.3	F-L	1	3	20	2	5	42
Survivor	Winter Pea	Legume	1	G-N	2.1	B-I	2.6	I-L	2.7	C-F	1	3	20	4	8	59
VNS (1)	Winter Pea	Legume	0.6	L-T	1.9	B-J	2.5	I-L	2	J-N	1	2	12	2	4	37
VNS (2)	Winter Pea	Legume	0.9	H-P	2.1	B-I	2.8	F-I	3	BC	1	3	20	4	8	60
Windham	Winter Pea	Legume	0.7	K-S	1.7	B-L	3.4	B-D	2.6	C-G	1	3	20	3	6	48
WyoWinter (1)	Winter Pea	Legume	0.7	K-S	2	B-I	2.6	G-K	2.2	G-L	1	2	14	2	5	42
WyoWinter (2)	Winter Pea	Legume	0.5	M-T	1.4	E-N	2.7	F-J	2.8	C-E	1	2	15	2	5	39
Average			0.7		1.5		2.9		2.5		1	2	18	2	5	38
Min			0.1		0.1		1.7		1.9		0	0	1	0	0	3
Max			1.9		3		4.3		3.9		4	9	70	6	13	99
Range			1.8		2.9		2.7		2		4	9	69	6	13	96

† Varieties that have any MS letter in common are not significantly different (Fisher’s Protected LSD, P<0.05). Mean separation was performed across all entries. Varieties within the “A group” were top performers across all entries and mean separation letters of these entries are highlighted in dark orange.
For ease of viewing, the table is broken into functional groups (brassicas, cereals, legumes). Mean values for top performers within each functional group are highlighted in light orange (50th – 75th percentile) and dark orange (> 75th percentile).
‡ Analyzed using near infrared spectroscopy (NIRS) with the appropraite calibration for each species.
§ Estimated using quality constituents from NIRS inputted into the UGA cover crop nitrogen calculator.

 

Table 11-d. Summary statistics and ANOVA p-values for by location mean biomass, percent total nitrogen content‡, and estimated nitrogen release§ of 60 cover crop varieties evaluated in small plot replicated trials at the University of Tennessee East Tennessee AgResearch and Education Center in Knoxville, TN during 2019-2020.

Group	Biomass (DM tons/ac)		Total Nitrogen (%)		Estimated N Released: Apr. Term. (lbs/ac)			Estimated N Released: May. Term. (lbs/ac)
	Apr†	May	Apr	May	2 wks.	4 wks.	12 wks.	2 wks.	4 wks.	12 wks.
Brassicas
Average	0.7	1.7	1.8	1.4	0	1	7	0	1	11
Min	0.3	0.7	1.6	1.1	0	0	4	0	0	4
Max	1.1	2.6	2.2	1.7	1	1	10	1	2	20
Range	0.8	1.9	0.6	0.5	1	1	6	1	2	16
Cereals
Average	1.1	2	1.2	0.8	0	0	2	0	0	-3
Min	0.1	0.2	0.9	0.5	0	0	-2	0	-1	-9
Max	2.1	3.9	1.7	1.3	0	0	5	0	0	4
Range	2	3.7	0.9	0.8	0	0	7	0	1	13
Legumes
Average	0.7	1.5	2.9	2.5	1	2	18	2	5	38
Min	0.1	0.1	1.7	1.9	0	0	1	0	0	3
Max	1.9	3	4.3	3.9	4	9	70	6	13	99
Range	1.8	2.9	2.7	2	4	9	69	6	13	96
Across Groups
Average	0.8	1.7	2.1	1.7	0	1	11	1	2	19
Standard Error	0.1	0.3	0.1	0.1	0	0	2	0	0	3
Min	0.1	0.1	0.9	0.5	0	0	-2	0	-1	-9
Max	2.1	3.9	4.3	3.9	4	9	70	6	13	99
Range	2	3.8	3.4	3.5	4	9	72	6	14	108

‡ Analyzed using near infrared spectroscopy (NIRS) with the appropraite calibration for each species.
§ Estimated using quality constituents from NIRS inputted into the UGA cover crop nitrogen calculator.