Pennisetum purpureum

Elephant grass, Napier grass, Uganda grass

Tall erect perennial with thick stems up to 4.5 m high, found on moist soils in areas with over 1 000 mm of rainfall annually and widely distributed along the banks of watercourses. Grows best on deep soils of moderate to fairly heavy texture. Tolerates short droughts, but does not withstand waterlogging. The most widely grown fodder grass. Sometimes grazed for six to eight weeks at a time. Yields very large quantities of dry matter, but is low in protein content unless cut very young. With poor drainage, best grown on raised beds. Should not be cut closer than 10-15 cm from the ground. Under normal management, stands are invaded by weeds and "run out" after two or three years, so that they have to be ploughed up and replanted.

The grass is planted in the same way as sugar cane (Saccharum officinarum L.): the culms are cut into pieces, each with three nodes, and are buried in the soil just deep enough to cover the second node and to leave the third above the ground.

The hybrid Giant Napier (P. purpureum x P. typhoides) has a high sugar content and leaf-stem ratio, but it needs highly fertile soil.

							As % of dry matter
						DM	CP	CF	Ash	EE	NFE	Ref
Fresh, vegetative, 40 cm,
Tanzania						20.0	9.8	29.7	14.0	2.6	43.9	175
Fresh, vegetative, 80 cm,
Tanzania						20.0	9.0	28.6	14.8	1.1	46.5	"
Fresh, early bloom, 240 cm,
Tanzania						25.0	7.2	36.1	12.4	1.0	43.3	"
Fresh, tops only, 220 cm,
Tanzania							13.2	32.9	10.3	2.4	41.2	312
Fresh, cut at intervals of
6 weeks, Malaysia						19.0	10.0	31.6	15.3	2.1	41.0	292
Fresh, cut at intervals of
8 weeks, Malaysia						19.5	9.7	33.3	16.4	1.5	39.1	"
Fresh, cut at intervals of
10 weeks, Malaysia						21.0	7.6	35.2	14.8	1.4	41.0	"
Hay, vegetative, South Africa							15.1	34.9	12.1	2.4	35.5	489
Hay, mature, South Africa							7.5	40.3	11.7	1.4	39.1	"
Silage, 120 cm, Zimbabwe						23.5	6.8	35.8	13.7	0.9	42.8	143
Silage, 210 cm, Zimbabwe						21.4	4.2	35.3	15.2	1.2	44.1	"
Fresh, var. merkeri, late
bloom, Puerto Rica						24.0	8.6	36.1	10.2	3.1	42.0	33
Fresh, var. merkeri, cut
every 6 wks, Malaysia						20.5	9.8	32.2	12.2	1.5	44.3	292
Fresh, var. merkeri, cut
every 8 wks, Malaysia						20.5	8.8	34.6	14.1	1.5	41.0	"
Fresh, var. merkeri, cut
every 10 wks, Malaysia						23.5	7.7	35.7	14.0	0.9	41.7	"
Fresh, Giant Napier, 4
weeks, 50 cm, Thailand						15.8	10.8	28.5	13.9	3.8	43.0	219
Fresh, Giant Napier, 6
weeks, 75 cm, Thailand						17.1	8.8	32.2	12.9	3.5	42.6	"
Fresh, Giant Napier, 8
weeks, 135 cm, Thailand						18.3	8.7	32.8	10.9	3.3	44.3	"
Fresh, Giant Napier, 10
weeks, 150 cm, Thailand						18.5	6.5	33.0	11.4	2.7	46.4	"
Fresh, Giant Napier, 12
weeks, 150 cm, Thailand						20.4	5.9	31.9	10.3	2.9	49.0	"
							Digestibility (%)
					Animal		CP	CF	EE	NFE	ME	Ref
Fresh, vegetative, 40 cm					Sheep		61.2	74.7	50.0	71.8	2.30	175
Fresh, vegetative, 80 cm					Sheep		54.4	60.5	45.0	62.2	1.92	"
Fresh, early bloom,
240 cm					Sheep		50.0	60.1	30.0	52.9	1.79	"
Fresh, tops only					Zebu		73.4	65.7	66.4	57.0	2.17	312
Hay, vegetative					Oxen		73.2	77.2	66.5	67.8	2.44	489
Hay, mature					Oxen		40.7	56.0	30.9	33.8	1.46	"
Merker grass, late bloom					Sheep		66.0	61.0	57.0	58.0	2.06	143
Giant Napier, 75 cm					Sheep		33.0	62.0	53.0	62.0	1.94	"
Giant Napier, 135 cm					Sheep		38.0	64.0	53.0	58.0	1.96	33
Giant Napier, 10 weeks,
150 cm					Sheep		50.0	60.0	54.0	54.0	1.87	219
Giant Napier, 12 weeks,
150 cm					Sheep		28.0	60.0	39.0	54.0	1.81	"
					Nylon bag degradability
						a	b	c		12hr	48hr	Ref
						(%)	(%)	(/hour)		(%)	(%)
Elephant grass, Portugal					DM	12.9	45.4	0.0214			43.7	627
	[P (rumen degradability at time t) = a+b*(1-exp(-c*t))]
		Amino acid composition as % of crude protein
Leaf											Ref	376
Arg	Cys	Gly	Hys	Ils	Leu	Lys	Met	Phe	Thr	Try	Tyr	Val
2.1	0.2	-	1.9	4.7	6.2	3.1	1.4	7.3	3.8	0.6	4.9	5.9