Napier Grass
Local names in Kenya ( Elephant grass; Elusii (Luhya))
Scientific Name ( Pennisetum purpureum Schumach)
Napier grass in early growth stage Napier grass in later growth stages profuse hair on leaf sheath and leaf surface
Overview
Napier grass grows tall up to 4 metres, and forms robust bamboo-like clumps. It has a perennial life cycle and is propagated vegetatively. It has a profuse root system, penetrating deep into the soil, and an abundance of fibrous roots spreading into the top soil horizons. The rhizomes (underground stem) are short and creeping and nodes develop fine roots and culms. Its deep root system enables survival under drought. It can be cultivated on bunds and along water channels. It is easy to establish and persistent; suitable for cutting and very good for silage making.
Napier grass constitutes between 40 to 80% of the forage for the smallholder dairy farmers in Western Kenya and has advantages over other grasses as cut-and-carry fodder because of its high yielding capacity and ease of propagation, and management within a wide ecological range (0 ≤ 2,000m above sea level). It is multi-cut and can yield fodder for 3-4 years. Crude protein ranges from 8-11% and the immature crop contains Oxalates as toxin. It has high biomass production, at about 40 tons fresh matter per hectare (ha)/year and can be harvested 4–6 times per year.
Napier grass has a wide range of ecological adaptation and therefore can be grown under wide environmental conditions.
Select a site that falls within the following agro ecological conditions:
Altitude range: Napier grass can be grown at altitudes ranging from sea level to 2,000m above sea level. When grown at altitudes above 2000 m, growth and regeneration after cutting is slow and it may die due to frost.
Rainfall: Napier grass does best in high rainfall areas, over 1500 mm per year. It is however very drought tolerant and can be used as dry season reserve in dry areas.
Temperature range: Napier grass grows well in all tropical and subtropical regions. Day temperatures of 30–35°C are optimum for its growth and no growth takes place below 10°C.
Soil type and conditions: Napier grass can grow in almost all type of soils, from sandy to clayey but does best in deep, fertile, well-draining soils. It is susceptible to waterlogging.
Napier grass is grown in well-prepared land.
For good establishment, the land should be ploughed to a good tilth. Use a tractor, ox plough or dip digging using a jembe to ensure deep tillage.
The choice of variety depends on locality, consumer and market preferences and disease tolerance
Recommended varieties include;
- Napier varieties/clones tolerant to stunt disease currently being promoted in western Kenya where stunt disease is a serious problem are South Africa, Ouma 2 and 3.
Napier grass South Africa Variety
Napier grass Ouma Variety
- Newly identified Napier varieties/clones tolerant to stunt and smut disease that are being multiplied by Kenya Agricultural and Livestock Research Organization are: ILRI accession 16806, ILRI accession 16782, ILRI accession 16789, ILRI accession 16805, ILRI accession 16811, ILRI accession 16783, ILRI accession 16800, ILRI accession 16835
Napier grass ILRI Accession 16806 at KALRO NRI Kakamega
Napier grass ILRI Accession 16782 at ILRI Campus, Nairobi
- Bana grass: leafy and with few silica hairs, which cause irritation during handling. However, it is susceptible to Napier grass head smut disease (Ustilago kameruniensis).
- Clone 13: resistant to white mould disease. It is a high yielder, but its thin stems make it difficult to establish. It is also susceptible to Napier grass head smut disease.
- Kakamega 1 and 2: varieties are both tolerant to Napier grass head smut disease and are high yielders. Kakamega1 has a higher growth rate than Kakamega2 or Bana
- French Cameroon: A high yielder, established easily from canes. Susceptible to Napier grass head smut disease.
- Pakistan Hybrid: Does well in drier areas.
- Panicum Mombasa, which is good in biomass and thus silage making
Napier grass is Propagated vegetatively using splits or canes as the planting material.
- Canes (Stem cuttings):
- select fully mature stems from plants about to flower where the stems are still green (mention any characteristics to look out in a good planting material)
- cut stems into 30 cm (1 ft) long pieces with three nodes.
- Splits: A mature stool of Napier grass is cut back to 10-15 cm height, then part of the stool is dug out and divided into rooted splits for planting.
Benefits of using splits
- result in quicker establishment
- early first harvest than where cuttings are used.
Whether root splits or canes are used, they should be sufficiently mature to tiller well and produce tall and high yielding forage plants.
Why seeds are not used
- Napier is cross-pollinated, therefore plants produced in this way will not be uniform and their performance not predictable.
- seeds often germinate poorly and seedlings are weak.
- poor seed-setting and shattering makes seed non-availablec.
Planting
The canes or splits should be planted when there is adequate moisture in the soil, preferably during the onset of the rains.
Napier grass can be planted as Pure stand or Along contours and boundaries. The material is planted 15-20 cm deep with splits planted upright, three node canes planted at an angle of 30-45o while whole canes are buried in the furrow 60-90 cm apart.
Pure stand: Napier grass may be established as a pure stand where land is available; the plot will be used for bulking (to provide planting material to other farmers); and the farmer plans to intercrop with legumes in future.
Along contours and boundaries: Napier grass may be grown along contours or boundaries where land is sloping and a farmer wants to use it for soil conservation; and land is limited so the farmer cannot set aside land for growing Napier alone.
Spacing varies depending on the annual rainfall of the area; usually the higher the rainfall the closer the spacing. Root splits and canes are usually spaced at:
• 50 - 60 cm x 50 - 60 cm in areas receiving rainfall of above 1800mm per year.
• 50 - 60cm x 90 - 100 cm in areas receiving 900 – 1800 mm of rainfall per year,
• 90 - 100 cm x 90 -100cm in low rainfall areas receiving 700 - 900 mm of rainfall.
Establishing napier grass can also be through the conventional method or by using the Tumbukiza method.
Establishing (Planting) Napier grass through the Conventional Method
The conventional method involves planting one cane (with 3–4 nodes) or root split in holes 15–30cm deep. The spacing is 0.5m x 0.5m in areas with over 1400 mm of rainfall. In areas with 950–1400 mm rainfall the spacing is 1m x 0.5m. When cane cuttings are used, bury the nodes, leaving one node above the soil surface.
Planting using canes: Cane cuttings are pushed into the soil at a 45 degrees angle to the ground. Bury two nodes and leave one above the ground. Ensure the nodes face upwards.
Planting using splits: Planting holes are dug to a depth of 15-20 cm. Di-ammonium phosphate (DAP) fertilizer is then placed in the holes as specified in the section on Fertilizer/Manure application.
Spacing: The splits or cuttings are spaced at 50 x 100 cm. This close spacing is recommended for faster ground cover.
Establishing Napier grass through the Tumbukiza method
“Tumbukiza” is a method where the planting is done in round or rectangular pits of 60 cm wide diameter and 60 cm deep, filled with a mixture of topsoil and manure in the ratio of 1:2. Dig round pits 60 cm wide and 60 cm deep, with 60 cm between the rows or rectangular pits 60 cm deep, 60 – 90 cm wide and 90 cm long depending on moisture regime.
Tumbukiza pits for improved Napier grass productivity
- Separate topsoil (approximately top 15 cm) from subsoil.
- Mix 1 debe (20 litre tin) of topsoil with 1–2 debes of FYM and put into the pit. Plant 5–10 cane cuttings or root splits in round pits. In rectangular pits, plant 5–10 cuttings or root splits for every 90 cm pit. Leave about 15 cm unfilled space at the top (brim) of each hole. This method is recommended for the relatively dry areas.
• Land preparation: Dig pits measuring 60 cm (2 ft) square and 60 cm deep. Pits should be spaced such that the centres of each pair of pits are 100 cm apart.
• Fertilizer application: Mix one 20-litre container-full of top-soil with two 20-litre container-full of farmyard manure and put into the pits. This is equivalent to a ratio of 1:1 on weight basis since dry manure is lighter than soil.
• Planting: Plant 5-10 cane cuttings or a single rooted split per pit.
• Weed control: Hand weed when necessary.
• Top-dressing: Apply CAN, farm yard manure or slurry as recommended for the conventional method.
piglets.
The rate of fertilization varies with the soil and is dependent on the existing fertility level.
Four fertilizer and manure management practices are recommended for Napier grass. The choice depends on the financial resources of the farmer.
- Use 1–2 bags of 50 kg TSP (Triple Super Phosphate) or DAP fertilizer per hectare at planting followed by 5–7 bags of fertilizer in three split applications per year, applied after harvesting and weeding in subsequent years.
- 10t/ha of farmyard manure at planting. In the following years apply the same amount, preferably after every onset of long and short rainy seasons. If possible, analyze the manure for quality.
- Use ½–1 bag of 50 kg TSP (Triple Super Phosphate) or DAP plus 5 t/ha farmyard manure at planting. Additionally, apply 2–3 bags of 50kg CAN or Urea in three split applications per year in subsequent years.
- Apply 60 kg (litres) of liquid slurry (approximately 3 buckets of 20 litres) in furrows at planting followed by split application of the same quantity twice a year or more frequently if possible after harvesting.
- Where splits are used, place one tea spoon-full of Di-ammonium phosphate (DAP) fertilizer (5 g/plant or 100 kg DAP /ha) in the hole during planting, when there is adequate soil moisture. Separate fertilizer from the vegetative propagated stem cuttings with a layer of soil to avoid scorching of the roots.
- Where cane cuttings are used, or if there is no adequate moisture at the time of planting splits, DAP application is done one week after sprouting by placing the fertilizer about 10-15 cm away from the plant. t.
Napier grass can be intercropped with forage legumes in both methods of planting to improve the quality of the feed and reduce the cost of nitrogen fertilizer. Legumes that can be intercropped with Napier grass include Desmodium species (green leaf and Silver leaf), Lablab, Siratro, butterfly pea, vetch, centro and glycine. The legumes also help to control weeds and contribute to increasing herbage production, without competing wit the grass.
Napier grass intercropped with Desmodium species
When intercropping under the conventional method, make furrows along the Napier grass lines or in between rows and drill desmodium seed at a seed rate of 1-1.5 kg/acre, mixed with 10-25 kg TSP fertilizer/acre. For the tumbukiza method, drill desmodium seed in between the tumbukiza holes.
Napier grass requires regular and timely weeding to maintain high productivity.
Weed after each harvest. Harvest when 1 m high or every 6–8 weeks to obtain optimal quality and quantity. Maintain a stubble height of 5–10 cm from the ground level at each harvest to avoid weakening the root system, which leads to low production in subsequent harvests. To increase yields during the dry season, one of the split applications of the recommended rate of N fertilizer should be done 1–2 months before the end of the rainy season.
Major diseases (in Western Kenya) include Napier stunting disease which results in severe yield losses.
New varieties of Napier grass such as Ouma, South Africa and the new improved ILRI accessions have been found to be tolerant to the Napier stunting disease. Snow mould fungal disease is common to all Napier grass varieties except Clone 13. However, this disease is not a threat to herbage production. Pests are not a problem to Napier grass production.
Napier grass has also been identified as an important tool in the integrated management of stem borers of maize and sorghum due to its importance as a trap crop for these pests.
Push and Pull Technology, where maize is intercropped with Desmodium species and Napier grass plant around to control stem borers.
Harvesting should coincide with the timing of high forage quality.
Napier grass is very palatable to animals at the early leafy stage but not much liked after stem development. The crop is ready for harvesting 3–4 months after planting and harvesting can continue at an interval of 6–8 weeks for 3–5 years. Harvest when the Napier in 1m high. When harvesting, leave a stem length of 10 cm from the ground at harvesting.
Harvesting of Napier grass has been mostly carried out manually by smallholders. A silage chopper or some modification may be suited for mechanical harvesting.
Yield estimates vary depending on the climate, soil, cultivar and management.
Yields depend on agro-ecological zone and management but on average Napier grass can give 12 to 25 tons/ha of dry matter yield. Under optimal management practices Napier grass can give yields 40 t/ha/year in high rainfall (1200 mm to 2400 mm of rainfall).
Napier grass in terms of nutritional composition, depending on variety, contains 80-90% dry matter (DM), with a dry matter digestibility (DMD) of 60-65%; crude content (CP) content of 7.5-9.5% and metabolizable energy (ME) content of 8-10 MJ/kgDM. The crude protein content of Napier grass is below the recommended 16% for milk production by dairy cows. Hence, it is important to combine with other protein sources from forage legumes and improved fodders like forage sorghum to improve the nutritional value and digestibility. One acre of Napier grass planted by the conventional method can give enough feed for 1–2 dairy cows for one year. One acre of Napier grass planted by the tumbukiza method can give enough feed for 2–3 dairy cows for one year.
Napier grass is principally used for cut-and carry fodder for animals.
When harvesting Napier grass, leave a stem length of 4 inches (10 cm) from the ground at harvesting. When intercropped with Desmodium, harvest at 2-3 feet (60-90 cm) high. Chop the harvested Napier grass and Desmodium to reduce wastage while feeding it to the animals. Regrowth can be harvested when it reaches 2-3 feet (60-90 cm) high which means a period of 6-8 weeks between cuts. Do not graze animals directly on Napier grass. Feed 70 kg or 7 head loads of fresh Napier grass to a dairy cow per day. One acre of Napier grass planted by the conventional method can give enough feed for 1 to 2 dairy cows for one year. One acre of Napier grass planted by the Tumbukiza method can give enough feed for 2 to 3 dairy cows for one year.
Excess green feed can be preserved in the form of hay or silage for dry season feeding (Refer to Feed Conservation Module available in KALRO GAP APPs).
- Smallholder dairy farmer training manual. ILRI/GIZ Manual 24. Editors: J. P. Goopy, J. K. Gakige (Mazingira Centre, International Livestock Research Institute, Nairobi, Kenya). 2nd Edition
- Mutwedu, V.B., Manyawu, G.J., Lukuyu, M.N. and Bacigale, S. 2020. Fodder production manual for extension staff and farmers in South Kivu and Tanganyika Provinces of the Democratic Republic of the Congo. ILRI Manual 37. Nairobi, Kenya: International Livestock Research Institute (ILRI)
Kabirizi, J.; Muyekho, F.; Mulaa, M; Ajanga, S.; Zziwa, E.; G.; Mugerwa, S;. Lukwago, G.; Kariuki, I.; Atuhairwe, A.; Awalla, J.; Nampijja, Z.; Kawube, G.; Namazzi, C. 2015. Enhancing adoption of Napier grass and alternative fodder grasses resistant/tolerant to stunt and smut diseases for increased feed availability in smallholder systems in Eastern and Central Africa.