Summer Forage Crops -
Millets andLegume
Forage Millets
The millets provide growers with some useful summer forage crop options. While they are more demanding in their growing conditions and do not produce the same quantity of feed as the forage sorghums, they do have some other distinct advantages:
- Fill feed gaps during late both spring and autumn
- Feed quality is often higher than the forage sorghums, with no risk of prussic acid poisoning
- Supplementation with sulfur and salt blocks is not required
- Millet is one of the few summer forages suitable for horses, because of its lack of prussic acid.
Most cropping soils are suitable for millets, but because of the small seed, establishment is usually more reliable on the lighter loam and clay soils than on heavy clays or hard setting soils.
Grain millets
Cultivars in this group have physical attributes that make them unsuitable for grazing.
White French Millet (Panicum miliaceum)
The leaf and stems
are hairy, fibrous, and unpalatable to stock.
Dwarf Setaria/Foxtail Millets (Setaria italica)
The two main
varieties Panicum and Panorama are very quick maturing and do not
produce a great deal of dry matter. The stubble does however make good hay after
grain harvest.
Dual purpose millets
Japanese millet (Echinochloa esculenta)
The main advantage over
other forages is its ability to provide quick feed in spring. Japanese millet
has superior cold tolerance to the other millets and forage sorghums, and this
often enables it to be sown earlier in spring.
Rapid early growth under favourable conditions will usually allow grazing 4-6 weeks after planting; ideally when the crop is 25-40cm high.
While feed quality is high, quick maturity and relatively poor recovery from grazing usually means that Japanese millet yield is lower than for the other summer forage crops.
Japanese millet has better waterlogging tolerance than the other millets, and can be successfully grown under flood irrigation.
There are two varieties: Japanese and Shirohie
Siberian millet/White panicum (Echinochloa
frumentacae)
Siberian millet has a semi-prostrate growth habit, and
tillers profusely. While it is slower growing than the Japanese millets, it is
very palatable and does have a longer growing season and a better regrowth
potential after grazing. It is not as cold tolerant as Japanese millets.
Forage pennisetum/Pearl millet(Pennisetum
glaucum)
Because of their long growing season and superior recovery
from grazing, the forage pennisetums have the potential to outyield the Japanese
and Siberian millets. Under ideal conditions, forage pennisetum yields may also
approach those of the forage sorghums, but without the risk of prussic acid
poisoning. They are also more drought tolerant than the other millets.
Forage pennisetums are very demanding in the growing conditions however, and should only be considered where these specific requirements can be met:
- Need well drained soils, as they have no tolerance of waterlogging.
- Establishment is often unreliable. Avoid planting if cold or waterlogged conditions are likely to occur. Heavy clay soils should also be avoided (eg. some box soils).
- Need relatively high ground temperatures for establishment - preferably above 18° C and rising.
- Early growth is slow. The bulk of their growth is during summer and early autumn.
Open pollinated types
Katherine pearl millet is a late flowering,
tall cultivar, with dark green hairy leaves and the only one that is still
commercially available.
Hybrids
Justleaf® millet (an Aventis product)
Nutrifeed® (a Pacific Seeds product)
Both are ultra late maturing cultivars that grow between 1 and 2 metres in height if allowed to mature. The ultra-late flowering mechanism means they are easy to manage in a grazing situation and provide good quality leafier feed late in the season.
Planting information - Millets
Sowing time
All millets are damaged by frost, but Japanese millet
is more cold tolerant and can be sown when the risk of frost is over and the
soil temperature is 14 to 16° C and rising. Siberian millet and forage
pennisetum depend on warm soil for good growth and should not be sown until the
soil temperature has reached 18° C and is rising, (with a sowing window
October-January).
A well prepared, level seedbed is normally required for good germination. Millet are only small seeded and should only be sown 15-30 mm deep into good soil moisture. Rolling is an advantage is many situations. Avoid heavy clay soils, or soils prone to crusting.
Sowing rates
Japanese millets 8-10 kg/ha
Siberian millet 8-10
kg/ha
Open pollinated pearl millet 8-12 kg/ha
Hybrid pearl millet 4-8
kg/ha
The above seeding rates may be increased by 50-100% under irrigation.
Row spacing
Reduce row spacings to as narrow as possible for
Japanese and Siberian millets.
Weed control - Millets
2,4-D amine (500 g/L product) and fluroxypyr (Starane®) are both registered for the post-emergent control of broadleaf weeds in millet. The crop will need to have secondary roots established at the time of spraying or serious damage can result. MCPA and 2,4-D can both be very damaging to the crop, and growers are advised to consult with an agronomist before spraying with these products.
Crop nutrition - Millets
Millets respond to good nutrition and will grow well on a wide range of soils provided they are fertile or fertiliser has been applied at rates indicated from previous experience or by a soil analysis report.
Nitrogen
Pre-plant applications at 30 to 50 kg N/ha depending in
the cropping history of the paddock. This may need to be increased up to 60 to
80 kg N/ha under irrigation. Top dressing with up to 50 kg N/ha after intensive
grazing may be warranted where there is potential for significant regrowth (in
irrigated or good rainfall situations).
Phosphorus, zinc and potash
May also require attention to obtain
good crop growth.
Insect control - millets
While serious insect pests are not generally considered a routine problem, millets should be monitored for heliothis, cutworms, armyworms, locusts and shoot fly. These insects can occasionally reach damaging levels, and are controlled by the same chemicals used for other summer grain crops.
Grazing Management - Millets
Millets should not be grazed until they have well developed secondary roots and won't be pulled out. It is important to feed them off relatively early before the plants get too high. Feeding should generally commence when the crop is around 30-80cm high. This stage is usually reached 5-7 weeks after planting. For best regrowth, do not graze lower than 15cm or recovery will be very slow. Rotational grazing is preferred for better utilisation of the feed.
Carrying capacity
Up to three grazings are possible on irrigation,
while dryland crops usually enable two to three grazings. Stock carrying
capacities vary, although you can generally budget on 0.4-0.6ha of millet per
head (approximately two steers per hectare).
Weight gains on summer crops are not as high as on winter crops such as oats. A guide to livestock weight gains per head would be:
- Japanese and Siberian - 0.9kg/head/day
- Pearl millet - 0.8kg/head/day
- Forage sorghums - 0.7kg/head/day.
Weight gains per head will usually be higher on millet than on sorghum, although weight gains per hectare will be higher on sorghum because of its longer growing season and greater dry matter production.
Palatability
Palatability problems may occur with the
pearl millets under conditions of severe moisture stress.
Even under severe moisture stress, pearl millets may not show many outward signs of stress apart from a slowing in growth rate. Plants may remain relatively green and fresh looking, even when soil moisture us depleted and the crop is, in fact, under severe stress. By comparison, a forage sorghum crop under similar stress may show many outward signs such as leaf curling, leaf death and a blue-green plant colour.
Despite the lack of visible stress symptoms in forage pennisetums, they do suffer from severe moisture stress. This can significantly effect the palatability of the forage.
Soil Factors
If Nitrate N levels are higher than Phosphorus (as
determined by a Bicarb P test) unpalatability is more likely, when combined with
severe moisture stress, Conversely, if P levels are higher than N levels then
unpalatability is less likely.
What Restores Palatability?
In the event of a crop becoming
unpalatable, the only proven cure is a significant fall of rain (i.e. a drought
breaking rain) or irrigation.
The crop should become palatable within ten days after such rain provided it falls in the growing season and plants are able to resume growing.
Unfortunately no other attempted method of reversing the situation has provided consistent results.
Forage Legumes
Cowpea and lablab are summer forage legumes that can provide high quality feed to grazing animals in summer and autumn. This is particularly important in autumn when the feed quality of mature pasture and other forages can be low.
Soybean can usually equal the forage yield of cowpea and lablab but can only be used once as it recovers poorly after grazing or cutting. Soybean is not commonly sown as a forage crop in the region, however failed soybean grain crops are often salvaged as forage. Soybean is well adapted to the heavier clay soils in the higher rainfall or irrigated areas.
Cowpea
Red Caloona is the main variety because it has some resistance to the disease phytophthora root rot.
Ebony is a PBR variety available through Heritage Seeds. It is reported to have similar resistance to phytophthora as Red Caloona.
Lablab
Rongai
Late flowering, long season annual variety with white
flowers and tan seed.
Highworth
Late flowering, annual type with mauve flowers and black
seeds. Will not normally produce harvestable grain in S-Qld because of our
'shorter' summer season.
Orion
Is a reselected variety from Highworth and has similar growth
characteristics. It is a white seeded annual with mauve flowers. Contact Arnold
Kajewski regarding seed supplies (Ph 0749 846 146).
Koala
Erect annual type that is early flowering and early maturing
in S-Qld. It is suitable for grain production and/or grazing. Forage yields are
approximately 70% of Highworth because of its early maturity. Seed is white in
colour and flowers mauve. Koala is registered under PBR to Mt Tyson Seeds (Ph
0746 937 166).
Endurance
Perennial lablab suitable for short term fodder leys of
2-4 years duration. Bred by CSIRO and available from Selected Seeds under PBR
legislation (Ph 0746 931 800). Endurance has white flowers and tan seed.
Soybean
Long season varieties are generally preferred when planting under irrigation or favourable growing conditions. Select varieties with some phytophthora root-rot resistance when planting on heavy black clays with a history of soybean production.
Sowing information - Forage legumes
For reliable dryland production, the soil profile should be wet to a minimum depth of 1 metre at sowing.
Forage legumes can be sown after ground temperatures exceed 16° C and the risk of late frost is passed. October-January on the downs.
Recommended seeding rates (kg/ha), and inoculum type
|
Legume |
Seeding rate |
Inoculant |
|
Cowpea |
10-20 |
Group I |
|
Soybean |
50-70 |
Group H |
|
Lablab (annuals) |
10-25 |
Group J |
|
Lablab (perennial) |
16-25 |
Group J |
Crop nutrition - Forage legumes
Phosphorus, zinc, sulphur, and potash nutrition should be assessed. Sulphur and potash deficiencies are more likely to occur in double-crop situations. Fertiliser use should be based on previous experience and/or soil tests.
Weed control - Forage legumes
Wide row spacing (70-100cm) and interrow cultivation can provide effective weed control.
Trifluralin applied to bare soil at 1.4-2.1 L/ha pre-planting, for the control of annual grasses and certain broadleaf weeds.
Grazing management - Forage legumes
Crops should be allowed to reach canopy closure and a height of 50cm before grazing. Lablab bean is later to mature than cowpea or soybean and usually produces more bulk. It is also later to feed (cowpea and soybean 10-12 weeks; lablab, 12-14 weeks).
Cowpea gives better production if grazing is delayed until flowering.
Soybean regrows poorly after grazing, so delay grazing as long as possible (just before pods are half filled). This is the recommended stage for cutting for hay/silage.
Heavy prolonged grazing should be avoided. Best results are obtained if stock are removed before stems are damaged (ie. as soon as the leafy portion of the plants has been eaten).
Do not grazed or cut lablab and cowpea lower than 15cm if recovery is required. Grazing or cutting the crop lower than 15cm will kill many plants, thus lowering plant density and production.
Number of grazings will depend on time of sowing, seasonal conditions and grazing management. Lablab can be grazed up to 3 times, cowpea usually 2-3 times, and soybean once.
Strip grazing will help to obtain more efficient use of forage.
Animal Production - Forage legumes
Animals appear to scour less on lablab than cowpea. Cattle should be vaccinated against pulpy kidney with '5 in 1' if placed on lush forage crops. Bloat is rare, but has been recorded, so hungry stock should not be grazed directly onto forage legumes without allowing them to fill up on hay or roughage first. Cowpea can cause photosensitivity around the face and ears in sheep, particularly crossbred lambs, but this is not considered a major or regular problem. Soybean hay damaged by wet weather should not be fed to sheep because it may contain toxins from the fungus Phomopsis.
Hay production - Forage legumes
Cowpea, lablab and soybean make hay that compares favourably with lucerne. They should be cut at a time similar to that when ready for grazing. Unlike lucerne, these forage legumes will not recover after being cut back close to ground level.
Table 7 Average nutritive value of legume hay
|
Hay |
Dry matter % (DM) |
Crude protein % (DM) |
ME (MJ/kg DM) |
|
Lucerne |
90 |
15 - 20 |
8 - 10 |
|
Cowpea |
90 |
16 |
9 |
|
Lablab |
90 |
15 |
9 |
|
Soybean |
90 |
17 |
8 - 9 |
Silage - Forage legumes
Cowpea, lablab bean, and soybean can produce good quality silage, particularly if mixed with half or less the normal sowing rate of forage sorghum or millet.
All forage legumes have very low soluble sugar levels in their foliage, which can prevent good silage fermentation. Mowing and wilting cut material to 30-35% dry matter, 18-24 hours before ensiling will allow the concentration of soluble sugars in the plants to increase and improve the silage fermentation process. Forage mixtures will also benefit from wilting before ensiling.
For good quality hay or silage, cowpea is best cut around mid-flowering, while lablab can be cut any time after 12 weeks growth. Cut soybean before the pods are half filled.
Publications
Forage sorghum and millets:
· The Forage Book, Stuart, P.N., (Ed) (1993), Pacific Seeds.
Acknowledgment
This DPI Note is based on the corresponding chapter from the Darling Downs Summer Crop Management Notes book, a publication of DPI Farming Systems Institute.
More information
For more information on this topic, please see the following document:
Further information
- DPI Customer Service Centre 8.00 a.m. to 6.00 p.m. weekdays: Phone 13 25 23 (Queensland residents); non-Queensland residents phone (07) 3404 6999
- DPI's Farming Systems Institute website at http://www.dpi.qld.gov.au/fsi
- DPI's website at www.qld.gov.au
Information contained in this publication is provided as general advice only. For application to specific circumstances, professional advice should be sought. The Department of Primary Industries Queensland has taken all reasonable steps to ensure the information in this publication is accurate at the time of publication. Readers should ensure that they make appropriate inquiries to determine whether new information is available on the particular subject matter.
File No: fs0263b . May2003 . Replaces: fs98263