Lespedeza cuneata (PROSEA)
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Introduction |
Lespedeza cuneata (Dumont de Courset) G. Don
- Protologue: Gen. syst. 2: 307 (1832).
- Family: Leguminosae - Papilionoideae
- Chromosome number: 2n= 18, 20
Synonyms
- Hedysarum sericeum Thunb. ex Murray (1784),
- Anthyllis cuneata Dumont de Courset (1811),
- Lespedeza sericea (Thunb. ex Murray) Miquel (1867), non Benth. (1852).
Vernacular names
- Chinese lespedeza, sericea lespedeza, perennial lespedeza (En)
- Indonesia: lurampa ghaki
- Philippines: lalagim (Igorot).
Origin and geographic distribution
L. cuneata is indigenous to the Sino-Indian region of Asia and occurs naturally from Japan to Australia and from northern Pakistan and India to Taiwan. In Malesia, it is reported from Java, the Philippines, and Papua New Guinea. Introduced to the United States in 1896, it became naturalized in the south-eastern region. In the United States, it is cultivated eastward of 96°W between 30-40°N.
Uses
In the United States, L. cuneata is one of the most commonly used cover crops for planting on disturbed and eroding areas and on roadsides. In Japan, it is planted in mixtures with other species, also to control erosion of roadsides. It is often the first species planted when rehabilitating strip mine spoils. In the United States, it is grown as a non-bloating forage crop for grazing or hay. L. cuneata also has ornamental value.
Properties
Fresh forage of L. cuneata is generally of low palatibility and digestibility. Early work related this to a high tannin and lignin content and thick, coarse stems, but the factors affecting palatibility are not yet fully understood. Finer-stemmed cultivars, some of them also lower in tannin, have been developed. Preservation of forage as hay reduces tannin content and increases intake and digestibility in ruminants. The approximate average composition of hay per 100 g dry matter is: crude protein 15 g, fat 3 g, N-free extract 48 g, crude fibre 27 g, ash 6 g, P 0.2 g, K 1 g, Ca 1.5 g, Mg 0.2 g, Fe 30 mg, Mn 125 mg, carotene 4 mg, riboflavin 1 mg. Whole plants contain 5-8% tannin, leaves 7.5-18%; young plant parts contain less tannin than older ones. The weight of 1000 seeds is 1-2 g.
Description
- A deep rooting, erect, rarely semi-prostrate, short-lived perennial herb, 0.5-1 m tall, copiously branched. Stem striate, sparsely appressed-pilose on the ridges.
- Leaves alternate, trifoliolate; stipules lanceolate, 3-11 mm long, 3-veined; petiole 2-7 mm long; rachis 1-2 mm long; leaflets oblong-cuneate to linear-lanceolate, up to 3 cm × 0.5 cm, glabrous above, grey-green or silvery-silky beneath, margins slightly incurved.
- Inflorescence an axillary, 1-4-flowered fascicle; bracteoles 2; pedicel 1-2 mm long.
- Flowers chasmogamous or cleistogamous; chasmogamous flowers with sericeous calyx, tube 0.5-1 mm long, teeth 5, 3-5 mm long, petals white to cream, standard 6-9 mm long, 1-2 mm longer than keel and wings, purple-veined; cleistogamous flowers common, calyx sericeous, teeth 1.5-2 mm long, olive green to brown, corolla absent.
- Fruit an ovoid pod, 2.5-3 mm long, glabrous or appressed-pubescent, 1-seeded.
- Seed ovoid, 1.5-2 mm long, greenish-yellow with brown speckles.
Growth and development
Seedlings emerge 7-10 days after sowing under optimum conditions of temperature and adequate soil moisture. The optimum temperature for germination is about 30 °C; germination percentage is reduced to less than 70% at 15 °C and to less than 20% at 10 °C in most lines. Growth of seedlings and young plants is slow.
In the United States, crown buds appear below ground level toward the end of the season and remain dormant until spring. In spring, new stems arise from those buds as soon as the temperature rises. A late frost may kill the new spring growth, but plants are not severely affected and will regrow. Unlike many other legumes in the United States, L. cuneata will grow actively throughout the summer. In August, shoot growth decreases and nutrient reserves are built up in the taproot for winter storage. Flowering starts in early September. The relatively long growing period contributes to its persistence in plant mixtures.
Chasmogamous flowers are pollinated by several species of bees.
Other botanical information
Species of the genus Lespedeza Michx. are closely related to those of the genera Kummerowia Schindler and Campylotropis Bunge. They have all been included in Lespedeza in the past. However, Kummerowia has now been separated again, as no interspecific crosses have been obtained between species of Lespedeza and Kummerowia.
Pods of chasmogamous and cleistogamous flowers can be distinguished; those of chasmogamous flowers have a persistent style, those of cleistogamous flowers are blunt and rounded. Commercial cultivars in the United States can be grouped according to their tannin content. High in tannin are "Appalow", "Interstate", "Interstate 76", "Serala", and "Serala 76". Low in tannin are "AU Donnelly" and "AU Lotan". "AU Lotan", "Interstate 76" and "Serala 76" are tolerant of some nematode species, making them more persistent on light, nematode-infested soils. "AU Donelly" is resistant to Rhizoctonia spp.
Ecology
L. cuneata is adapted to tropical, subtropical and warm temperate areas with mean annual temperatures ranging from 10-29 °C. It tolerates drought, high levels of aluminium, and low soil fertility. In the Philippines it occurs on grassy slopes, from 1200-2200 m altitude; in Taiwan it is common in open locations (roadsides, waste land, hill sides) up to 3100 m altitude.
Daylengths of 13 hours or less are required for L. cuneata to flower. Daylength and temperature also strongly influence the proportion of chasmogamous and cleistogamous flowers produced and the seed produced from them; short daylength and low temperature favour the production of seed from cleistogamous flowers. Although a pH of 5.8-6.5 is recommended, L. cuneata tolerates acid soils, including acid subsoils of pH 4. In high pH (8.0) soils, plants will not survive for more than 2 years. The phosphorus requirements of L. cuneata are low compared to those of other forage species.
Propagation and planting
L. cuneata is propagated by seed. Mature seed is hard and needs to be scarified to germinate. Seed is placed at about 0.5 cm depth by broadcasting. Deep sowing will reduce emergence, but will not affect seedling vigour. Seed rate is 15-20 kg/ha when a herbicide is used, otherwise it should be increased to 20-30 kg/ha. L. cuneata is commonly grown as a sole crop; it is sometimes oversown with annual grasses to increase productivity. In the United States, L. cuneata is sown in early spring as soon as there is no risk of a severe frost.
Husbandry
Seedlings are extremely slow to establish and are poor competitors with weeds, so weeding or the application of herbicides is essential for establishment. After the first year and with good management, it is highly competitive with weeds. Stands of L. cuneata are severely reduced when grown on poor soils and cut more than twice per year. However, on fertile soils, up to 3 cuts can be done. It is sensitive to being cut back to less than 4 cm, especially when more than 2 or 3 cuts per year are made. When harvested for hay, plants should be cut when stems are 30-35 cm tall, leaving 8-13 cm stubble. Grazing should begin when plants are 20-25 cm tall to avoid close grazing and stand reduction. Although L. cuneata fixes atmospheric nitrogen, this does not become readily available to companion crops. In the autumn, the above-ground growth becomes woody litter, which decomposes very slowly and accumulates on the soil surface. When fertility of degraded soils has improved sufficiently, L. cuneata can be replaced by more productive crops. Eradication can be achieved by increasing the cutting intensity, followed by light disking and then sowing a fast-growing annual crop. The procedure often has to be repeated the following year.
Diseases and pests
L. cuneata does not have any major disease or insect pest problems. Some low-tannin genotypes are highly susceptible to a foliar disease caused by Rhizoctonia sp., but all cultivars released in the United States are resistant or tolerant. Root-knot nematodes can be a pest on light soils. Dodder (Cuscuta campestris Yunck.), a parasitic weed, can be a problem and should be eliminated immediately before it produces seed.
Harvesting
Forage cut for hay in favourable weather cures rapidly and must be carefully handled to reduce leaf losses. Hay can be baled 1 day after cutting.
Yield
Hay yields range from 5-8(-11) t/ha in the United States. Steers fed on L. cuneata pastures have achieved an average daily weight gain of 660-800 g. Seed yields average 350-1000 kg/ha.
Genetic resources
There is a great need to collect germplasm of L. cuneata. The United States Germplasm System holds only 46 accessions, 23 of which are from Japan. Most of the accessions are of limited agronomic potential. Other collections also hold only a few accessions.
Breeding
A programme to select genotypes tolerant of frequent clipping and to improve the grazing quality of older crops has been started at Auburn University, Alabama, United States.
Prospects
Its tolerance for poor, acid soils with high aluminium and low phosphorus levels and its persistence in mixed stands make L. cuneata a potentially useful cover crop for tropical highlands. It is one of the best plants for the warmer parts of the United States to rehabilitate seriously degraded land and to grow in low-input systems, because of its adaptation to marginal soils, low fertilizer requirements, high production of organic matter, and ability to fix atmospheric nitrogen. It may be useful in pasture renovation, but more research is needed on its establishment and management in grass sods.
Literature
- Dove, D., Wolf, D. & Zipper, C., 1991. Conversion of sericea lespedeza-dominant vegetation to quality forages for livestock use. Powell River Project Series, Publication 460-119. 6 pp.
- Henson, P.R. (Editor), 1957. The lespedezas. Advances in Agronomy 9: 113-157.
- Kalburtji, K.L. & Mosjidis, J.A., 1993. Effects of sericea lespedeza root exudates on some perennial grasses. Journal of Range Management 46: 312-315.
- Kalburtji, K.L. & Mosjidis, J.A., 1993. Effects of sericea lespedeza residues on cool-season grasses. Journal of Range Management 46: 315-319.
- Mkhatshwa, P.D. & Hoveland, C.S., 1991. Sericea lespedeza production on acid soils in Swaziland. Tropical Grasslands 25: 337-341.
- Mosjidis, C.O'H., Peterson, C.M. & Mosjidis, J.A., 1990. Developmental differences in the location of polyphenols and condensed tannins in the leaves and stems of sericea lespedeza, Lespedeza cuneata. Annals of Botany 65: 355-360.
- Mosjidis, J.A., 1990. Daylength and temperature effects on emergence and early growth of sericea lespedeza. Agronomy Journal 82: 923-926.
- Qiu, J., Mosjidis, J.A. & Williams, J.C., 1995. Variability for temperature of germination in sericea lespedeza germplasm. Crop Science 35: 237-241.
Authors
- J.A. Mosjidis
