Part E - Sub clover varieties and their identification

Current sub clover varieties

Choosing a sub clover variety is a matter of matching a variety with the particular environment and paddock in which it will be grown. The following descriptions will assist growers to select the varieties best suited to their needs. See also Part F Choosing the right sub clover variety — by using data on the minimum annual rainfall for persistence (Table F1) and the annual isohyets (Figure F1), growers can determine the most appropriate variety and preferably mix of varieties for a particular location. Varieties suited to the various climatic zones are given in Table F2 (which follows the map in Figure F1).

All varieties in the ‘current’ list have low oestrogen levels. Current varieties are listed below in the order of the timing of their maturity:

1. Nungarin
2. Dalkeith
3. Urana
4. Seaton Park and
   Seaton Park LF
5. York
6. Trikkala
7. Riverina
8. Gosse
9. Napier
10. Rosedale
11. Junee
12. Coolamon
13. Woogenellup
14. Goulburn
15. Denmark
16. Leura
17. Clare
18. Antas
19. Nuba

See also the sub clover leaf identification chart for comparison of the leaves of current varieties.

1. Nungarin

Nungarin (Northam A2 × Daglish) was bred and selected by members of the National Subterranean Clover Improvement Programme (NSCIP), and released in 1977. It is the earliest maturing and one of the hardest seeded varieties available. Seed yields have been outstanding and the variety persists well over much of the sub clover belt in New South Wales. In all situations Nungarin has consistently done better than the high-oestrogen varieties Dwalganup and Geraldton. In particular, it has helped spread the sub clover belt westwards into areas which, though suited to sub clover, are too dry for Dwalganup or Geraldton to establish and grow reliably. Because of its earlier maturity, Nungarin does not produce much feed in late spring.

2. Dalkeith

Dalkeith is named after a Perth suburb, where it was discovered by Dr JS Gladstones in 1967. It was registered by NSW Agriculture in 1983. Dalkeith is a low-oestrogen, early variety of similar maturity to Dwalganup, but with a very high level of hard seed, similar to that of Nungarin. On the southern plains and the central slopes (around Dubbo), it has persisted better than all commercial varieties. The higher level of hard seed has been mainly responsible for this superiority. It enables a greater proportion of seed to survive for the true autumn start after the many summer storms and false starts that are typical of the central slopes. Dalkeith is more tolerant of bluegreen aphid than Daliak, but it is susceptible to clover scorch.

Dalkeith is suitable as the sub clover component in a pasture mix with lucerne. It is similar in appearance to Dwalganup. To ensure varietal purity, Dalkeith is grown for seed production under a pedigree seed scheme. In medium-rainfall areas Dalkeith is a useful, persistent component when in a mixture with a longer-season, less persistent (but more productive) variety.

3. Urana

Urana is an early-flowering crossbred variety released in 2002 by the National Annual Pasture Legume Improvement Program (NAPLIP) as a more productive alternative to Daliak. It has higher levels of hard seed than Dalkeith, low formononetin levels, and slightly better seedling and adult plant resistance to redlegged earth mites than existing cultivars. Being early maturing it is suited to low-rainfall areas of the wheatbelt. Urana is susceptible to race 1 of clover scorch disease but it should not be grown in higher-rainfall areas where the disease is common.

4. Seaton Park and Seaton Park (LF)

Seaton Park was collected in a suburb of Adelaide in 1941 but, like Daliak, only became prominent when it was found to be low in formononetin. Seaton Park was released in Western Australia in 1967. An early mid-season type, its maturity is midway between that of Daliak and Woogenellup, as is its level of hard seed.

Seaton Park is a very popular variety because it has a balance of desirable characteristics — good spring growth suitable for haymaking and a moderate level of hard seed for persistence.

Under favourable spring conditions, Seaton Park is only slightly less productive than Woogenellup. Under adverse conditions (either a dry spring or false autumn germinations), Seaton Park is more persistent than Woogenellup because of its earlier maturity and higher level of hard seed. Seaton Park is susceptible to clover scorch but has good tolerance to Phytophthora root rot.

Because the oestrogen levels were found to have risen in Seaton Park, it was reselected for low formonentin (LF) and renamed Seaton Park LF in 1994. Only the LF type should be sown.

5. York

This mid-season low-oestrogen variety was collected in Sardinia and registered by the Australasian Subterranean Clover and Alternative Legumes Improvement Program (ASCALIP) in 1995 as a hard-seeded alternative to Seaton Park LF. York has better resistance to the leaf disease powdery mildew and better resistance to the root disease Pythium (‘damping off’) and Rhizoctonia. It has a higher level of resistance to races 0 and 2 of Phytophthora root rot but is more susceptible to race 1 than is Seaton Park LF. For this reason it is best grown in a mixture with Riverina or Seaton Park LF in areas where Phytophthora is a problem. In other areas it is a good replacement for Seaton Park LF where increased resistance to powdery mildew and higher levels of hard seed are needed.

6. Trikkala

Released in 1976, Trikkala was developed jointly by the Western Australian Department of Agriculture and the University of Western Australia from a cross that Dr FHW Morley (CSIRO) made between Neuchatel, an early Yarloop mutant, and Larisa.

Like Yarloop, Trikkala belongs to the subspecies yanninicum. It tolerates shallow flooding and waterlogging, and matures by late October. Unlike Yarloop, Trikkala will not cause infertility in sheep.

Trikkala is suitable for sowing on irrigated paddocks and on floodplains and waterlogged areas. On irrigated sites the growth and seed yield of Trikkala are equal to Yarloop. But in some dryland conditions, Trikkala does not persist as well as Yarloop because of its low level of hard seed (similar to that of Woogenellup). In these situations, or where soil types and drainage are variable, a mixture of Riverina, Dalkeith, Seaton Park LF or Junee (depending on rainfall) will ensure a more uniformly persistent pasture. Trikkala has some tolerance of clover scorch and is resistant to races 0 and 2 of Phytophthora root rot, but not to the highly virulent race 1. (Riverina and Gosse are preferred where Phytophthora root rot is prevalent and where hardseededness is an advantage.)

7. Riverina

This large-seeded yanninicum variety was registered by ASCALIP* in 1995 to replace Trikkala. It resulted from a cross between Meteora and Trikkala. It has much higher levels of hard seed than Trikkala and superior resistance to Phytophthora root rot, having the highest level of resistance to the highly virulent race 1 of all registered varieties. Suitable for both dryland and irrigation areas, this variety tolerates winter waterlogging and has vigorous seedlings, good winter growth and an upright growth habit. It flowers about 5–7 days earlier than Gosse and matures slightly earlier. Riverina has superior resistance to Pythium root rot and has a higher level of tolerance to powdery mildew than Gosse but may show some symptoms under wet spring conditions. It is suitable for all areas where Trikkala is grown.

8. Gosse

This large-seeded variety was registered in 1992 by ASCALIP* as a more winter-productive replacement for Larisa. Gosse is a member of the yanninicum group and is very tolerant of waterlogging. It has greatly improved tolerance to clover scorch disease and a higher level of hard seed compared with Trikkala. It flowers up to 2 weeks later than Trikkala and therefore requires a longer growing season. Gosse is a good variety for irrigation areas, where its excellent winter vigour is a major advantage. Resistance to race 1 of Phytophthora is inferior to that of Riverina, but it has good resistance to race 0 and 2. It is more susceptible to Pythium and powdery mildew than either Riverina or Trikkala.

9. Napier

Napier is a new late-maturing large-seeded variety released by NAPLIP* as an alternative to Larisa and Meteora, having superior winter and spring productivity to the older varieties and superior seed yields. Being a member of the yanninicum subspecies, it is tolerant of waterlogged soils. It is more hard-seeded than Gosse, Riverina and Larisa. It has good resistance to both known races of clover scorch disease and to two major races of Phytophthora root rot. It has a low oestrogen content. Its main use is in soils prone to waterlogging and where the growing season is at least 7.5 months under irrigation. Its late maturity and erect habit make it particularly suitable for cattle grazing and for forage conservation.

10. Rosedale

The Rosedale variety was registered in 1988, and selected by P Beale of the South Australian Department of Agriculture from seed collected in Turkey in 1974 by CM Francis. A member of the brachycalycinum group, it is more prostrate and has smaller leaves than Clare. It is earlier maturing, flowering about 9 days earlier than Clare, and is more hard-seeded. It has good resistance to clover scorch disease but is very susceptible to all three races of Phytophthora root rot. Rosedale produces cream seed which is smaller than Clare. It is suited to heavy soils and can be grown with Clare where seasons are shorter or more variable.

11. Junee

Junee was released jointly in 1984 by the Western Australian Department of Agriculture and NSW Agriculture from a cross made at Perth between Daliak and H20 (Howard × Midland B). Junee was released as a more hard-seeded and clover-scorch-resistant alternative to Woogenellup.

Maturing slightly earlier than Woogenellup (2–3 days), Junee has a moderate level of hardseededness (similar to Seaton Park), good burr burial, resistance to clover scorch and some tolerance of the clover root rot complex. It is susceptible to powdery mildew disease. Experiments in southern and central NSW have shown Junee to be more persistent than Woogenellup and well suited to environments east of a line linking Corowa, Junee (the southern NSW town after which it was named), Wellington and Coonabarabran. It is suitable as an alternative to Woogenellup along the eastern fringe of the wheat belt and on the tablelands. Like Dalkeith, it is grown under a limited generation seed production scheme in NSW.

12. Coolamon

Coolamon was released in 2004 and is a mid-season variety. Coolamon derived from a cross with Junee. It was bred to be more erect and have a brighter leaf colour in winter — these characteristics were perceived to be limitations of Junee. In field trials, Coolamon has been, on average, 12% more productive than Junee in autumn–winter, and 16% more productive than Junee in spring.

Seedling regeneration is, on average, 12% higher than Junee. It is resistant to cercospora leaf spot. It is moderately susceptible to leaf rust and susceptible to powdery mildew but less so than Junee. It has improved resistance to race 2 of clover scorch.

Coolamon flowers at the same time as Junee and is moderately hard-seeded, with about 24% of the seed hard in the following autumn. Flowers are white with no red band. Stipules have red veins.

13. Woogenellup

Woogenellup was first recorded at Elgin in Western Australia. It was named in 1957 and later recognised to be almost identical to the variety Marrar found in 1955 near Wagga Wagga in NSW. Seed was certified in this state in 1960.

Sown over much of the sub clover area of NSW, this mid-season, soft-seeded variety has shown unsatisfactory persistence where droughts are common and where soil moisture is unavailable in late October and early November, or where the risk of frequent false autumn breaks is high. Because it does not persist well in some situations, it may have to be resown more frequently than varieties such as Seaton Park or Junee. Woogenellup was a popular variety for haymaking because of its erect growth habit and good spring production. However, it is highly susceptible to clover scorch and the root rot disease complex. In southern NSW it has been largely replaced by Goulburn, Junee and Riverina but is still useful in northern NSW because of its good seedling vigour and the apparent low incidence of root rot.

14. Goulburn

This variety was originally collected in Sardinia and was released by ASCALIP* in 1991 as a hard-seeded clover-scorch-resistant replacement for Woogenellup. This mid to late season variety also has significantly more tolerance to Phytophthora root rot race 0, which was the only race identified at the time of its release, but is susceptible to race 1. Winter and spring herbage of Goulburn is superior to that of Woogenellup, where root disease or clover scorch is present. Goulburn is small-seeded and produces higher densities of seedlings than Woogenellup. Goulburn also has good tolerance to leaf rust and powdery mildew and a high level of hard seed for its maturity. Because of its superior disease tolerance and higher levels of hard seed, Goulburn is far more persistent than Woogenellup.

15. Denmark

Denmark was registered by ASCALIP* as a replacement for Karridale and Mount Barker in 1991, and was originally collected in Sardinia. Its major advantages over Karridale are increased levels of resistance to clover scorch disease and better resistance to race 0 of Phytophthora root rot. This medium to late season cultivar is more productive than Mount Barker on the higher-rainfall areas of the slopes and tablelands. It has superior resistance to Pythium and clover scorch disease than both Karridale and Mount Barker, and tolerates a slightly shorter growing season than Leura.

16. Leura

This late-flowering cultivar collected in Sardinia was released by ASCALIP* in 1991 and is the first low-oestrogen long-season variety to replace the oestrogenic variety Tallarook. Being very late maturing, it makes better use of late-spring rainfall and is more productive than Denmark or Karridale when there is a very long growing season. It has superior resistance to leaf rust than Karridale, Denmark and Mount Barker, which can be a problem in higher-rainfall areas. It has good resistance to race 0 and 2 of Phytophthora root rot but is susceptible to race 1. Phytophthora root disease is not normally a problem in the higher-rainfall areas where Leura is suited. In field trials at Orange, Yass and Crookwell, Leura had greater winter production than Karridale and Goulburn, and was far superior in production compared with Mount Barker. It has very low levels of hard seed; however, this attribute is not important in the area in which it is grown. It is suited to the higher-rainfall areas of the tablelands.

17. Clare

Clare is a member of the species T. brachycalycinum. It was found at Clare in South Australia and has been certified in NSW since 1955. Clare has persisted and done well on the non-acid, red and black cracking soils of the higher-rainfall areas of the North Western Slopes. Although adapted to alkaline soils, it matures too late and its hard seeds break down too quickly for it to persist well on the drier western fringe of the northern clover belt, where soils are generally neutral to alkaline.

Clare grows vigorously during winter provided temperatures are mild, as it has some susceptibility to frost. This variety is used in some western irrigation areas and in coastal areas where it is sown at high seeding rates as a winter–spring forage crop. Clover disease is not a problem in sheep grazing on Clare. This variety is more resistant to rust than Mount Barker but is susceptible to clover scorch and to the sub clover root rot complex.

18. Antas

Antas is a large-seeded variety selected in Europe and is a member of the brachycalycinum subspecies adapted to neutral to alkaline soils. It is a late-maturing variety, flowering about 1 week later than Clare and hence requires a longer growing season. It has excellent winter and late-season productivity. It is more hard-seeded than Clare. It is susceptible to redlegged earth mite and slightly susceptible to clover scorch disease. Its erect growth habit and good spring productivity make it suitable for hay and silage production. It has moderate resistance to Pythium and Fusarium.

19. Nuba

A large-seeded, very late maturing brachycalycinum variety bred in Germany from a cross between Clare and a Spanish ecotype. It was first registered in Australia in 1990. It is grown mostly as a cold-tolerant fodder plant in Europe. Nuba produces very large vigorous seedlings with large, tall leaves. If sown at a high seeding rate, it may be suitable as a highly productive 1-year fodder crop or for hay making. It is more susceptible to clover stunt virus than Clare. Nuba has not been selected for Australian conditions and is susceptible to clover scorch, Phytophthora root rot and leaf rust. However, under favourable conditions it can be very productive, particularly in winter, although persistence and regeneration can be poor.

Superseded, unobtainable or undesirable sub clover varieties

The varieties listed below have been superseded for most areas of NSW and/or have undesirable characteristics, such as:

• high formononetin levels which can cause clover disease in stock;
• poor persistence;
• low levels of hard seed;
• susceptible to disease or to attack by insects;
• unfavourable growth habit;
• lack of vigour;
• limited areas of suitability;
• seed unobtainable or in short supply.

These non-current varieties are listed below in the order of the timing of their maturity:

1. Dwalganup
2. Geraldton
3. Northam
4. Daliak
5. Dinninup
6. Enfield
7. Howard
8. Esperance
9. Green Range
10. Bacchus Marsh
11. Mount Barker
12. Uniwager
13. Nangeela
14. Karridale
15. Yarloop
16. Larisa
17. Meteora
18. Tallarook

1. Dwalganup

Reasons for non-inclusion in the 'current variety' list:

• Extremely high formononetin level.
• Can cause severe clover disease in sheep.

Dwalganup was the first early-maturing sub clover variety to be commercialised in Australia. A natural selection, it was known to farmers in Western Australia as early as 1900. It was first certified in NSW in 1952 but is no longer either certified or recommended in this state because of its extremely high formononetin level, which can cause severe clover disease in sheep. Dwalganup has been replaced by several varieties that do not cause clover disease, and which are more productive than Dwalganup in the areas where they are used. These varieties include Nungarin, Northam, Daliak, Dalkeith and, in higher-rainfall areas, Seaton Park. Often a contaminant of uncertified seed from Western Australia.

2. Geraldton

Reasons for non-inclusion in the 'current variety' list:

• High formononetin level.
• Capable of causing clover disease.
• Replaced by Nungarin and Northam.

Released commercially in 1959 by the University of Western Australia, Geraldton is an early-maturing variety. It does not perform as well as its replacements, Nungarin and Northam. Often a contaminant of uncertified seed from Western Australia.

3. Northam

Reasons for non-inclusion in the 'current variety' list:

• Slightly less persistent than Nungarin in dry areas.
• Seed softer than Nungarin.
• Seed is not readily available.

Northam is a natural selection, previously known as ‘Northam A’, from the town site of Northam in Western Australia. It is early flowering like Nungarin, but slightly later maturing and with softer seeds. Northam is also more erect and showy than Nungarin. Released in 1976 in Western Australia as a low-oestrogen replacement for Dwalganup and Geraldton, Northam has done better than these varieties, but it is slightly less persistent than Nungarin in dry areas. In most environments, however, Northam is suited to the same range of uses as Nungarin. Nungarin is superior in drier areas and Dalkeith more productive in the drier wheat belt. Seed is not readily available.

4. Daliak

Reasons for non-inclusion in the 'current variety' list:

• More susceptible than other varieties to attack by bluegreen aphid.
• Shorter compact growth habit.
• Superseded by Dalkeith.

A natural selection first observed near York in Western Australia in the late 1920s, Daliak did not become prominent until 1960 when it was found to be low in formononetin. It was released in Western Australia in 1967 and has been sown in NSW since 1970.

Daliak is a semi-erect, plain-leafed variety that produces well, and seeds prolifically throughout the sub clover belt. Due to its mid-season maturity it is more productive than the early-maturing Northam, Nungarin or Dalkeith, but less productive than later maturing varieties. Daliak is resistant to the eastern Australian strain of clover scorch and is tolerant of the sub clover root disease complex, but it is more susceptible than other varieties to attack by bluegreen aphid. It is not widely grown in NSW and is unpopular because of its shorter compact growth habit. This variety has been superseded by Dalkeith.

5. Dinninup

Reasons for non-inclusion in the 'current variety' list:

• Has a very high formononetin level.
• Will cause severe clover disease in sheep.

Dinninup is a mid-season variety. It has not been widely sown in NSW but, like Dwalganup and Geraldton, it is often a contaminant of uncertified seed from Western Australia.

6. Enfield

Reasons for non-inclusion in the 'current variety' list:

• Lack of hard seed.
• Susceptible to Phytophthora root rot.

Enfield is a natural strain collected by Mr GM Halloran in 1973 from a roadside near Kilmore, Victoria. It was submitted for registration by the Victorian Department of Agriculture in 1982. Developed as a clover-scorch-tolerant alternative to Woogenellup, Enfield is of similar maturity to Woogenellup. It sets a large number of small seeds, predominantly on the surface, that quickly become soft. This results in a very small carryover of seed from one year to the next. Its lack of hard seed (less hard seed than Mount Barker) severely limits its usefulness in NSW. Enfield is also susceptible to Phytophthora root rot.

7. Howard

Reasons for non-inclusion in the 'current variety' list:

• High formononetin level.
• Susceptible to clover scorch.
• Less productive than Woogenellup.

Of similar maturity to Woogenellup, Howard was bred for resistance to clover stunt virus. Unfortunately it has a high formononetin level and is susceptible to clover scorch.

8. Esperance

Reasons for non-inclusion in the 'current variety' list:

• Not suitable for haymaking because of its less erect growth habit.
• Seed is not readily available.

The variety Esperance, released in 1978, was selected specifically as a clover-scorch-resistant replacement for Woogenellup. A cross between Daliak and Bacchus Marsh, Esperance closely resembles Daliak except that it matures 3 weeks later (slightly shorter seasoned than Woogenellup), and has a less distinctive calyx colour.

Esperance has a level of hard seed that is higher than that of Woogenellup, but slightly lower than Seaton Park. It is also highly resistant to the eastern Australian strain of clover scorch and tolerant of the clover root rot complex. Compared with Woogenellup, Esperance is more persistent; but, because of its less erect growth habit, is not as suitable for haymaking. Seed is not readily available and it is no longer widely grown in NSW.

9. Green Range

Reasons for non-inclusion in the 'current variety' list:

• Extreme susceptibility to leaf rust.
• Lack of clear superiority over Junee and Woogenellup.

Green Range was released by the Western Australian Department of Agriculture in 1984 as a hard-seeded, clover-scorch-resistant replacement for Woogenellup. It is not recommended in NSW because of its extreme susceptibility to leaf rust and a lack of clear superiority over Junee and Woogenellup. Resistance to the eastern Australian strain of clover scorch and a slightly higher level of hard seed are the main advantages of Green Range.

10. Bacchus Marsh

Reasons for non-inclusion in the 'current variety' list:

• Low proportion of hard seed.
• Most burr forms on the soil surface.
• Susceptibility to clover stunt virus, root rots and clover scorch.

Bacchus Marsh, now an obsolete variety, originated in Victoria. In NSW, it is present in irrigation areas, on the tablelands and along the coast. It is adapted to similar environments to those that suit Mount Barker, and matures about 1 week later than Woogenellup, but is inferior to both these varieties. Bacchus Marsh does not cause clover disease.

11. Mount Barker

Reasons for non-inclusion in the 'current variety' list:

• Persistence poor on the slopes and plains.
• Susceptible to leaf rust and Phytophthora root rot.
• Superseded by Denmark and Leura.

Mount Barker was the first sub clover variety grown in Australia. It was found and developed in South Australia by Mr AW Howard of Mount Barker in South Australia after he recognised its potential as a pasture plant in 1889. Mount Barker has been sown in NSW since the mid-1920s, where it has always been a popular variety on the Southern and Central Tablelands. On the slopes and plains, where less rain falls, the persistence of Mount Barker has been poor.

Mount Barker is very low in formononetin, so is unlikely to cause clover disease. It is susceptible to leaf rust and Phytophthora root rot, but has some tolerance of clover scorch and is moderately resistant to clover stunt virus. This variety has now been superseded by Denmark and Leura, which are more productive.

12. Uniwager

Reason for non-inclusion in the 'current variety' list:

• Lacked the vigour of its parent Geraldton.

This variety is a chemically induced mutant of the cultivar Geraldton and was released in 1967. Although free of oestrogens, it lacked the vigour of its parent and was unpopular.

13. Nangeela

Reasons for non-inclusion in the 'current variety' list:

• Susceptible to clover scorch disease, Rhizoctonia and Fusarium ‘damping off’.
• Highly susceptible to bean yellow mosaic virus.
• Moderately susceptible to leaf rust.
• Soft-seeded.
• Goulburn, Denmark and Leura are superior cultivars.

Originated in Victoria where it was discovered in the early 1930s. It is late-maturing with a low oestrogen content.

14. Karridale

Reason for non-inclusion in the 'current variety' list:

• Superseded by Denmark.

Released in 1984, Karridale was developed under the NSCIP* as a disease-resistant alternative to Mount Barker. The origin of Karridale is uncertain, although it is thought to have originated as a Midland B / Nangeela / Dinninup cross.

Karridale has generally been the equal of, or superior to, Woogenellup and Mount Barker for seed yield and production of dry matter in areas of high rainfall. Karridale has good resistance to clover scorch, to the Pythium, Fusarium and Rhizoctonia root rots, and to races 0 and 2 of Phytophthora root rot. It also has better than average tolerance to redlegged earth mites and to clover redleaf virus. The hard-seed level is similar to that of Woogenellup but superior to Mount Barker, while burr burial is often superior. Karridale is of similar maturity to Mount Barker, flowering about 10 days later than Woogenellup. Karridale has been superseded by Denmark.

15. Yarloop

Reasons for non-inclusion in the 'current variety' list:

• Contains very high levels of formononetin.
• Will cause severe clover disease.
• On waterlogged and flooded soils, including soils under irrigation, Yarloop has been replaced by Trikkala, Gosse and Riverina.

Yarloop belongs to the subspecies yanninicum. This variety is a natural selection from Western Australia.

16. Larisa

Reasons for non-inclusion in the 'current variety' list:

• Low level of hard seed.
• Suited only to irrigation areas, or to dryland sowing in a very limited area of southern NSW that has reliable autumn–winter–spring moisture and annual rainfall over 800 mm.
• Superseded by Gosse, which has a superior winter vigour.

Larisa was selected at the University of Western Australia from varieties collected in northern Greece. This variety belongs to the yanninicum subspecies but matures about 6 weeks later than either Yarloop or Trikkala. It contains very low concentrations of harmful oestrogens and is less susceptible to clover scorch than Yarloop or Woogenellup. However, because of its low level of hard seed and later maturity, Larisa is suited only to irrigation or to dryland sowing in a very limited area of southern NSW that has reliable autumn–winter–spring moisture and annual rainfall over 800 mm. It has very good resistance to all root rots.

17. Meteora

Reasons for non-inclusion in the 'current variety' list:

• Suited only to areas of southern NSW with high and reliable rainfall in autumn, winter and spring.
• Replaced by Gosse.

Meteora is a late-maturing variety (9–10 days later than Mount Barker) and is a member of the subspecies yanninicum. It was selected from a damp location in Greece by Dr JS Katznelson. It was registered by the Western Australian Department of Agriculture and the University of Western Australia in 1981. Meteora is more tolerant of clover scorch than Trikkala and Larisa, but like Larisa (which matures slightly earlier), it is suited only to areas of southern NSW with high and reliable rainfall in autumn, winter and spring.

18. Tallarook

Reasons for non-inclusion in the 'current variety' list:

• High formononetin level.
• Susceptible to clover scorch.

Tallarook is a late-flowering variety, flowering about 1 month after Woogenellup. It is highly resistant to some strains of clover stunt virus. Because of its high formononetin level and susceptibility to clover scorch, it is not suitable for use in NSW.

Naturalised sub clover strains

There are many naturalised strains or ecotypes present throughout NSW. Two that have become prominent in the higher-rainfall areas of the South West Slopes are Book Book and Cookardinia. Both are named after the places where they were first observed, are of mid-season maturity and are highly oestrogenic.

Cookardinia has leaf markings similar to those of Bacchus Marsh. The characteristics of the stipule, flower and runner are similar to those of Mount Barker.

The leaf markings of Book Book are similar to those of Dwalganup, but the stipule, flower and runner resemble those of Mount Barker.

Descriptions of the 115 naturalised strains of subterranean clover identified in Western Australia are given in:

Gladstones, JS & Collins, WJ  Naturalised clover strains of Western Australia, Technical Bulletin No. 64, Department of Agriculture Western Australia.

Identifying sub clover varieties

Farmers should be able to identify sub clover varieties in order to monitor their paddocks for establishment and persistence of sown varieties and to detect any plants of oestrogenic varieties that cause clover disease, particularly Dwalganup and Yarloop.

Varieties are identified on the basis of variation in:

• leaf shape (see the leaf identification chart for current sub clover varieties)
• leaf marking
• hairiness
• colouring of plant parts.

The main botanical characteristics used to identify commercial varieties of sub clover are summarised in the identification key below. These characteristics are stable, but plants within the same variety can differ in minor ways depending on stage of:

• maturity
• climate
• soil fertility
• management
• diseases
• pests.

For this reason, the best time to identify varieties is at flowering.

Leaf marking

The pattern of the pale central mark or crescent on the upper leaf surface is a stable and reliable characteristic for each variety. This marking, which is in the centre of the leaf, is a light green colour. In some varieties it extends to the margin of the leaf. In addition, there may be white or pale green bands extending from the margin towards the centre of the leaf (see Figures E1 and E2).

In some varieties a brown anthocyanin pigment may be present either along the borders of the pale marking (e.g. Clare), along the lower midrib of the leaf (e.g. Yarloop), or as flecks (e.g. Bacchus Marsh). However, the extent of anthocyanin pigmentation depends on environmental influences such as low temperatures, so this feature is not a good guide.

Colour of the stipule

The stipule colour varies between varieties but is constant within any particular one. It varies in appearance from a greenish white with green or red veins to being red-veined and red banded (see Figure E1). Colouration will vary depending on the amount of light reaching the stipule.

Hairiness

The degree of hairiness on the runners of each variety is indicated in the identification key (Figure E2).

Flower

• Corolla colour. In commercial varieties the colour pattern of the corolla (petals) is either pure white or white with pink veins. The Dwalganup strain has a decidedly pink tinge when the petals are exposed to strong sunlight.
   
• Calyx colour. The colour pattern of the calyx of the flower varies from a striking red band (e.g. Daliak, Mount Barker) to an overall greenish white colour (e.g. Seaton Park, Woogenellup and Bacchus Marsh).

Flowering

Time from sowing to the start of flowering is a useful guide to the maturity group that a variety belongs to. The number of days to the commencement of flowering depends on the time of the year at which germination takes place, and on the temperature. The number of days to flowering decreases as the date of germination becomes later. The time for a cultivar to flower in Perth from a May sowing is the standard index used to classify the maturity of a variety. Comparable times to flowering at Wagga Wagga are also given in Table F1.

Relative maturity

The time that different varieties take from sowing to maturity (see Table F1) can help in identification, but is not completely reliable because there is substantial overlap.

Seed colour

The seeds of Yarloop, Trikkala, Riverina, Gosse, Meteora, Rosedale and Larisa are cream to light brown. All other varieties have black or purplish seeds.

Identification key

The plant parts used for identifying sub clover are shown in Figure E1:

Figure E1. Botanical characteristics of sub clover used in variety identification

Examine a whole plant, or at least one or two runners, from a typical plant. Then list the ratings for the plant’s botanical characteristics according to Figure E2:

Figure E2. Rating categories

Then compare your list of characteristics to the data in Table E1.

Leaf identification chart for current varieties

See the leaf identification chart for the following current varieties:

• Nungarin
• Dalkeith
• Urana
• Seaton Park
• York
• Trikkala
• Riverina
• Gosse
• Napier
• Rosedale
• Junee
• Coolamon
• Woogenellup
• Goulburn
• Denmark
• Leura
• Clare
• Nuba

Farmers who are interested in identifying sub clover varieties should obtain a copy of the printed 3rd edition of this publication, Subterranean clover in NSW — identification and use, from the NSW Agriculture Bookshop. It contains photographs of 33 sub clover varieties which will assist further in identification.

Further information

For further information on subterranean clover, see the other sections of this Agfact:

• Part A Subterranean clover in New South Wales - identification and use
• Part B Diseases of sub clover
• Part C Insect pests of sub clover
• Part D Viruses in sub clover
• Part F Choosing the right sub clover variety
• Part G Establishing sub clover

See also Agnote DPI-268 Subterranean clover (part of the Pasture Planner series).