Crimson clover (Trifolium incarnatum)

Plant description:

It has trifoliate leaves, with individual leaflets being relatively large, on average measuring 1-3 cm long and nearly as wide. Flowers are cylindrical in shape, measure up to 40 mm in length, and are generally bright red, though an occasional yellow or white flower may occur.

Where it grows:

Rainfall:

Crimson clover is generally suited to areas with >500 mm annual rainfall. However, its deep rooting habit may make it suitable to grow in areas with a perched water table and annual rainfall as low as 425 mm.

Soils:

Crimson clover grows on a range of soils with pH ranging from 4.5 - 8.0 (CaCl2)) and soil textures, but will not persist on deep, infertile sands.Crimson clover has some tolerance to transient waterlogging, but is not as well adapted as Persian and Balansa clovers to extended periods of waterlogging.Not tolerant of salinity.

Temperature:

Tolerant to frosts.

Management:

Grazing/cutting:

Crimson clover can be grazed heavily in winter and early spring. Grazing must be reduced from flowering onwards to achieve good seed yields. During this time stock can be transferred to subterranean clover pastures.

In dairy areas, crimson clover is a good silage or hay option. Crimson clover grows rapidly in winter and can be grazed heavily during this time. In spring, grazing pressure should be reduced for silage or hay production.

Seed production:

While the aerial seeding habit of crimson clover makes it easy to header harvest, threshing the seed is difficult. This is because the seed pods are difficult to separate from a tough calyx that encloses them. In Western Australia, some of the most successful harvesting operations have used open front, finger tine machinery with drum speeds of 800 to 900 rpm and a gap of 1 - 3 mm.

Ability to spread:

Limited

Weed potential:

There have not been reported cases of crimson clover growing within native vegetation.

Major pests:

Crimson clover is susceptible to damage by red-legged earth mite particularly at the seedling stage. It is also susceptible to attack by blue-green aphids.

Major diseases:

A number of fungal diseases can affect crimson clover. These include crown and stem rot, which is most prevalent during wet winters in ungrazed swards. Fusarium wilt and fusarium root rot may also affect crimson clover. The incidence of these diseases may be reduced by avoiding sowing crimson clover on poorly-drained soils, and by moderate grazing through winter to reduce humidity in the canopy, which is conducive to fungal growth.

Crimson clover is also susceptible to virus diseases, particularly Bean Yellow Mosaic Virus.Crimson clover is generally tolerant of the clover scorch disease (Kabatiella caulivora), which is common in many areas of southern Australia where clovers are grown.

Herbicide susceptibility:

• Crimson clover is reasonably tolerant to most of the broad-leaf herbicides available.
• Grass weeds can be safely controlled with common grass-selective herbicides.