Black vine weevil
Encyclopedia
Otiorhynchus sulcatus, commonly known as the black vine weevil, is native to Europe, but common in North America as well. It is a pest of many garden plants.
Grubs grow up to 1 cm in length, have a slightly curved, legless body, creamy-white in colour, with a tan-brown head. They live below the soil surface, and feed on roots and cambium
at the base of the trunk. They cause most damage to herbaceous plants, particularly those growing in containers, where root growth is restricted. Severe infestations can result in complete root destruction and hence plant death.
The soil dwelling grubs can be controlled using predatory nematode
s which can be bought from some garden centres, and by mail order. They are simply mixed with water, and watered onto the soil.
Adult weevils can be controlled by using sticky barriers on the trunks of affected plants, as the weevils return to the soil each day.
Adults can also be manually removed from plants at night when they can be found feeding on leaf edges. Use only a dim torch or candlelight to search by, as they will drop to the ground if startled by bright light.
Adults may also be controlled using the fungus Beauveria bassiana
, which is a biocontrol
.
Overview
The adult weevil is matte black with fused wing covers, and is unable to fly. It feeds at night on the outer edges of leaves, causing the leaves to have a notched margin. Broadleaved evergreen plants such as camellia, rhododendron, euonymus and bergenia are particularly prone to damage, although a wide range of different garden plants is susceptible to attack.Grubs grow up to 1 cm in length, have a slightly curved, legless body, creamy-white in colour, with a tan-brown head. They live below the soil surface, and feed on roots and cambium
Cambium (botany)
A cambium , in botany, is a tissue layer that provide undifferentiated cells for plant growth. It forms parallel rows of cells, which result in secondary tissues....
at the base of the trunk. They cause most damage to herbaceous plants, particularly those growing in containers, where root growth is restricted. Severe infestations can result in complete root destruction and hence plant death.
Host Plants
The host plants include the following, listed by genus:- ArisaemaArisaemaArisaema is a genus of about 150 species in the flowering plant family Araceae, native to eastern and central Africa, Asia and eastern North America. Its species are often called Cobra lilies, particularly the Asiatic species...
- Aster
- AstilbeAstilbeAstilbe is a genus of 18 species of perennial, herbaceous flowering plants, within the family Saxifragaceae. Some species are commonly known as False Goat's Beard, and False Spirea...
- BergeniaBergeniaBergenia is a genus of ten species of flowering plants in the family Saxifragaceae, native to central Asia, from Afghanistan to China and the Himalayan region...
- CamelliaCamelliaCamellia, the camellias, is a genus of flowering plants in the family Theaceae. They are found in eastern and southern Asia, from the Himalaya east to Korea and Indonesia. There are 100–250 described species, with some controversy over the exact number...
- EchinaceaEchinaceaEchinacea is a genus of herbaceous flowering plants in the daisy family, Asteraceae. The nine species it contains are commonly called purple coneflowers. They are endemic to eastern and central North America, where they are found growing in moist to dry prairies and open wooded areas. They have...
- EpimediumEpimediumEpimedium, also known as Rowdy Lamb Herb, Barrenwort, Bishop's Hat, Fairy Wings, Horny Goat Weed, or Yin Yang Huo , is a genus of about 60 or more species of herbaceous flowering plants in the family Berberidaceae...
- EuonymusEuonymusEuonymus , often called spindle or spindle tree, is a genus of flowering plants in the staff vine family, Celastraceae. It comprises about 170–180 species of deciduous and evergreen shrubs and small trees...
- HeucheraHeucheraThe genus Heuchera includes at least 50 species of herbaceous perennial plants in the family Saxifragaceae, all native to North America. Common names include alumroot and coral bells. They have palmately lobed leaves on long petioles, and a thick, woody rootstock...
- HostaHostaHosta is a genus of about 23–45 species of lily-like plants in the family Asparagaceae, subfamily Agavoideae, native to northeast Asia. They have been placed in their own family, Hostaceae ; like many 'lilioid monocots', they were once classified in the Liliaceae...
- KalmiaKalmiaKalmia is a genus of about 8 species of evergreen shrubs from 0.2–5 m tall, in the family Ericaceae. They are native to North America and Cuba. They grow in acidic soils, with different species in wet acid bog habitats and dry, sandy soils Kalmia is a genus of about 8 species of evergreen shrubs...
- LiliumLiliumLilium is a genus of herbaceous flowering plants growing from bulbs. Most species are native to the temperate northern hemisphere, though the range extends into the northern subtropics...
- PhloxPhloxPhlox is a genus of 67 species of perennial and annual plants found mostly in North America in diverse habitats from alpine tundra to open woodland and prairie. Some flower in spring, others in summer and autumn....
- RhododendronRhododendronRhododendron is a genus of over 1 000 species of woody plants in the heath family, most with showy flowers...
- SedumSedumSedum is a large genus of flowering plants in the family Crassulaceae, members of which are commonly known as stonecrops. It contains around 400 species of leaf succulents that are found throughout the Northern Hemisphere, varying from annual and creeping herbs to shrubs. The plants have...
- Syringa
- TaxusTaxusTaxus is a genus of yews, small coniferous trees or shrubs in the yew family Taxaceae. They are relatively slow-growing and can be very long-lived, and reach heights of 1-40 m, with trunk diameters of up to 4 m...
- TsugaTsugaTsuga is a genus of conifers in the family Pinaceae. The common name hemlock is derived from a perceived similarity in the smell of its crushed foliage to that of the unrelated plant poison hemlock....
- WisteriaWisteriaWisteria is a genus of flowering plants in the pea family, Fabaceae, that includes ten species of woody climbing vines native to the eastern United States and to China, Korea, and Japan. Aquarists refer to the species Hygrophila difformis, in the family Acanthaceae, as Water Wisteria...
Organic Controls
Nematode
The nematodes or roundworms are the most diverse phylum of pseudocoelomates, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 28,000 have been described, of which over 16,000 are parasitic. It has been estimated that the total number of nematode...
s which can be bought from some garden centres, and by mail order. They are simply mixed with water, and watered onto the soil.
Adult weevils can be controlled by using sticky barriers on the trunks of affected plants, as the weevils return to the soil each day.
Adults can also be manually removed from plants at night when they can be found feeding on leaf edges. Use only a dim torch or candlelight to search by, as they will drop to the ground if startled by bright light.
Adults may also be controlled using the fungus Beauveria bassiana
Beauveria bassiana
Beauveria bassiana is a fungus that grows naturally in soils throughout the world and acts as a parasite on various arthropod species, causing white muscardine disease; it thus belongs to the entomopathogenic fungi. It is being used as a biological insecticide to control a number of pests such as...
, which is a biocontrol
BioControl
BioControl is a peer-reviewed scientific journal published by Springer Science+Business Media covering all aspects of basic and applied research in biological control of invertebrate, vertebrate, and weed pests, and plant diseases. The journal was established in 1956 as Entomophaga and published by...
.