HPIPM:Velvetleaf
Taxonomy
| Domain | Eukarya |
|---|---|
| Kingdom | Plantae |
| Phylum | Magnoliophyta |
| Class | Magnoliopsida |
| Superorder | Rosanae |
| Order | Malvales |
| Family | Malvaceae |
| Genus | Abutilon |
Scientific Name
Common Name
Velvetleaf (Abutilon theophrasti)
Compiled by Jeff Edwards, University of Wyoming, Goshen County Extension.
and Marjolein Schat, Montana State University from the following sources:
http://na.fs.fed.us/FHP/INVASIVE_PLANTS/weeds/velvetleaf.pdf
http://plants.usda.gov/java/profile?symbol=ABTH
Identification and Life Cycle
Velvetleaf (Abutilon theophrasti) is an introduced annual in the mallow family (Malvaceae). Velvetleaf is also knows as Indian mallow, China-jute, pie-maker, abutilon-hemp, buttonweed, and velvet weed. The plant is erect and shrub-like with alternate heart-shaped leaves. Stems are have soft hairs and can grow up to 7 seven feet tall. Leaves are 2 to 6 inches long and wide, with dense hairs on both surfaces. Leaf margins are toothed and leaves emit an unpleasant odor when crushed. Flowers are solitary, yellow, are 1/2 to 1 inch wide, and have 5 petals. Seeds are produced in a circular capsule fruit approximately 1 inch in diameter with a ring of spines around the upper edge. Each capsule has a 10 – 15 seedpods that produce 5 - 15 seeds each. Velvetleaf has a fibrous taproot.
Habitats
Velvetleaf grows along roadsides, ditches, hillside slopes, riverbanks, disturbed areas, and cultivated fields.
Impacts
Velvetleaf causes the most concern in row crops, mainly soy bean, corn and cotton where it outcompetes the strongest cultivated plants for water and soil nutrients. Yield reductions of 20-34% have been attributed to velvetleaf in corn. Velvetleaf is also known to have allelopathic affects on the seed germination and seedling root elongation of other plants. Laboratory studies show that velvetleaf extracts depressed the germination and growth of alfalfa, maize, radish, soybean, and turnip seedlings.
Biology and Ecology
Velvet leaf reproduced from seed and seedlings emerge in spring and early summer. Seeds germinate from soil depths of 2 inches. Seeds that germinate on the soil surface die. Once the seedling emerges, a tap root develops, allowing the seedling to become quickly established. The seedlings exhibit rapid growth upon emergence, often exceeding the crop heights by mid-growing season. Velvetleaf blooms from late summer through early fall. Flowers are short lived. Each plant can produce 700 – 17,000 seeds. Seeds exhibit dormancy and can survive in the soil for over 50 years. Seeds can also remain viable after passing through animal digestive tracks.
Management Approaches
Prevention of formation of a seed bank is essential for controlling velvetleaf.
Biological Control
Ten fungal species and six insects have been reported to affect velvetleaf plants. There are several organisms that are being studied for possible use as biocontrol agents, though none are currently available for release. The scentless plant bug (Niesthrea louisianica) caused a 98% seed reduction. In addition Fusarium lateritium and Colletotrichum coccodes are mycoherbicides being studied for velvetleaf suppression. Rhizobacteria have also been studied for control of seedlings. Several root nematdes (Heterodera marioni, Medoidogyne ssp.) parasitized velvetleaf under greenhouse. Velvetleaf is a wild host to tobacco budworm (Heliothis virescens) and bollworm (H. zea), which feed on the terminal shoots, young leaves and immature fruits. However, these insects are serious crop pests and cannot be encouraged for control of velvetleaf.
Mechanical and Cultural Control
Close mowing is effective if mowed prior to seed production. Velvetleaf becomes less of a problem in no-till systems because the seed germinates on the soil surface and the seedlings do not survive. Hoeing is successful if the velvetleaf plants are less than 1/4" in height. Because velvetleaf can emerge from a 2" depth in the soil profile, it is difficult to remove with a rotary hoe once it is established.
Chemical Control
Consult herbicide labels for additional rate, application, and safety information. Additional herbicide information can be found at http://www.greenbook.net.
Due to constantly changing labels, laws and regulations, the sponsors of this web site assume no liability for the suggested use of any chemicals noted in the management section. Contact your local pest management personnel for current information on labeled pesticides that can be used for the intended plant disease, insect pest or weed.
References
For more images please visit IPM Bugwood. http://www.ipmimages.org/search/action.cfm?q=velvetleaf&Start=1&results=59