FIELD BINDWEED (Convolvulus arvensis) скачать в хорошем качестве

FIELD BINDWEED (Convolvulus arvensis)

How to Identify Field Bindweed (Convolvulus arvensis) This is field bindweed, a member of the morning glory family which is a notoriously noxious weed that was introduced into the Americas from Europe. It is a perennial that blooms from late spring to fall. The plant appears as a group of long, thin climbing vines which wrap themselves around nearby plants and objects. This will often form a dense mat that will smother and choke out other plants. The stems are totally smooth and light green in color. The leaves are arrow shaped with rounded tips. They are smooth, hairless, and dark green in color. The flowers appear from the leaf axils, and are rather distinct in their appearance, having 5 fused petals that form a trumpet shape. They are about an inch in diameter, and are white or pink. One unique component of their identification are the two small bracts which appear about an inch below the flower itself. After being pollinated, the flowers will produce small brown seed pods that each contain two seeds. These seeds are very hardy and can survive in the soil for several decades before germination. The plant has a huge, extensive root system that consists of a long taproot that can penetrate over 10 feet deep into the soil, from which branches multiple long lateral roots. If broken off, any of these root segments can grow into a new plant. In addition to this, the plant will produce lateral rhizomes, which spread very far and have the ability to penetrate various root barriers such as fabric and plastic. Altogether this helps the plants to rapidly take over large patches of soil, and makes it extremely difficult to eradicate. Young stems will produce a milky sap when broken. This plant is highly adaptable, and can tolerate a variety of sun and moisture levels, and prefers disturbed soil. It is common in gardens, fields, croplands, pastures, roadsides, waste sites, and basically everywhere else. Its extensive root system allows it to survive extended periods of drought. Field bindweed can be easily distinguished from other bindweed and morning glory species by its small flower bracts which appear below the flower on the stem. Field bindweed is an extremely invasive weed that regularly causes great damage to cultivated crops and gardens. Dense infestations of the plant can cause loss of crop yield up to 50 percent, and it has been estimated that field bindweed causes hundreds of millions of dollars in crop damages every year. Sources: Weeds of the West, 5th Edition (1991) by Tom D. Whitson, published by the Western Society of Weed Science University of California Agriculture and Natural Resources IPM – Weed Gallery http://ipm.ucanr.edu/ United States Department of Agriculture – Plant Database https://plants.usda.gov