Convolvulus arvensis L.Convolvulaceae (Morning-Glory Family)Eurasia
BindweedWild Morning-GloryOrchard Morning-Glory
|
July Photo
Plant Characteristics:
Perennial, with a long taproot, herbage glabrous to pubescent; lf. blades
oblong-sagittate to ovate to rounded at apex, mostly 1.5-3.5 cm. long; petioles
slender, shorter than the blades; peduncles commonly 1 fld., sometimes 2-3 fld.;
peduncle 1-2 in. long with a pair of subulate bracts 2-4 mm. long near the
middle; corolla white, purplish outside, open-funnelform and neither lobed nor
angled. Not
mentioned in Munz, but a characteristic I have noticed are the purple stripes on
the back of the corolla. (my
comment).
Habitat:
Deep rooted and troublesome weed in orchards and fields; waste places
below 5000 ft.
Name:
Latin, convolvere, to entwine. (Munz, Calif.
Flora 375). New Latin, arvensis, of or belonging to the field. (Jaeger 26).
General:
Occasional in the study area. Photographed
on the North Star Flats and along Back Bay Dr. near the old Salt Works dike.
(my comments).
The root is a purgative, hydragogue, cathartic, and diuretic.
(Coon 230).
The plant has an adverse effect on agriculture and is widely
distributed throughout the state. Control
must be figured into the cost of production.
Up to 100% crop loss from this weed could be anticipated in the cotton
crop without control. (FREMONTIA,
A Journal of the California Native Plant Society.
July 1985. Author and title
of article not recorded).
The root system of this plant is characterized by the production of
annual laterals in great numbers. These
laterals develop adventitiously throughout the length of the taproot and its
branches, and permeate the soil in all directions.
Most of them die at the end of the season and are replaced by new ones
each year; but any which have become favorably situated may make more than
average growth and become so well developed that they persist as permanent
branches. It is by means of these
persistent laterals that spreading in a horizontal direction is accomplished.
Shoot buds arise on these horizontal laterals and develop into rhizomes
which, reaching the surface, establish new crowns.
The unusual ability of the morning-glory plant to reproduce vegetatively
is related to the form of its underground structures.
The relatively large storage capacity of the root necessitates the
existence of many living cells in close relation with a large supply of food,
and an efficient system for absorbing mineral nutrients. These conditions favor bud formation, which is the most
characteristic habit of the plant. Favorable
growing conditions stimulate intense activity, and these buds may be produced by
dozens or even hundreds, especially during warm weather and after a cultivation
that has destroyed the top growth. The
ability to produce buds, together with the food reserve of the root, favors
vegetative reproduction and makes the plant persistent.
The dense foliage and twining growth enable the plant to choke out
competitors and present difficulties to thorough spraying.
Although the species of Convolvulus
contain a toxic milky juice in the roots, no well-authenticated cases of poisoning have been reported.
There is evidence, however, that "hair-balls" in sheep are
largely composed of fibers of these plants. (Robbins et al. 340,343).
C. arvensis has been found to
accumulate free nitrates in quantities capable of causing death or distress in
cattle. (Fuller 385).
The seeds of C.
arvensis are poisonous.
Eating a quantity of the seeds causes nausea, digestive upset,
hallucinations, blurred vision, mental confusion, lack of coordination, stupor
and coma. The nervous system may
show great contrast; even in the same individual and at the same instance, they
can change rapidly. (James 49).
A fairly large genus of wide distribution.
(Munz, Flora So. Calif. 375).
Text Ref:
Collins 181; Hickman, Ed. 521; Munz,
Calif. Flora 375; Robbins et al. 342; Roberts 20.
Photo Ref:
June 7 83 # 14,15; July 1 83 # 5.
Identity: by R. De Ruff,
confirmed by F. Roberts.
First Found: June 1983.
Computer Ref: Plant Data 231.
Have plant specimen.
Last edit 3/4/05.
July Photo June Photo