Seeds that tumble weeds produce salsoa iberica

Russian Thistle

  • An annual, each plant dies every year and new plants grow from seed.
  • Germinates between late April and August; flowers late June through August; goes to seed August to November; dies after the first fall frost and breaks at the base of the stem now through the following spring to spread seed as a tumbleweed.
  • Seeds need loose soil and are not viable for more than a year or so (meaning, you can beat this weed!).

Prevention & Control

Prevent

  • Detect and eradicate new plants early; look for last year’s tumbleweeds as a clue.
  • Do not drive vehicles and machinery through areas with old tumbleweeds.
  • Screen irrigation water before it enters a field or your irrigation pipes.

Hand Pull

  • Hand-pulling or hoeing is the best and easiest method for small or sporadic patches as the roots are shallow and the plant grows from seed (not roots).
  • Seeds germinate throughout the spring and summer so check your property often.

Mowing, Grazing Cultivation and Biocontrols

  • Mowing or otherwise destroying young plants prevents seed production.
  • Planting competitive desirable species, such as tall grass or shrubs can effectively shade out sunlight and suppress weed seedlings.
  • Grazing works well for young plants.
  • Several potential biocontrols are under investigation but none exist now.

See the whole “Toolbox of Weed Control Methods” for more details.

Interesting Tidbits

  • Russian thistle is the primary host for the beet leafhopper (Circulifera tenellus) that carries the “curly-top virus” of sugar beets, tomatoes, squashes, melons and cucumbers.
  • Russian thistle tumbleweeds present a serious fire hazard.

Stay in touch

We’ll send you emails once a month with all the latest news from conservation in the Methow Valley.

Seeds that tumble weeds produce salsoa iberica

Our systems have detected unusual traffic activity from your network. Please complete this reCAPTCHA to demonstrate that it’s you making the requests and not a robot. If you are having trouble seeing or completing this challenge, this page may help. If you continue to experience issues, you can contact JSTOR support.

Block Reference: #451d27fd-e053-11ec-8a2d-496864615777
VID: #
IP: 195.2.73.67
Date and time: Mon, 30 May 2022 20:01:18 GMT

©2000- ITHAKA. All Rights Reserved. JSTOR®, the JSTOR logo, JPASS®, and ITHAKA® are registered trademarks of ITHAKA.

See also  Weed with no seeds

Salsola tragus L.

Russian-thistle is an exotic, annual, erect, xerohalophytic forb. It is highly branched and rounded in form, growing from 1 to 3 feet (0.3-1 m) in height and from 1 to 5 feet (0.3-1.5 m) in diameter. Classic “tumbling tumbleweeds” recognized as an icon of the semiarid American West. The rolling weeds are the mature plants that have autodetached from the roots to begin rolling around the land, spreading seed. The new seedlings and young plants are bright green and grassy. As they develop a more busy form, the stems are red or purple striped and can grow up top 4 ft. (1.2m) tall.

Stems are rigid, typically curved upward, purple-striated or green. Foliage is bluish green and glabrous, but sometimes covered with short, stiff hairs. Bracts are usually awl-shaped, reflexed, and not overlapping at maturity; the margins are membranous and minutely barbed.

Leaves

Leaves are alternate, at first dark green and soft and narrow (less than 1/8 in. [0.3 cm] wide). Upper leaves are sharply pointed and 1.25 to 2 in. (3.1 to 5 cm) long.

Flowers

From mid-summer to fall small greenish to pink flowers grow from the leaf axil, e3ach protected by a triplet of spine-tipped leaves.

Fruit

Seeds: After drying the main stems of the Russian thistle can break off at the ground level under windy conditions, which allows the plants to disperse the seeds as they tumble with the wind. The skeletons will usually persist for at least one year and are typically found along fences and other structures. Russian thistle reproduces by seed, and germination can occur when night temperatures are below freezing and daytime temperatures reach 2º C, but optimal temperature for germination is generally 44º-95º F. Seeds require very little moisture (about 7.5mm of rainfall) to germinate, and after the moisture falls germination will occur within a few hours. To become established seedlings require loose soil. Seedlings that germinate on firm soil seldom survive because the young root is unable to penetrate the soil. Under field conditions, most seeds survive about 1 year, and a few seeds may survive up to 3 years. Plants about 0.5 m tall can produce about 1500-2000 seeds, and larger plants can produce up to 100,000.

See also  Best yield weed seeds

Images

Life History

Russian thistle grows best on loose, sandy soils, but will grow in any disturbed sites, waste places, roadsides, fields, cultivated fields, and disturbed natural and semi-natural plant communities. All species in the genus Salsola are native to Europe. The taxonomy of Salsola species in the western United States is complex and not fully understood.

Origin and Distribution

Native to Eurasia, Russian-thistle is distributed throughout most arid and semiarid regions of the world. In North America Russian thistle occurs from British Columbia east to Labrador and south through the conterminous United States to northern Mexico. It is most common in central and western regions of Canada and the United States, and along the Atlantic and Gulf coasts. Limited southern and eastern inland populations occur along waste areas and railroad tracks. Russian-thistle is adventitious in Hawaii.

Synonyms

Salsola australis R. Br.
Salsola iberica (Sennen & Pau) Botsch. ex Czerep.
Salsola kali L. subsp. ruthenica (Iljin) Soó
Salsola kali L. subsp. tenuifolia Moq.
Salsola kali L. subsp. tragus (L.) Celak.
Salsola pestifer A. Nelson
Salsola ruthenica Iljin

h2. Management Recommendations

Mechanical Controls

Many mechanical strategies are effective in controlling these thistles. Mowing is effective on very young plants. However, older plants will recover by axial branching below the cutting level. Plants should never be mowed after seed set has occurred, as this will facilitate seed dispersal to new areas.

Tillage will control both seedling and larger plants. However, tillage increases disturbance, which favors additional germination of seeds. Seed viability appears to be 1-3 years for Russian thistle and is unknown for barbwire or spineless Russian thistle. Therefore, an intensive tillage program that completely prevents seed production for 2-3 years may eliminate these thistles. However, recurrent seed depositions from tumbleweeds blowing in from adjacent areas is highly probable.

Hand pulling of large plants is extremely difficult and may be injurious due to the spiny nature of Russian and barbwire thistle. Always wear gloves if attempting to hand pull these species.

Herbicidal Controls

These thistles primarily occur in dryland agricultural production systems, roadsides, rangelands, and waste areas. This presents the need for several different herbicide strategies. Generally, seedling Russian thistle is not difficult to control with the proper herbicides. However, as plants get older, moisture stress is often likely and herbicide efficacy is greatly reduced.

See also  Seed and weed pre emergent

For roadsides, preemergent herbicides applied in the fall can provide season long control. Table 1 provides effective herbicides for roadside Russian thistle control. Post-emergent applications should be made in the seedling stage for effective control. Postemergent applications generally do not provide long term control due to repeated flushes of seed germination following herbicide application. Consult the label for application rates and restrictions.

Russian thistle has documented resistance to chlorsulfuron in Idaho, Oregon, and Washington. In California, a biotype with resistance to both chlorsulfuron and sulfometuron has been found. Avoid developing resistance by using a combination of management strategies and rotating between herbicide modes of action.

Biological Controls

There are two insects that have been approved and released for control of Russian thistle: a leaf mining moth Coleophora klimeschiella and a stem boring moth Coloephora parthenica. Both are available for release in California. Beyond its known establishment in central California, there is little information on the effectiveness of Coleophora klimeschiella. Coloephora parthenica has not been effective in reducing Russian thistle populations. There are a number of possible factors for this, including predation by rodents, spiders, and parasitoids; poor host plant synchronization due to herbivore independent mortality; and a general lack of effectiveness in reducing seed production. Recent taxonomic reconsideration of Salsola tragus and its possible biotypes or subspecies may bring further clarity to the effectiveness of this biocontrol agent.

Bibliography

Kaufman, S. R. and W. Kaufman. Invasive Plants: Guide to Identification and the Impacts and Control of Common North American Species. Stackpole Books, Mechanicsburg, PA. 2007. 264-266 pp.

DiTomaso, J. M. and E. A. Healy. 2007. Weeds of California and Other Western States. Volume 1: Aizoaceae to Fabaceae. University of California Department of Agriculture and Natural Resources: 622-632

Young, F. L. and Whitesides, R. E. 1987. Efficacy of postharvest herbicides on Russian thistle (Salsola iberica) control and seed germination. Weed Science 35:554-559

Young, F. L. 1988. Effect of Russian thistle Salsola iberica interference on spring wheat Triticum aestivum. Weed Science 36:594-598.