PNW 447 • Revised March 2003 Wild Carrot Daucus carota L.

J. Colquhoun, J.P. Fitzsimmons, and L.C. Burrill

ild carrot (Daucus carota), also known as WQueen Anne’s lace, was introduced from Europe and is the genetic source of edible carrots. It is a problem in perennial cropping systems such as grass seed production, pasture and hay fields, and Christmas tree production. It is an especially serious threat where cultivated carrot seed is Figure 2.—Note the curved bracts at the produced because it hybridizes base of the flower, which are unique to with the crop and ruins crop wild carrot. seed. Wild carrot is the pre- dominant weed in many undisturbed habitats. Wild carrot is widely distrib- uted in North America, Europe, and Asia. It is abundant west of the Cascades in Oregon and Figure 1.—Mature wild carrot plant. Washington and is well estab- lished locally on the east side of digestive tract. Sheep seem to the mountains. Wild carrot is a graze wild carrot without any Class B noxious weed in Wash- harmful effect. Figure 3.—From left, seeds of wild chervil (joined and single), hedgeparsley, bur ington, and the transport or sale chervil, poison hemlock, and wild carrot. of wild carrot seed in packets, Identification flower seed blends, or wild- flower mixes is prohibited. Wild carrot forms a rosette of Counties in the Columbia Basin leaves the first year, then flow- where carrot seed is grown ers, produces seed, and dies the require control of wild carrot. second year. Wild carrot also is There is no record of wild known as Queen Anne’s lace carrot toxicity in this country, because the finely cut, lacy but there are reports from leaves often were used in fash- Europe that wild carrot can be ionable headdresses and bou- mildly toxic to horses, cattle, quets during the 17th, 18th, and Figure 4.—Wild carrot seedling. and pigs. Animals usually 19th centuries. avoid grazing it, but a high con- Wild carrot forms a deep, centration of wild carrot in hay whitish taproot that has a dis- Revised by Jed Colquhoun, Extension is a potential problem because tinctive carrot odor. Mature weed specialist. Originally prepared by Jim P. Fitzsimmons, former livestock eat hay less selectively plants reach 2 to 4 feet high and graduate student in crop and soil than green forage. Ingestion of have erect stems and few science, and Larry C. Burrill, Extension large quantities can irritate the branches (Figure 1). Stiff hairs weed specialist emeritus; Oregon State University.

A Pacific Northwest Extension Publication • Oregon State University • University of Idaho • Washington State University cover the entire plant. Leaves crop is reduced after the first Chemical divide several times, forming cutting. many long, narrow segments. Wild carrot emergence is con- Chemical control is more Leaves on the lower part of the tinuous and evenly distributed effective when herbicides are plant have stalks. Those on the throughout the wet season in applied to plants in the seedling upper part of the plant are the Pacific Northwest. In the stage (Figure 4). As plants attached directly to the stem. winters of 2000–2001 and mature, herbicides are ineffec- White flowers are clustered at 2001–2002, wild carrot emer- tive, or more chemical is the end of the stem in flat, gence was monitored at 12 sites required to kill the plants. umbrellalike structures in the Willamette Valley of Yearly applications are neces- (umbels) 2 to 4 inches in diam- Oregon. Emergence was vari- sary to control the young eter. One to several flowers in able within a given period, seedlings that arise from the the center of the umbel often but it can occur any time from soil seed bank. are purple-tinged. Umbels are October through March. Herbicide registrations surrounded at the base by long, change frequently; therefore, forked modified leaf structures Control this publication does not con- or bracts (Figure 2). Other tain specific herbicide use instructions. Registered uses are plants that might be confused Cultural with wild carrot lack these con- summarized each year in the spicuous bracts. As with all weeds, prevention Pacific Northwest Weed Manage- Flowering occurs from July to of wild carrot seed dissemina- ment Handbook. September. When the seeds tion in cultivated fields will In addition, detailed instruc- ripen, the umbels contract into help avoid costly and trouble- tions for herbicide use are the shape of a hollow cup or some weed infestations. provided on herbicide nest. Seeds are 0.12 to 0.17 inch Therefore, control of wild carrot container labels and in other long with one distinctly flat side in noncropland roadside literature provided by herbicide and one rounded side that is ditches and field edges is criti- manufacturers. ridged with bristles (Figure 3). cal to the maintenance of a Seeds may remain on the plant weed-free crop. Grazing is rela- after it dies, falling gradually tively ineffective because the Use pesticides safely! throughout the winter as central stalk is grazed first, • Wear protective clothing weathering occurs. allowing woody, less palatable secondary stalks to develop and and safety devices as produce viable seed. recommended on the label. Ecology Bathe or shower after each Mechanical use. Wild carrot often is found in • Read the pesticide label— gravelly or sandy soils and in Wild carrot often is found in even if you’ve used the wet areas. It is most prolific in waste areas, old pastures, and pesticide before. Follow areas with 32 to 40 inches of meadows. Plowing these areas closely the instructions on annual precipitation or irriga- and planting to a cultivated the label (and any other tion and at least 120 consecutive crop for 2 years decreases the directions you have). frost-free days. Vigor and seed infestation. Frequent cultivation • Be cautious when you production decrease with in these crops promotes seed apply pesticides. Know increased shading; a severely germination and destroys the your legal responsibility as shaded wild carrot will act as a seedlings before plants can a pesticide applicator. You short-lived perennial. Often, the flower and produce seed. This may be liable for injury or second cutting of a hay field is process helps deplete the sup- damage resulting from mostly wild carrot because ply of seeds in the soil. Another pesticide use. competition for light from the approach is to mow after stems elongate but before flowering.

© 2003 Oregon State University. This publication may be photocopied or reprinted in its entirety for noncommercial purposes. Published and distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914, by the Oregon State University Extension Service, Washington State University Cooperative Extension, the University of Idaho Cooperative Extension System, and the U.S. Depart- ment of Agriculture cooperating. The three participating Extension Services offer educational programs, activities, and materials—without regard to race, color, religion, sex, sexual orientation, national origin, age, marital status, disability, and disabled veteran or Vietnam-era veteran status—as required by Title VI of the Civil Rights Act of 1964, Title IX of the Education Amendments of 1972, and Section 504 of the Rehabilitation Act of 1973. The Oregon State University Extension Service, Washington State University Cooperative Extension, and the University of Idaho Cooperative Extension System are Equal Opportunity Employers. Published March 1993; revised March 2003. $1.00