Duration and Habit: Annual Herb/Forb
From Dixon (2011).
Stems: The stems are slender and widely spread. They are branched and have appressed-bristly hairs. They can grow from 1 to 3 feet tall.
Leaves: The leaves are alternate and 2 to 3 times pinnately divided. The leaflets are shaped ovately to linear-lanceolate and are 0.25 to 2.5 inches long and 0.75 inches wide. They are short and hairy and have toothed margins or are regularly divided. The tips of the leaflets are pointed.
Inflorescence: The flowers are formed into a compound umbel and are loose and open. They are ½ to 2 inches wide and are on slender stalks that are 1 to 5 inches long. They are terminal and lateral and the primary and secondary umbels have 3 to 9 rays that are ½ to 1 inch long.
Flowers: The flowers are tiny and white in color. There are 5 petals and the outer petals usually have 2 lobes.
Fruits: The fruits are densely covered with microscopic hooked bristles and are egg- shaped. They are less than 1/5 inches long and are ribbed. They are greenish or pinkish in color.
Flowering Period: These plants flower in June, July and August.
Ecological Threat: Minimal: Apparently does not reach densities high enough to impact local/native vegetation or ecosystem (Brusati and DiTomaso 2005). NOTE: native pollinators do visit, and it is a food source for the caterpillars of the Black Swallowtail butterfly (Hilty 2012).
Biology & Spread: Spreads by seed. Seeds have hooks, allowing them to be dispersed by animals (and people’s socks).
“Like other members of the Carrot family, the small white flowers attract various insects, including small bees, flies, wasps, and beetles. The caterpillars of the butterfly Papilio polyxenes asterias (Black Swallowtail) feed on the foliage” (Hilty 2012).
U.S. Habitat: “This plant usually grows around waste areas, edges of woods, and low shady places” (Dixon 2011). “The preference is full sun, mesic to dry conditions, and a rather heavy soil containing gravel or clay. Because this plant often grows in soil containing limestone gravel, it appears to tolerate alkaline conditions” (Hilty 2012).
U.S. Nativity: Non-native
Native Origin: Central and southern Europe (although the Natural Resource Conservation Service of the USDA lists it as native to only British Columbia, Canada [http://plants.usda.gov/core/profile?symbol=TOAR]
U.S. Present: AL, AR, CA, GA, IA, ID, IL, IN, KS, KY, LA, MD, MO, MS, NC, NE, NJ, NY, OH, OR, PA, SC, TN, TX, UT, VA, WA, WV
Distribution: For distribution by counties in US (incomplete), see EDDMapsS distribution map (scroll to bottom): http://www.invasiveplantatlas.org/subject.html?sub=6532#maps
List All Observations of Torilis arvensis reported by Citizen Scientists
From Ditomaso et al. (2013).
Physical: Hand pulling is effective on small incipient populations. Pulling is most effective before flowering in late spring when plants are elongated and soil is still moist.
Mowing or disking at flowering stage can provide good control. Resprouts may occur after mowing and a secondary treatment may be required.
Chemical: Refer to Ditomaso et al. (2013) for information on rates, timing, and other comments. Listed herbicides: 2,4-D, Triclopyr, Glyphosate, Chlorsulfuron, Imazapic.
Biological: There are no biological control programs for the management of Torilis arvensis.
Cultural: Grazing can provide some control, if grazed at a high stocking density before flowering. There is no information on the effectiveness of control with prescribed burning.
DiTomaso, J.M., G.B. Kyser et al. 2013. Weed Control in Natural Areas in the Western United States. Weed Research and Information Center, University of California. 544 pp.
Brusati, E. and J.M. DiTomaso. 2005. Plant Assessment Form for Torilis arvensis. California Invasive Plant Inventory, California Invasive Plant Council. http://www.cal-ipc.org/paf/site/paf/440. [Accessed Dec 6 2014]
Constance, Lincoln and Margriet Wetherwax. 2013. Torilis, in Jepson Flora Project (eds.) Jepson eFlora , http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=46743 [Accessed on Dec 5 2014]
Dixon, Kiersten. July 2011. Hedge Parsley. Ninnescah Biology Field Station, Wichita State University. http://ninnescahlife.wichita.edu/node/323, [Accessed Dec 5 2014]
DiTomaso, J.M., G.B. Kyser et al. 2013. Hedgeparsley. In: Weed Control in Natural Areas in the Western United States. Weed Research and Information Center, University of California. 544 pp. http://wric.ucdavis.edu/information/natural%20areas/wr_T/Torilis.pdf. [Accessed Dec 6 2014]
Hilty, John. 2012. Common Hedge Parsley. In: Illinois Wildflowers, http://www.illinoiswildflowers.info/weeds/plants/hdg_parsley.htm. [Accessed Dec 6 2014]
Google Search: Torilis arvensis
Google Images: Torilis arvensis
NatureServe Explorer: Torilis arvensis
USDA Plants: Torilis arvensis
Invasive Plant Atlas of the United States: Torilis arvensis
Bugwood Network Images: Torilis arvensis