**Malva parviflora L. (Malvaceae)**

**Cheeseweed, Little Mallow, Small-fruited Mallow**

**Description**. Annual, from a deep taproot, glabrous or sparsely
pubescent with stellate hairs; stems 1-10 dm tall, prostrate to
ascending, simple or branched. Leaves alternate, stipulate, the stipules
linear to narrowly triangular, the blades 2- 10 cm long, 2-9 cm wide,
round to reniform, with 5 or 7 lobes, margins crenate to dentate, bases
cordate to subcordate, apices rounded. Flowers 2-4, in axillary
clusters, peduncles 2-15 mm long, calyx subtended by an involucel of 3
linear bracts that are 1-2 mm long; calyx lobes 5, 3-4 mm long, broadly
ovate, spreading in fruit, apices mucronate; corolla of 5 lobes, 4-6 mm
long, pink to white, glabrous; stamens many, fused into a tube
surrounding the style; ovary superior, fruit circular, the central
portion depressed, separating into rugose to reticulate segments at
maturity, the margins of the segments slightly winged. In California,
flowering from March to September (Dalby 1968, Fernald 1950, Gleason and
Cronquist 1991, Hill 1993, Thompson and Barker 1986).

The related *Malva nicaensis* (bull mallow) is characterized by having
sepals curved over the fruit, darker colored petals (pink to violet)
8-15 mm long, with ciliate claws, and fruit segments that are angled but
unwinged (Dalby 1964; Hill 1993). The closest relative of *Malva
nicaensis* All appears to be *Lavatera cretica* L. rather than other
species of *Malva* (in the strict sense according to Ray 1995, 1998).

**Geographic distribution**. A native of Europe, *Malva parviflora* is
widely naturalized in North America, Australia, New Zealand, southern
Africa, and Hawaii (Arnold and de Wet 1993, Chapman 1991, Gleason and
Cronquist 1991, Hill 1993, Mitich 1990, Wagner et al. 1990, Webb et al.
1988). In addition to the above regions, *Malva nicaensis* has also
become naturalized in Chile (Montenegro et al. 1991).

By the late 19th century *Malva parviflora* had become recognized as a
weed throughout coastal California (Hilgard 1890), although it probably
was established near early Spanish setlements during the late 18th
century (Hendry and Bellue 1925).

*Malva parviflora* is reported from all California Channel Islands, but
*M. nicaensis* is known only from Santa Cruz Island (Junak et al. 1993.
1997). Although *M. parviflora* appears distributed throughout
California, *M. nicaeensis* has been reported only from most coastal
counties and the San Joaquin Valley (Anonymous 1998; Munz 1959).

**Reproductive and vegetative biology**. No literature pertinent to the
reproductive and vegetative biology of *Malva parviflora*, *M.
nicaensis*, and related species was found. Like other weedy Malvaceae,
these species presumably are self-compatible, partly self-pollinating,
and visited by small bees and flies (Faegri and van der Pijl 1979).

**Ecological distribution.** Cheeseweed and related species occur in
waste places, cultivated fields, disturbed sites, rocky slopes, and
grasslands (Fernald 1950, Gleason and Cronquist 1991, Hill 1993, Mitich
1990, Munz 1959, Thompson and Barker 1986).

**Weed status.** *Malva parviflora* is not considered a noxious weed in
agricultural or horticultural practice, at least at a global level (not
listed by Holm et al. 1977), nor is it considered a noxious weed by the
State Dept. of Food and Agriculture (Anonymous 1996). Only *Malva
neglecta* Wallr. (common mallow) is listed for the United States in
Lorenzi and Jeffery (1987).

**Microbial pathogens**. Potato Y potyvirus has been reported in *Malva
parviflora* (Espino De Paz et al. 1997). Although cheeseweed is
susceptible to tomato spotted wilt tospovirus, it is apparently
resistant to the primary vector, a thrip (Bautista et al. 1995). A
fungus (*Colletotrichum gloeosporioides* f. sp. *malvae* ) has been
reported to be especially pathogenic to populations of *Malva
parviflora* (Morin et al. 1996).

**Insect pathogens**. *Malva parviflora* has been reported as a host of
the true bug, *Bemisia argentifolii* (Summers1997), thrips (Yudin et al.
1988), and the tipworm, *Crocidosema plebejana* (Hamilton and Zalucki
1993a, 1993b). *Malva* *nicaeensis* has been reported as a host of the
cerambycid beetle, *Plagionotus scalaris* (Lopez-Colon 1994).

**Herbicide control**. Wells and Appleby (1992) studied physiological
effects of glyphosate on *Malva parviflora*. No other literature on
herbicide control of either *M. parviflora* or *M. nicaensis* was found.
However, Lorenzi and Jeffery (1987) recommended the use of atrazine,
bromacil, 2,4-D, dicamba, and tebuthiuron for control of *M. neglecta*.

**Literature Cited**

Anonymous, 1996. Exotic pest plants of greatest concern in California as
of August 1996. California Exotic Pest Plant Council. 8 pp.

Anonymous. 1998. California county flora database version 2, Santa
Barbara Botanic Garden and USDA National Plants Data Center, Santa
Barbara and New Orleans. URL = plants.usda.gov

Arnold, T. and B. de Wet. 1993. Memoir 62. Plants of southern Africa:
names and distribution. National Botanical Institute, Pretoria. 825 pp.

Bautista, R., R. Mau, R, J. Cho, and D. Custer. 1995. Potential of
tomato spotted wilt tospovirus plant hosts in Hawaii as virus reservoirs
for transmission by *Frankliniella occidentalis* (Thysanoptera:
Thripidae). Phytopathology. 85: 953-958.

Chapman, A. 1991. Australian plant name index. K-P. Australian
Government Publishing Service, Canberra. pp. 1711-2495.

Espino De Paz, A., P. Mendez Perez, and C. Jorda-Gutierrez. 1997. New
hosts of potato Y potyvirus (PVY) identified in the Canary Islands.
Plant Disease. 81: 1096.

Faegri, K. and L. van der Pijl. 1979. The principles of pollination
ecology. Pergamon Press, Oxford.

Fernald, M. 1950. Gray's manual of botany. American Book Company, New
York. 1632 pp.

Gleason, H. and A. Cronquist. 1991. Manual of the vascular plants of
northeastern United States and Adjacent Canada. 2nd edition. New York
Botanic Garden, Bronx. 910 pp.

Hamilton, J. and M. Zalucki. 1993a. Interactions between a specialist
herbivore *Crocidosema plebejana* and its host *plants Malva parviflora*
and Cotton, *Gossypium hirsutum* . Oviposition preference. Entomologia
Experimentalis et Applicata. 66: 207- 212.

Hamilton, J. and M. Zalucki. 1993b. Interactions between a specialist
herbivore *Crocidosema plebejana* and its host *plants Malva parviflora*
and Cotton, *Gossypium hirsutum.*. Larval performance. Entomologia
Experimentalis et Applicata. 66: 199- 205.

Hendry, G. and M. Bellue. 1925. The plant content of adobe bricks.
California Historical Society Quarterly 4: 361-373.

Hilgard, E. 1890. The weeds of California. California Agricultural
Station Report. pp. 238-252.

Hill, S. 1993. *Malva*. p 754. In Hickman, J. (ed.). The Jepson manual:
Vascular plants of California. University of California Press, Berkeley.
1400 pp.

Junak, S., T. Ayers, R. Scott, D. Young, and D. Wilken. 1993. A flora of
Santa Cruz Island. Santa Barbara Botanic Garden and the California
Native Plant Society. 397 pp.

Junak, S., S. Chaney, R. Philbrick, and R. Clark. 1997. A checklist of
vascular plants of Channel Islands National Park. Southwest Parks and
Monuments Association, Tucson, AZ. 43 pp.

Lopez-Colon, J. 1994. New data on the Central Spain populations of
*Plagionotus scalaris* (Cerambycidae). Nouvelle Revue d\'Entomologie.
11: 209-210.

Mitich, L. 1990. Cheeseweed - the common mallows. Weed Technology. 4:
693-695.

Montenegro, C., S. Teillier, P. Arce, and V. Poblete. 1991. Introduction
of plants into the

mediterranean-type climate area of Chile. pp. 103-114. In Groves, R. and
F. Di Castri.

Biogeography of Mediterranean invasions. Cambridge University Press,
Cambridge. 485 pp.

Morin, L., J. Derby, and E. Kokko. 1996. Infection process of
*Colletotrichum gloeosporioides* f. sp. *malvae* on Malvaceae weeds.
Mycological Research. 100: 165- 172.

Munz, P. 1959. A flora of California. University of California Press,
Berkeley. 1681 pp.

Ray, M. 1995. Systematics of *Lavatera* and *Malva* (Malvaceae,
Malveae) - a new perspective. Plant Systematics and Evolution 198:
29-53.

Ray, M. 1998. New combinations in *Malva* (Malvaceae: Malveae). Novon 8:
288-295.

Summers, C. 1997. Phototactic behavior of *Bemisia argentifolii*
(Homoptera: Aleyrodidae) crawlers. Annals of the Entomological Society
of America. 90: 372-379.

Thompson, J. and W. Barker. 1986. Malvaceae. pp. 240-252. In Great
Plains Flora Association. 1986. Flora of the Great Plains. University of
Kansas, Lawrence. 1392 pp.

Wagner, W., D. Herbst, and S. Sohmer. 1990. Manual of the flowering
plants of Hawaii. 1853 pp.

Webb, C., W. Sykes, and P. Garnock-Jones. 1988. Flora of New Zealand.
Volume 4. Naturalized pteridophytes, gymnosperms, dicotyledons.
Department of Scientific and Industrial Research, Christchurch. 1365 pp.

Wells, B. and A. Appleby. 1992. Lactofen increases glyphosate-stimulated
shikimate production in little mallow (*Malva parviflora*). Weed
Science. 40: 171-173.

Yudin, L., B. Tabashnik, J. Cho, and W. Mitchell. 1988. Colonization of
weeds and lettuce by thrips (Thysanoptera: Thripidae). Environmental
Entomology. 17: 522- 526.