Botanical description: The following descriptions cover characteristics that may be relevant to fire ecology and are not meant for identification. Keys for identification are available (e.g., for bigleaf periwinkle: [29,42,51,78,113]; for common periwinkle: [29,42,78,97,113]).
Periwinkles are vines [42,113] with scrambling or trailing stolons up to 3 feet (1 m) long and vertical stems 1 foot (30 cm) high [72]. The succulent stems become somewhat woody at the caudex [72]. Bigleaf periwinkle leaves are semievergreen [78], have a waxy cuticle [10], and are heart-shaped to triangular. They are 1.5 to 2.5 inches (4 to 6 cm) long [72]. Common periwinkle leaves are evergreen [113], narrow, elliptic, and 0.8 to 1.8 inches (2 to 4.5 cm) long [72].Periwinkle flowers are violet to blue-lavender, with 5 petals radiating pinwheel-like at right angles from floral a tube. Flowers are infrequently white. The flowers of bigleaf periwinkle are larger than those of common periwinkle [72].
Periwinkle fruits are slender, cylindrical follicles up to 2 inches (5 cm) long [72]. Follicles dry, split, and release 3 to 5 seeds (review by [72]). Periwinkle seeds are naked and without a coma [29].
Periwinkles are "fairly deep-rooted" (review by [79]). Common periwinkle plants in western Montana exhibited fibrous roots ranging from 1 to 3 inches (3-8 cm) long [96]. Further descriptions of roots were unavailable as of 2009.
Common (left) and bigleaf (right) periwinkle flowers.
Bigleaf periwinkle is native to Mediterranean Europe [1,4], Asia Minor [1], and northern Africa (review by [10]). Common periwinkle is native across all of continental Europe as far north as the Baltic States [86]. Both bigleaf [51,55,92,107] and common [29,42,50,55,97,100,103,117] periwinkle are frequently planted in North America and escape from cultivation. Periwinkles may also spread with the dumping of yard waste ([17,37], review by [10]). A review of 19th-century floras documented periwinkles in the United States by the late 1700s [112].
In the United States, bigleaf periwinkle has a U-shaped distribution from New York and Massachusetts in the east, south to Georgia, west to California, and north to Washington. Exceptions to this distributional pattern include Connecticut, Rhode Island, New Jersey, West Virginia, Florida, Oklahoma, and Nevada. Bigleaf periwinkle does not occur in the majority of the states in the Northern Great Plains or Northern and Central Rockies. Common periwinkle occurs in every state in the eastern United States from Minnesota south to Louisiana. It is discontinuously distributed in the western United States, occurring in Nebraska, Kansas, Texas, Arizona, Utah, Oregon, Washington, and Montana. The Plants Database provides a map of bigleaf and common periwinkle distributions in North America.
Fuels: As of this writing (2009), there was no information available regarding the flammability of periwinkles. Some evidence suggests that periwinkles may alter local fuel characteristics by changing community structure, litter dynamics, fuel arrangement, and understory temperatures. In Michigan, understory structure in a mixed-hardwood dune successional forest was changed when mats of common periwinkle replaced canopy tree seedlings and herbaceous understory plants [17]. Common periwinkle also greatly reduced the overall accumulation of leaf litter in this area (Bultman personal observation cited in [17]). In mature oak-hickory forest in southwestern Illinois, common periwinkle in the understory led to an increase in the amount of vegetated surface area [88]. Near Sydney, Australia, areas dominated by bigleaf periwinkle had significantly cooler temperatures than sites with little bigleaf periwinkle cover (P<0.01) [31]. The impact of these altered fuel characteristics likely varies based on departure from historical conditions and the dynamics of local FIRE REGIMES.
FIRE REGIMES: It is not known what type of fire regime periwinkles are best adapted to. In North America, periwinkles are found in plant communities that historically experienced long (e.g., northern hardwood, southern floodplain forests) and short (e.g., Appalachian oak-hickory-pine forests) fire-return intervals (see the Fire Regime Table). In many areas where periwinkles occur, historical FIRE REGIMES have been dramatically altered due to fire exclusion and massive disturbances associated with human settlement.
It is unclear how the presence of periwinkles may affect FIRE REGIMES in invaded communities. In ecosystems where periwinkles replace plants with similar fuel characteristics, they may alter fire intensity or slightly modify an existing fire regime. If periwinkle spread introduces novel fuel properties to the invaded ecosystem, fire behavior, and potentially fire regime, may be altered (see these citations: [14,26]). This topic warrants additional study.
Find further fire regime information for the plant communities in which these species may occur by entering the species' names in the FEIS home page under "Find FIRE REGIMES".
General site types: Bigleaf periwinkle occurs in riparian areas ([6,21,29,33,34,49,71,112], reviews by [81,111]), forests ([29], reviews by [72,111]), grasslands, and coastal dunes (review by [111]). Bigleaf periwinkle is also associated with sites linked to human activities, including old homesites ([74,78,94], review by [72]), gardens [55], roadsides [55,92], "waste" areas ([55,78], review by [72]), and other highly disturbed areas [55].
Common periwinkle occurs in forests or "wooded" areas [29,37,45,57,60,78], including both open ([42,100,115], review by [72]) and closed ([53], reviews by [72,81]) forest. Common periwinkle also occurs along forest edges ([37], review by [25]), within second-growth forest [32], and in fields or meadows [77,78,90]. Common periwinkle is found along roadsides [3,18,42,47,48,78,94,97,100,115] or trail edges [47], at homesites ([12,35,50,74,84,85,94,103], review by [72]), in gardens [55] or yards [94], cemeteries [57,97], "waste" places [3,55,78,115], and in other disturbed sites [8,55,101,117]. At an "ancient" archeological site in the oak-beech forest region of France, common periwinkle was most abundant in disturbed areas including abandoned homesites, enclosures, and agricultural terraces, but was also found to a lesser extent in areas that showed no archeological evidence of human disturbance [35].
Elevation: Periwinkles occur at a range of elevations from sea level to 7,500 feet (2,300 m).
Elevation for sites with periwinkles in their nonnative ranges Species Location Elevation (feet) Bigleaf periwinkle California 7 to 650 [49] North Carolina 5 [92] Utah 5,000 [113] Common periwinkle Florida 0 [24] Utah 7,500 [113] West Virginia 1,200 to 2,500 [9,18]Climate: In their nonnative ranges, periwinkles do best in mild climates [4,99]. Few authors report climate data for sites with periwinkles; therefore, the climate data presented here may not represent climatic conditions throughout the nonnative ranges of periwinkles. Both species occur near Washington, DC, where the average daily temperature is 55.0 °F (12.8 °C) [94]. In Arkansas, periwinkles occur in an area with hot summers and moderately cool winters; only 4 days/year have snowfall >1.0 inch (2.5 cm). The first and last frosts in this region occur in early April and late October, respectively [55]. Bigleaf periwinkle occurs in the Huachuca Mountains, where mean daily temperatures are 79 °F (26 °C) in July and 48 °F (9 °C) in January [83]. Common periwinkle occurs on sites with mean daily temperatures in January as low as -7.8 °F (-22.1 °C) in New York [93], and in July as high as 82.2 °F (27.9 °C) in southwestern Georgia [100].
Annual rainfall is variable across the nonnative ranges of periwinkles.
Average annual rainfall for sites with periwinkles in their nonnative ranges Species Location Annual rainfall (mm) Both species Arkansas 1,080 [55] Washington, DC 1,114 [94] Bigleaf periwinkle Arizona 400 [83] North Carolina 1,417 [92] Common periwinkle Georgia 1,211 to 1,367 [100] Illinois 963 [88] New York 890 [93] West Virginia 1,209 [18]Periwinkles are somewhat drought tolerant; a review suggests that bigleaf periwinkle is more tolerant of drought than common periwinkle [79]. One review reports that hot, dry weather may cause bigleaf periwinkle death [7]. All bigleaf periwinkles in a greenhouse died after exposure to drying winds and intense heat (>100° F (38° C) for more than 10 days) [114]. Cold weather may damage bigleaf periwinkle (review by [7]), though one population in Ohio survived 2 of "the most severe winters of the past century, those of 1976 to 1977 and 1977 to 1978" [4].
Soils: Periwinkles are found on soils with a range of characteristics.
Parent material: Bigleaf periwinkle occurs on soils derived from granite, gneiss, or schist in Georgia [22]. In north-central Texas, it is associated with limestone [29].
Texture: In the Huachuca Mountains, bigleaf periwinkle occurs mainly on sandy-loam and sandy clay-loam riparian soils [83]. In its native range, common periwinkle is associated with soils of varying textures [35,44,53]. Common periwinkle occurs on silt loams in Ohio [58] and Illinois [88], clayey, loamy, and sandy soils in the Northeast [68], and rocky, sandy soil in Missouri [99].
Other soil characteristics: A review states that bigleaf periwinkle grows most vigorously in moist soil with only partial sun but may grow in deep shade with "poor" soil [7]. In Georgia, bigleaf periwinkle is associated with acidic clays [22]. Common periwinkle prefers moist sites [28,76,88], though it tolerates moderately well-drained soil [68]. While some sources suggest common periwinkle prefers fertile soil ([28], review by [25]), one source states that common periwinkle tolerates soils of low fertility [68]. In the oak-beech forest region of France, common periwinkle occurred on shallow soils ranging from 5.7 to 8.7 inches (14.4-22.1 cm) deep [35]. In its nonnative range, common periwinkle occurs on acid soils [18,68,88]. In France, common periwinkle occurred on soils with pH ranging from 6.7 to 7.2 [35].
Palatability and/or nutritional value: Periwinkles are generally unpalatable and have little nutritional value. Bigleaf periwinkle is listed as poisonous in South Africa [16]. Common periwinkle was an infrequent food item of the volcano rabbit in Mexico [20] and white-tailed deer in Indiana [91]. Caged Canada geese would not feed on common periwinkle, even when it was the only forage available [23].
Cover value: No information is available on this topic.
Bigleaf periwinkle generally flowers from March to June [4,29,42,78] but may bloom year-round in north-central Texas [29]. In the Carolinas bigleaf periwinkle produces fruit in June and July [78].
Common periwinkle generally flowers from between March and June depending on location [4,29,42,45,50,78,97]. In Georgia, most common periwinkle flowering occurs in early March, though flowering was observed as early as 28 February [40]. Common periwinkle fruits are produced from May to July in the southeastern United States ([78], review by [72]).
Documentation of periwinkle establishment by seed is rare. Bigleaf periwinkle seedlings were found in riparian areas in California [21], though seedlings are rarely found in the field (review by [7]). Documentation of common periwinkle seedlings was not found in the literature as of 2009.
Limitations to periwinkle growth have been infrequently documented. Bigleaf periwinkle growth is limited by dry or cold temperatures, and hot, dry weather may cause death (review by [7]). Bigleaf periwinkle was limited to shady areas of a riparian canyon bottom at the Ramsey Canyon Preserve (Gebow 2009 personal communication [41]).
The genus name for periwinkles is Vinca L. (Apocynaceae). This review summarizes information on the following periwinkle species [29,42,61,78,113]:
Vinca major L., bigleaf periwinkle
Vinca minor L., common periwinkle
In this review, species are referred to by their common names, and "periwinkles" refers to both species.
Vegetative regeneration is very important to the establishment and spread of both bigleaf ([74,113], reviews by [81,111]) and common ([66,88], review by [81]) periwinkles. Bigleaf periwinkle spreads with "great rapidity" by arching stolons, which root at the tips (review by [7]). Periwinkles form mats and extensive infestations even under forest canopies ([32], review by [72]). Given their ability to spread with the dumping of yard waste ([17,37], review by [10]), it is likely that periwinkles establish from plant fragments.
Bigleaf periwinkle grows in patches around the bases of trees or spreads up and down drainages through vegetative spread (review by [7]). In Belgium, common periwinkle distribution was not significantly clumped within forest patches despite its inability to disperse long distances (P>0.05) [56]. See Impacts for more information about vegetative rate of spread in periwinkles.
Stolons and roots of common periwinkle.
Vinca (/ˈvɪŋkə/;[2] Latin: vincire "to bind, fetter") is a genus of flowering plants in the family Apocynaceae, native to Europe, northwest Africa and southwest Asia.[3][4][5][6] The English name periwinkle is shared with the related genus Catharanthus (and also with the common seashore mollusc, Littorina littorea).
Vinca plants are subshrubs or herbaceous, and have slender trailing stems 1–2 m (3.3–6.6 ft) long but not growing more than 20–70 cm (8–27.5 in) above ground; the stems frequently take root where they touch the ground, enabling the plant to spread widely. The leaves are opposite, simple broad lanceolate to ovate, 1–9 cm (0.5–3.5 in) long and 0.5–6 cm (0.20–2.36 in) broad; they are evergreen in four species, but deciduous in the herbaceous V. herbacea, which dies back to the root system in winter.[7][8]
The flowers, produced through most of the growing season, are salverform (like those of Phlox), simple, 2.5–7 cm (0.98–2.76 in) broad, with five usually violet (occasionally white) petals joined together at the base to form a tube. The fruit consists of a pair of divergent follicles; the dry fruit dehisces along one rupture site to release seeds.[7][8]
Two of the species, Vinca major and Vinca minor, are extensively cultivated as a flowering evergreen ornamental plant. Because the plants are low and spread quickly, they are often used as groundcover in garden landscapes and container gardens. They are also traditionally used in older cemeteries as an evergreen maintenance-free ground cover.[9] Many cultivars are available, with different plant, leaf, and flower colors, sizes, and habits.
Although attractive, both Vinca major and Vinca minor may be invasive in some regions where they are introduced species because the rapid spreading chokes out native plant species and alters habitats. Areas affected include parts of Australia, New Zealand, Canada, and the United States, especially coastal California.[10][11]
The vinca alkaloids include at least 86 alkaloids extracted from plants in the genus Vinca.[12][13][14] The chemotherapy agent vincristine is extracted from a closely related species, Catharanthus roseus,[15][16][17] and is used to treat some leukemias,[18] lymphomas,[19] and childhood cancers,[20] as well as several other types of cancer and some non-cancerous conditions. Vinblastine is a chemical analogue of vincristine[13][16][21] and is also used to treat various forms of cancer.[22] Dimeric alkaloids such as vincristine and vinblastine are produced by the coupling the smaller indole alkaloids vindoline and catharanthine.[13][23] In addition, the nootropic agent vincamine is derived from Vinca minor. Vinorelbine, a newer semi-synthetic chemotherapeutic agent, is used in the treatment of non-small-cell lung cancer[16][24] and is prepared either from the natural products leurosine[25][26] or catharanthine and vindoline,[16][27] in both cases by first preparing anhydrovinblastine.[15][16][27]
Accepted species:[1]
{{cite web}}: CS1 maint: url-status (link) Vinca (/ˈvɪŋkə/; Latin: vincire "to bind, fetter") is a genus of flowering plants in the family Apocynaceae, native to Europe, northwest Africa and southwest Asia. The English name periwinkle is shared with the related genus Catharanthus (and also with the common seashore mollusc, Littorina littorea).
