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Magnoliopsida
Lonicera japonica Thunb.
EOL Text
Lonicera japonica Thunberg in Murray, Syst. Veg., ed. 14. 216. 1784.
Japanese Honeysuckle, Chinese Honeysuckle, 忍冬 ren dong
Climbers, semievergreen. Branches becoming hollow. Branches, petioles, and peduncles with dense, yellow-brown spreading stiff hairs, interspersed with long glandular hairs. Petiole 3-8 mm; leaf blade ovate or oblong to lanceolate, 3-8 × 1.5-4 cm, abaxially sparsely to densely hairy, adaxially hairy along veins, base rounded to subcordate, margin ciliate, occasionally sinuate, apex acute to acuminate. Flowers fragrant, paired and axillary toward apices of branchlets; peduncle 2-40 mm, shorter toward apex of branchlets; bracts leaflike, ovate to elliptic, 1-3 cm; bracteoles ca. 1 mm, pubescent, apex rounded or truncate and ciliate. Neighboring 2 ovaries free; ovary ca. 2 mm, glabrous. Calyx lobes triangular, ca. 1 mm, densely hairy abaxially and along margin, apex acute. Corolla bilabiate, white, becoming yellow, or purple outside and white inside, 3-5 cm, spreading hairy with interspersed long glandular hairs outside; tube 1.5-3 cm, not gibbous at base; upper lip irregularly 4-lobed, lobes 2-8 mm; lower lip recurved. Stamens and style glabrous, subequaling to exceeding corolla. Berries black when mature, glossy, globose, 6-7 mm in diam.; seeds brown, ovoid or ellipsoid, ca. 3 mm, shallowly pitted. Fl. Apr-Jun, fr. Oct-Nov. 2n = 18*.
Scrub, sparse forests, mountain slopes, stony places, roadsides; (800-)1500 m. China: Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, Yunnan, Zhejiang; Japan; Korea [also widely cultivated in SE Asia; introduced and invasive in Australasia, Europe, North America].
Two varieties:
* Lonicera japonica var. chinensis (Watson) Baker: Corolla purple outside, white inside. China: Anhui, ?Guizhou, ?Zhejiang.
* Lonicera japonica var. japonica: Corolla white, later yellow-white. China: Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hebei, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, Xinjiang, Yunnan, Zhejiang; Japan; Korea.
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | Michаel Frаnkis, Michаel Frаnkis |
Source | No source database. |
Japanese honeysuckle was introduced to Long Island, New York, in 1806 for ornamental, erosion control and wildlife uses.
License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
Rights holder/Author | U.S. National Park Service |
Source | http://www.nps.gov/plants/alien/pubs/midatlantic/loja.htm |
Japan and Korea
Comments: Lonicera japonica is generally associated with disturbance and has spread to old fields, roadsides, fence rows, prairies, sand barrens and forest openings. In Pennsylvania, it is a major component of the third stage of succession in old fields, increasing after fields have been abandoned for four years (Keever 1979). Light appears to be the major limiting factor (Andrews 1919, Leatherman 1955, Thomas 1974), but recent studies suggest that Japanese honeysuckle can invade established woodlands when natural processes such as storms or Dutch elm disease create canopy openings (Thomas 1974, Slezak 1976). Invasion is particularly effective in moist woodlands and floodplain forests (Andrew 1919, Snyder pers. comm., Wistendahl 1958). Slezak (1976) found that in poorly drained areas the frequency of Japanese honeysuckle decreased with increasing canopy closure and understory closure had no significant effect. In well-drained areas, however, the frequency of Japanese honeysuckle was inversely correlated with closure of the subcanopy, but canopy coverage was not correlated with honeysuckle frequency (Slezak 1976). Japanese honeysuckle is one of the few species that can withstand pollution from heavy metals and SO2 (Caiazza and Quinn 1980).
Infestations have reached pest proportions in areas with annual precipitation of at least 100 cm and mean January temperatures of at least -1 C and freezing January night temperatures at least 5% of the nights (Leatherman 1955).
No discussion of the habitat of Japanese honeysuckle would be complete without mentioning that Lonicera japonica is still being propagated and promoted for use as a groundcover in areas where it has not reached pest proportions.
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | NatureServe |
Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Lonicera+japonica |
The preference is partial sun, moist to mesic conditions, and a fertile loam to support the rampant growth. This vine is very aggressive; it can easily smother shrubs and small trees.
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | Copyright © 2002-2014 by Dr. John Hilty |
Source | http://www.illinoiswildflowers.info/weeds/plants/jp_honeysuckle.htm |
Japanese honeysuckle is one of the most recognizable and well established ornamental vines in the U.S. It is documented to occur and reported to be invasive throughout the eastern U.S. from Maine to Florida and west to Wisconsin and Texas, with scattered occurrences in the Southwest. It is adapted to a wide variety of habitats from full sun to shade.
License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
Rights holder/Author | U.S. National Park Service |
Source | http://www.nps.gov/plants/alien/pubs/midatlantic/loja.htm |
More info for the terms: peat, xeric
Japanese honeysuckle occurs on a variety of sites within its North American range. It is most common locally in areas where it was previously planted for hedges, erosion control, wildlife habitat, or ornamental purposes [57].
Disturbance is an important site characteristic promoting the establishment and success of Japanese honeysuckle. It is capable of invading "openings" within a variety of sites in eastern North America, either by seedling germination or vegetative spread [70]. Japanese honeysuckle is most prolific at forest edges and in open areas, but can persist under a closed forest canopy [93]. It often invades forests where there is moderate disturbance of vertical structure, allowing more light into the understory. Overstory removal is not a necessary precondition for invasion, although Japanese honeysuckle biomass production is greatest where "vertical-structure disturbance" is greatest [134]. For more information regarding the invasive nature of Japanese honeysuckle see Impacts.
Leatherman [70] characterized the distribution of "naturalized" Japanese honeysuckle in eastern North America as generally south of an isotherm where mean January temperature is 30 degrees Fahrenheit (-1° C), north of an isotherm where only 5% of January daily low temperatures are < 32 degrees Fahrenheit (0° C), and east of the 40-inch (1,016 mm) mean annual precipitation limit. Northern distribution is limited by a short growing season and late spring frosts that damage new growth [47,96]. Projected future climate change has led to speculation that Japanese honeysuckle may expand its northern range [111]. Southern distribution may be limited by mild winter temperatures that are insufficient for seed stratification. Japanese honeysuckle generally is not invasive in prairie or grassland sites [70].
Distribution of Japanese honeysuckle based on elevation is varied. In the northeastern United States (Pennsylvania, New York, and northward), it is rarely found above 1,200 feet (360 m). It grows at higher elevations in the southern Appalachians (observed at 5,000 feet (1,500 m) in North Carolina) and Ozarks (2,800 feet (840 m) in Arkansas) [70]. Japanese honeysuckle occurs between 4,500 and 7,000 feet (1,350-2,100 m) in New Mexico [73] and generally below 3,300 feet (1,000 m) in California [53].
Japanese honeysuckle occurs on a variety of soil types, but is "noticeably absent" on coarse sands and poor peat soils [57]. Distribution may be limited on xeric sites with coarse, well-drained, infertile soils on the southeastern coastal plain. It is likely that extensive areas of poorly drained soils contribute to the absence of invasive Japanese honeysuckle in southern Florida [70].
More info on this topic.
More info for the terms: cover, formation, frequency, natural, shrub, succession
While Japanese honeysuckle is found within a variety of successional stages in eastern North America, it seems to occur in the greatest densities in early-successional habitats such as old fields and shrub thickets [108]. It can be found in, and sometimes dominates, abandoned agricultural fields in early stages of succession [62]. Japanese honeysuckle displayed the highest relative cover and greatest frequency of any plant species 10 years after hurricane-related debris avalanches in the Blue Ridge Mountains of Virginia [55]. It appears that Japanese honeysuckle benefits from a combination of available light and small-diameter vertical structure, conditions commonly found in recently disturbed habitats.
Despite its relative affinity for open habitats, Japanese honeysuckle also has the ability to spread extensively within mature forest, persisting for many years in the understory until disturbance creates a gap in the canopy. It occurs in the understory of old-growth red river bottom forests in the Southeast [121]. In the New Jersey piedmont, it can be found within old-growth oak forest, thought to be unburned and uncut for >250 years. Japanese honeysuckle rapidly invades gaps following the natural fall of very large, mature trees [66]. If present at the time of gap formation, it can respond with vigorous growth, potentially dominating understory strata [66,124].
Dense concentrations of Japanese honeysuckle can inhibit regeneration of woody forest species. This may lead to a "disturbance climax" where succession is altered and the community is maintained as a virtual Japanese honeysuckle monoculture [47]. Forest management activities that remove part or all of the overstory can enhance opportunities for Japanese honeysuckle, frequently at the expense of desirable native and/or commercial species. For example, Japanese honeysuckle production in southeastern forests is frequently stimulated by silvicultural thinning in mixed pine/hardwood stands [95].
The ability of Japanese honeysuckle to establish and persist in later-successional stages of various eastern forests partly depends upon its ability to tolerate shade. Japanese honeysuckle plants in eastern Texas showed signs of stress after 2 years' growth under 8% of ambient light. While new growth was initiated each spring, leaders would subsequently die back and a portion of the current leaf crop would abscise following maturation of the flush [13]. Other reports indicate a greater tolerance to shade than is indicated above. Japanese honeysuckle can reportedly survive substantial periods of "extreme shade," although growth is reduced [8,124]. Favorable conditions can occur in understory environments where carbon gain is enhanced by the utilization of ephemeral sunflecks [24,124]. Slezak [124] indicated that vigorous growth occurs under conditions of >3% of full sunlight. In a greenhouse experiment, Japanese honeysuckle had a light compensation point (the irradiance level where net photosynthesis = 0) of about 0.9% of full sunlight. Average survival rates were >60% at 2% of full sunlight and 100% at 3.5% of full sunlight. Biomass accumulation increased substantially within this range [8]. Newly established plants may be less shade tolerant than mature plants. The following table provides data concerning the shade tolerance of rooted cuttings grown outdoors in containers, with shade treatments using different layers of cheesecloth [70].
% of full sun | 100 | 50 | 25 | 10 | 5 |
number of plants surviving (out of 10) after 160 days | 7 | 8 | 8 | 5 | 1 |
More research is needed to help understand the role of shade tolerance, relative to other factors, in determining the ability of Japanese honeysuckle to establish, compete, and persist in forested habitats.
More info for the terms: cover, fresh, mast
Japanese honeysuckle is an important browse species for white-tailed deer throughout much of the eastern and southern United States, especially during poor mast years and in winter when other food sources are scarce or inaccessible [43,49,79,87,109,116,125]. It is particularly important for white-tailed deer in the South. Japanese honeysuckle is considered a "choice" woody browse species for white-tailed deer on the Oconee National Forest in the Georgia Piedmont [48]. In areas of northern Alabama managed primarily for loblolly pine production, Japanese honeysuckle constituted 49.4% of the year-round diet of white-tailed deer. No other single food item amounted to >6% [122]. Cultivation and fertilization of Japanese honeysuckle food plots may provide winter forage for white-tailed deer in the southeastern United States [116,130], although such practices have been discouraged [117].
In eastern forests, wild turkeys, northern bobwhite, and various songbirds utilize Japanese honeysuckle as food, particularly during winter when other food may be scarce [45,56,79,126]. Its persistent leaves shield fruit from sleet when other food is glazed with ice [45]. Wood thrushes, hermit thrushes, tufted titmice, dark-eyed juncos, eastern bluebirds, purple finches, pine grosbeaks, American robins, white-throated sparrows, and yellow-rumped warblers consume fruits [46,56,96,97,132]. Japanese honeysuckle also provides excellent forage for rabbits [79]. Ruby-throated hummingbirds feed from the flowers [126].
Palatability/nutritional value:
Caloric value of fruits has been measured at 4,419 cal/g [20] and 374 Calories/pulp of 1 fruit [98].
Nutritional value and palatability of leaves remain relatively high throughout winter [14].
The following table provides some nutritional information for Japanese honeysuckle taken from cultivated white-tailed deer food plots in northern Arkansas. Data are leaves / twigs [109].
Summer | Fall | Winter | Spring | |
crude protein (% dry weight) | 12 / 5 | 14 / 5.5 | 13 / 5 | 16 / 7.5 |
calcium (% dry weight) | 1.6* / 0.45 | 1.3 / 0.55 | 1.5* / 0.7* | 1.4* / 0.6* |
phosphorus (% dry weight) | 0.22 / 0.19 | 0.245 / 0.115 | 0.205 / 0.095 | 0.22 / 0.15 |
dry matter digestibility (%) | 89.5 / 40.5 | 89.5 / 33.5 | 91.5 / 34 | 91 / 51 |
All values are the average of data from 2 consecutive seasons except where noted (*), which are a single season.
The following table provides some nutritional information for Japanese honeysuckle leaves grown under 3 different light levels in eastern Texas1. While leaf nutrient concentrations generally increased with shading, digestibility diminished with decreased light intensity [14].
% Shade | April | May | June | July | August | September | December | |
Crude Protein2 | 0 | 12c | 10c | 9c | 9c | 9c | 8c | 10c |
55 | 19b | 15b | 15b | 14b | 15b | 15b | 17b | |
92 | 21a | 18a | 17a | 16a | 17a | 18a | 18a | |
Phosphorus3 | 0 | 0.21b | 0.14b | 0.12b | 0.14b | 0.15b | 0.12b | 0.13c |
55 | 0.34a | 0.28a | 0.25a | 0.26a | 0.24a | 0.24a | 0.22b | |
92 | 0.34a | .026a | 0.26a | 0.29a | 0.29a | 0.30a | 0.29a | |
Calcium3 | 0 | 0.65b | 0.84b | 0.95b | 0.94b | 1.01b | 1.04b | 1.06b |
55 | 0.78b | 0.86b | 0.88b | 0.86b | 0.91b | 0.96b | 0.99b | |
92 | 1.18a | 1.24a | 1.27a | 1.26a | 1.25a | 1.25a | 1.28a | |
Acid-Detergent Fiber3 | 0 | 18c | 18c | 22c | 23c | 23c | 22c | 19c |
55 | 23b | 24b | 27b | 28b | 27b | 26b | 24b | |
92 | 30a | 31a | 34a | 35a | 35a | 35a | 35a | |
Apparent Digestible Energy4 | 0 | 3130a | 3150a | 2960a | 2950a | 2920a | 3090a | 3090a |
55 | 2640b | 2700b | 2450b | 2340b | 2290b | 2490b | 2580b | |
92 | 1760c | 1900c | 1920c | 1570c | 1610c | 1550c | 1630c | |
In Vivo Dry-Matter Digestibility3 | 0 | 69a | 70a | 65a | 66a | 65a | 67a | 66a |
55 | 58b | 59b | 54b | 51b | 51b | 55b | 55b | |
92 | 39c | 43c | 42c | 35c | 36c | 35c | 37c |
1 Values associated with shade intensities for each species and month combination followed by a common letter do not differ statistically (p<0.05).
2% of fresh tissue
3 % of oven-dry matter
4 calories/g
Cover value: Japanese honeysuckle thickets provide cover for eastern cottontails, northern bobwhite, wild turkeys, and songbirds [45,79]. Northern bobwhite nest in Japanese honeysuckle thickets in southern Illinois [29]. Japanese honeysuckle thickets may provide bedding cover for white-tailed deer [87], and good habitat for cotton rats [15].