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Species
Berberis thunbergii var. minor
IUCN
NCBI
EOL Text
Japanese barberry occurs and is reported to be invasive throughout the northeastern U.S. from Maine to North Carolina and west to Wisconsin and Missouri. It grows well in full sun to deep shade and forms dense stands in closed canopy forests, open woodlands, wetlands, fields and other areas.
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/beth.htm |
More info for the terms: cover, density, invasive species, shrubs, swamp
Phenology of Japanese barberry at the time of burning may have an impact on its postfire
recovery. Richburg and others [86,88] evaluated the effectiveness of applying cutting and
burning treatments at different times of year in reducing sprout "vigor" for 7
woody invasive species including Japanese barberry. All treatments, regardless of timing,
reduced Japanese barberry cover for over 1 year, with a decrease of nearly 90% in treatments
that included a burn [86,88]. Japanese barberry sprout height, biomass, and density were
generally similar between cut plots and burned plots but were not compared to control plots [88].
Although differences were not significant, total nonstructural carbohydrate (TNC) levels
were lower than controls in the April-treated Japanese barberry and remained depleted
throughout the growing season. Any depleted TNC in treated plants returned to levels
comparable to those of the control plots after 1 growing season without treatments. Species
richness did not appear to be affected by treatments [86].
In the Berkshire region of western Massachusetts, Japanese barberry occurs on 2
parcels owned by The Nature Conservancy: The Bartholomew site is a mature deciduous forest
dominated by sugar maple, black birch, and white ash, with an understory dominated by
Japanese barberry, with an average cover of 70%. No other species had a cover value above
10% in Japanese barberry thickets. The Bear Rock site is a forested swamp dominated by white
ash and red maple with an understory dominated by Morrow's honeysuckle with Japanese barberry
and other nonnative shrubs as common associates. Four plots at each site were randomly assigned
to 1 of 4 understory treatments in 2001: 1) untreated control, 2) dormant-season burn (or cut
if unable to burn), 3) growing-season cut and burn combination, and 4) repeated growing-season
cuts. All growing-season treatments were cut again in 2002. The "dormant-season" burn
at the Bartholomew site was conducted on 19 April 2002, after leaf-out of Japanese barberry.
Therefore, this should be considered a growing-season treatment for Japanese barberry.
Researchers were unable to ignite Japanese barberry slash in treated stands during the growing
season (August). However, burning was accomplished in November of the same year [86,88].
Following treatments at the Bartholomew site, Japanese barberry cover decreased to less
than 6% in the plots that included burning, but only decreased by about one-third (to 23% cover)
in the cut-only plot. At the Bear Rock site, Japanese barberry cover declined following
treatments, with the greatest declines in growing-season-treated plots [86,88].
Percent cover of Japanese barberry before and after cutting and burning treatments at 2 sites in Massachusetts [86,88] |
|||||
Site |
Year measured |
Treatments (dates) |
|||
Control |
Cut (6 July 2001) |
Cut (6 July 2001) |
Burn |
||
Bartholomew (upland forest) | 2001* | 80.9 | 83.3 | 85.9 | 31.3 |
2003** | 72.5 | 5.1 | 23.3 | 2.9 | |
Control |
Cut (10 July 2001) Burn (18 Nov 2001) Cut (13 June 2002) Cut (24 July 2002) |
Cut (10 July 2001) Cut (13 June 2002) Cut (24 July 2002) |
Cut (12 April 2002) |
||
Bear Rock (forested swamp) |
2001 | 4.2 | 7.1 | 12.2 | 2.9 |
2003 | 4.8 | 0.7 | 3.7 | 1.4 | |
*Pretreatment measures conducted prior to initial treatment. **Posttreatment measures conducted 20 August and 21 September. |
Japanese barberry sprout height, biomass, and density were compared among
treated plots but were not compared to control plots. At Bear Rock, Japanese
barberry sprout heights were generally similar on growing-season treatment
plots, while the dormant-season cut had the tallest sprout heights [88]. Dormant-
season-treated Japanese barberry plants had more than 6 times the biomass of the
growing-season-treated plants, a result that cannot be explained solely by the
difference in amount of growing time before harvest. Japanese barberry sprout
density was similar among all treated sites [88].
Although differences were not significant, TNC levels were lower than controls
in April-treated Japanese barberry and remained depleted throughout the growing
season. TNC levels in treated plants returned to levels similar to those in untreated
control plants after 1 growing season without treatments [86,88].
Species richness and understory species cover did not change at the Bartholomew
site after treatment. Richness values were not given for the Bear Rock site [86,88].
Species richness (number of species) before and after cutting and burning treatments at Bartholomew [86,88] |
|||||
Site |
Year measured |
Treatments (dates) |
|||
Control |
Cut (6 July 2001) |
Cut (6 July 2001) |
Burn |
||
Bartholomew | 2001* | 43 | 44 | 32 | 47 |
2003** | 44 | 45 | 27 | 43 | |
*Pretreatment measures conducted prior to initial treatment. **Posttreatment measures conducted 20 August and 21 September. |
More info for the term: shrubs
Climate change: Studies and related models from
oak-dominated, second-growth, Japanese barberry-invaded forests in the northeastern United
States suggest possible implications of global warming in these communities. The investigators
suggest that warming in southern New York would benefit the net carbon gain of mountain-laurel
relative to Japanese barberry and may therefore limit the displacement of native shrubs by
Japanese barberry. Conversely, increased regional nitrogen deposition along with pronounced
winter warming may enhance carbon gain in Japanese barberry relative to native shrubs and
contribute to Japanese barberry invasiveness. More information is needed to determine the role
that climate change may play in Japanese barberry invasion in northeastern deciduous forests.
Models based on these data predict that the annual foliar carbon loss has increased since the
early 20th century by 12.9%, 10.3%, and 8.9% for Japanese barberry, mountain-laurel, and highbush
blueberry, respectively [118,119,120]. See the Seasonal Development section for more details of this research.
Japan
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/beth.htm |
More info for the terms: cover, frequency, prescribed fire, relative frequency, root crown
Japanese barberry is likely to sprout from the root crown or rhizomes after fire or other top-killing event, as was observed after prescribed burning and cutting treatments in Massachusetts forests [86,88] and after cutting treatments without burning in Maine [14]. A review by Huebner [41] suggests that Japanese barberry is likely to survive low-severity fire and maintain its population size after a burn, but that it may be reduced in community importance after repeated (annually consecutive for at least 2 to 5 years), growing-season (spring to early summer) fires. Similarly, a review by Johnson [45] suggests that prescribed fire has successfully reduced Japanese barberry populations in midwestern oak savannas. Japanese barberry response to prescribed fires in oak savannas or repeated prescribed fires are not documented elsewhere in the available literature as of 2008.
Japanese barberry can probably establish after fire from off-site seed sources and possibly from the soil seed bank as suggested by Huebner [41], although seed banking information is limited and suggests that substantial seed banking is lacking for this species. One study reports establishment of Japanese barberry 4 years after a prescribed fire in a mature stand of red pine (Pinus resinosa) and eastern white pine (Pinus strobus) in Michigan. Japanese barberry seedlings were absent from all plots subject to biennial burning (1991, 1993, and 1995) when sampled in 1994 and 1995, and were absent from once-burned (in 1991) and unburned control plots in 1994. In 1995, Japanese barberry occurred at 0.9% relative frequency and 0.33% cover on once-burned plots and at 0.4% relative frequency and 0.03% cover on unburned control plots [77].
More info for the terms: fire management, invasive species, natural, presence, restoration, shrub, shrubs
Impacts: Information regarding Japanese barberry impacts in invaded communities includes evidence that Japanese barberry invasion displaces native shrubs [52] and causes changes in soil properties (see Soil characteristics and feedback loops). On a study site in northern New Jersey dominated by Japanese barberry, the native understory shrubs deerberry and hillside blueberry were significantly (P<0.05) less abundant than on uninvaded sites [52]. Japanese barberry persistence in invaded stands may also alter successional patterns (see Successional Status).
Japanese barberry invasion can alter soil microbial composition and increase nitrate concentrations [51,53,55]. High nitrate concentrations may result in higher nitrogen losses due to leaching or might make these sites more susceptible to invasion by other weedy plants. The researchers suggest that even if Japanese barberry is removed, "it is very likely that differences in the soils will persist for a prolonged period after that, which might significantly impede the restoration of native flora in the cleared sites" [54].
One study also provides evidence that invaded sites support more biomass in the shrub layer than uninvaded sites [29]. There is concern that additional biomass in invaded stands may increase the likelihood of fire in those stands [21] (see Fuels), although this did not seem to be the case during the growing season on sites studied in Massachusetts [86,88] (see Fire Management Considerations).
Control: Information presented in the following sections comes primarily from literature reviews and may not be comprehensive. It is intended to contribute to understanding disturbance adaptations of Japanese barberry and to present considerations for the context of fire management. For more detailed information on control of Japanese barberry, go to individual references cited here or to local extension services.
Japanese barberry may be best controlled by preventing its establishment and by eliminating small, newly expanding populations [92]. Individual Japanese barberry plants may be controlled by handpulling or digging, as it has a shallow root system [45,100]. However, this method is difficult and time consuming [92] and it is important to remove as much of the underground material as possible because Japanese barberry is likely to sprout from rhizomes left in the soil. Sprouts may be controlled by pulling or herbicide applications [45]. Pulling common barberry in the early 1900s effectively eradicated it from many sites [92].
Japanese barberry is especially easy to see in the winter and early spring before deciduous plants leaf out. If plants have fruit present, they should be bagged and disposed of to prevent seed dispersal [95].
Prevention: Prohibiting the commercial sale and planting of Japanese barberry may help limit the establishment and spread of new populations [92]. Native alternatives include coastal sweet pepperbush (Clethra alnifolia) and northern spicebush (Lindera benzoin) [100].
Observations by Ehrenfeld [26] suggest that Japanese barberry spreads into relatively undisturbed forests from forest edges. Forest reserves less than 2,400 to 4,900 acres (1,000-2,000 ha) in size would be especially vulnerable to invasion because of their large perimeter to area ratios [26]. Maintaining large forest and natural areas uninterrupted by roads and development may help prevent the establishment and spread of Japanese barberry and other invasive species.
Integrated management: Information on integrating mechanical control (cutting) with prescribed burning is presented in the Fire Management Considerations section. Some combinations of mechanical and chemical control are described in the following sections.
Physical/mechanical: Handpulling is an effective method of reducing Japanese barberry populations and seed production, and it can be done during most of the year. It is most effective for small Japanese barberry plants and small populations [95]. Older shrubs can be dug when soil is moist [100]. When pulling Japanese barberry by hand or removing by other mechanical methods, it is important to remove as much of the root system as possible and to minimize soil disturbance [45,95]. Shrubs can be cut at the base in winter or spring instead of digging, and herbicide can then be used on resprouts. Once removed from old field habitats, regular mowing may prevent reestablishment [45,100]. Repeated mowing or cutting controls the spread of Japanese barberry but does not eradicate it. Stems need to be cut at least once per growing season, as close to ground level as possible. Hand-cutting of established clumps is difficult and time consuming due to the long, arching stems and prolific thorns [95].
Fire: See Fire Management Considerations.
Biological: A review by Silander and Klepis [92] suggests that there may be some potential for biological control of Japanese barberry using nonnative tephritid flies, though the potential for biocontrol has not been studied for this species in North America.
Chemical: Treatment with systemic herbicides like glyphosate and triclopyr has been effective for controlling Japanese barberry (review by [100]). The Southeast Exotic Pest Plant Council [95] suggests that large thickets of Japanese barberry may be foliar sprayed with herbicides such as glyphosate or triclopyr in areas where risk to nontarget species is minimal. They recommend using the cut-stump method (cutting stems at or near ground level and applying herbicide to the stump) when the ground is not frozen. The cut-stump method is especially useful where the presence of desirable species precludes foliar application. Glyphosate is most effective for controlling Japanese barberry when applied in early spring at leaf out, when little else is in leaf [92].
Cultural: No information is available on this topic.
introduced; N.B., N.S., Ont., P.E.I.; Conn., Del., Ga., Ill., Ind., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Minn., Mo., Nebr., N.H., N.J., N.Y., N.C., Ohio, Pa., S.Dak., Vt., Va., W.Va., Wis., Wyo.; native, Asia (Japan).
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Rights holder/Author | eFloras.org Copyright © Missouri Botanical Garden |
Source | http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=233500242 |
As of this writing (2008), no accounts in available literature describe immediate effects of fire on Japanese barberry. Fire likely only top-kills Japanese barberry and does little damage to belowground organs, based on a single field study describing its postfire response [86,88]. It is possible that severe fire may kill entire plants, although this is not documented. No information was available on fire effects on or heat tolerance of Japanese barberry seed.
Do not plant Japanese or European barberry. No biological control is available for this plant. Wearing thick gloves to protect from spines, young plants can be pulled up by hand. A Weed Wrench® can be used to uproot older shrubs when soil is moist. Shrubs can also be mowed or cut repeatedly. Treatment with systemic herbicides like glyphosate and triclopyr has been very effective.
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/beth.htm |
Chile Central
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Rights holder/Author | Pablo Gutierrez, IABIN |
Source | No source database. |