Skaneateles Conservation Area/Invasive species/Lonicera

<< Prohibited invasive plants at the SCA

Lonicera spp. (non-native bush honeysuckles)

edit

The Eurasian bush honeysuckle species most likely to be present at the SCA (in approximate order of likelihood) are:

  • Lonicera morrowii (Morrow’s honeysuckle),
  • Lonicera × bella [L. morrowii × tatarica] (Bell’s honeysuckle),
  • Lonicera tatarica (Tartarian honeysuckle), and
  • Lonicera maackii (Amur honeysuckle)

These exotic honeysuckles are all similar in appearance and invasive characteristics and displace valuable natives.[1]

All four of these taxa are grouped in what is now called Lonicera subg. Lonicera sect. Lonicera (syn. sect. Coeloxylosteum sensu Rehder).[2]

Section Lonicera is characterized by flowers with a two-lipped corolla and hollow branches.[3]

This section also contains native "fly honeysuckles," of which Lonicera canadensis (American fly-honeysuckle) is known to be present at the SCA.[4]

Description

edit

All of the above honeysuckles are upright deciduous shrubs with long arching branches, and commonly reach 5 to 20 feet tall. They are all in the Lonicera section Lonicera[1] and produce abundant red to orange-yellow fruit.[2][3]

Table 1. Bush honeysuckle differentiation
Species Common name Leaf texture Leaf shape Mature (2 yr)
stem pith
Fruit shape Fruit color Corolla Style Peduncle
length
Nativity
Lonicera morrowii Morrow's honeysuckle densely hairy
(top and bottom)
oblong
elliptic
hollow,
darker
round in pairs yellow, orange, or red lobed nearly to base
zygomorphic
10-22 mm long
pubescent ≤ 15 mm non-native
(invasive)
Lonicera × bella
 [L. morrowii × tatarica]
Bell’s honeysuckle densely hairy below,
sparsely hairy above
hollow,
darker
round in pairs yellow, orange, or red lobed nearly to base
zygomorphic
10-22 mm long
pubescent 5 - 15 mm non-native
(invasive)
Lonicera tatarica Tartarian honeysuckle smooth, hairless oblong
ovate
hollow,
darker
round in pairs yellow, orange, or red lobed nearly to base
zygomorphic
10-22 mm long
pubescent non-native
(invasive)
Lonicera maackii Amur honeysuckle abruptly
acuminate
hollow,
darker
round in pairs yellow, orange, or red bilabiate
zygomorphic
10-22 mm long
pubescent < 5 mm non-native
(invasive)
Lonicera canadensis American fly honeysuckle solid white
not hollow
round in pairs bright red ± actinomorphic
10-22 mm long
short spur at the base
glabrous native

Note: The native Lonicera canadensis (American fly honeysuckle) is also present at the SCA and looks superficially similar to the exotic bush honeysuckles, so care must be taken before removing any plant. A simple but not definitive way to tell the difference is that the European honeysuckles may have hollow or dark piths, while native honeysuckles have solid white pith.

Eurasian bush honeysuckles are some of the first shrubs to leaf out in the spring, which allows them to shade native plants and encourages birds to nest earlier and lower to the ground, where they are more vulnerable to predators.[4]

Second to European buckthorn, Eurasian bush honeysuckles, are probably the dominant shrub seen on most of the SCA.[5]

In fact the two shrubs (buckthorn and honeysuckle) are sometimes referred to collectively using the colloquial term "bucksuckle,"[6][7] which locally has broadened to refer collectively to all common invasive shrubs and even to be used as a verb indicating the removal of any such invasive plants.

Invasiveness ranking of Lonicera × bella complex

edit

The 2008 relative maximum invasiveness score for the complex containing Lonicera morrowii, L. tatarica & L. × bella (exotic bush honeysuckles) was 85.54%.[1]

All species of the Lonicera × bella complex are prohibited by New York State law.[2]

Ecological impact

edit

Dense patches of Lonicera morrowii can cover 100% of an infested forest understory.[3]

Forest regeneration following disturbance can be severely impeded by these species, which displace and suppress native species.[4]

The L. × bella complex is an aggressive invader of lower elevation forests throughout the northeastern United States.[5]

Red carotenoid pigment (rhodoxanthin) in the fruits of Lonicera morrowii were found to cause the terminal tail bands on cedar waxwings (Bombycilla cedrorum) to change color from yellow to orange.[6]

Biological characteristics and dispersal ability

edit

A high percentages of seeds of L. morrowii (78–97%) germinate, both under litter and beneath the soil surface.[7]

Even though the fruit (as of introduced species in general) is of low quality, it is eaten and dispersed by both birds and mammals.[8][6]

Ecological amplitude and distribution

edit

Exotic bush honeysuckle invades wetlands, including shrub swamps, forested wetlands, riparian zones, and ditches. It also invades upland grasslands, shrublands, forests, woodlands, and roadsides.[1]

Dense patches often cover 100% of and area.[3]

Studies are mixed on its ability to colonized well-forested areas. It's clear that it can co-dominate old fields and early-successional forest communities, but may decline as forests mature (if they are allowed to).[9]

Difficulty of control

edit

Exotic bush honeysuckles are perennial shrubs that readily resprout from roots.[4]

  1. a b M.J. Jordan, G. Moore & T.W. Weldy (2008). Invasiveness ranking system for non-native plants of New York. Unpublished. The Nature Conservancy, Cold Spring Harbor, NY; Brooklyn Botanic Garden, Brooklyn, NY; The Nature Conservancy, Albany, NY. Lonicera × bella complex assessed by Steve Clemants, Gerry Moore, August 13, 2008.
  2. New York Codes, Rules and Regulations, Title 6 Section 575.3 - Prohibited invasive species
  3. a b John C. Hunter and Jennifer A. Mattice (2002). "The Spread of Woody Exotics into the Forests of a Northeastern Landscape, 1938-1999." The Journal of the Torrey Botanical Society, Jul. - Sep., 2002, Vol. 129, No. 3 (Jul. - Sep., 2002), pp. 220-227. Torrey Botanical Society.
  4. a b M.S.Batcher & S.A.Stiles (2000). Element stewardship abstract for the bush honeysuckles. The Nature Conservancy, Arlington, VA.
  5. K.Woods (1993). "Effects of invasion by Lonicera tatarica L. on herbs and tree seedlings in four New England forests." American Midland Naturalist. 130(1): 62-74.
  6. a b Mark C. Witmer (1996). "Consequences of an Alien Shrub on the Plumage Coloration and Ecology of Cedar Waxwings." The Auk, Volume 113, Issue 4, 1 October 1996, Pages 735–743.
  7. Siti N. Hidayati, Jerry M. Baskin & Carol C. Baskin (2000). "Dormancy-breaking and germination requirements of seeds of four Lonicera species (Caprifoliaceae) with underdeveloped spatulate embryos." Seed Science Research 10: 459-469.
  8. Douglas W. White and Edmund W. Stiles (1992). "Bird dispersal of fruits of species introduced into eastern North America." Canadian Journal of Botany. 70(8): 1689-1696.
  9. Richard S. Mitchell & Gordon C. Tucker. (1994) "Flora of an Unusually Diverse Virgin and Old-Growth Forest Area in the Southern Adirondacks of New York." Bulletin of the Torrey Botanical Club, 121(1): 76–83.

Observations of Lonicera × bella complex at the SCA

edit

The following photographs and corresponding iNaturalist observations of Lonicera were made at or very near the Skaneateles Conservation Area. Click on images to enlarge and read details on Wikimedia Commons or on the "iNat obs" links to view the corresponding observations at iNaturalist.