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Excerpts from recent issues of Invasive Plant Newsletter
These news items pertain to events in New Hampshire, Vermont or in the Upper Valley region. These articles have been organized by topic [and date], and are culled from an irregular newsletter published by the Upper Valley Purple Loosestrife Coalition.
Proposed Rule Making on Noxious Weeds in VT: A Complex Process
Scott Pfister Phone: (802) 828-3481
The following criteria were developed with assistance of the ad-hoc VT Invasive Exotic Plant Committee:
upland plants: goutweed, tree-of-heaven, garlic mustard, oriental bittersweet, Japanese knotweed, common buckthorn, glossy (European) buckthorn, Bell's honeysuckle, Japanese honeysuckle, Amur honeysuckle, Morrow's honeysuckle, Tartarian honeysuckle, black swallowwort and pale swallow wort.
aquatic plants: yellow flag iris, common reed (Phragmites) , purple loosestrife, flowering rush, frogbit, hydrilla, E.Indian hygrophila, fanwort, Brazilian elodea, parrot feather, variable- leaved milfoil, Eurasian watermilfoil, yellow floating heart, curly leaf pondweed, four types of salvinias and water chestnut.
This list is similar to one in circulation, entitled Vermont Invasive Exotic Plant Fact Sheet Series, dating from Spring, 1998. It has additions to the old list of the salvinias and the swallow-worts; and the notable omissions of Japanese barberry, European barberry, Norway maple, Russian and Autumn Olives -- which were on the original list.
Scott Pfister notes that the quarantine process has many steps: Currently,
he is seeking input on the criteria that were used to list plants and if
the proposed plants meet the criteria. Once comment has been received,
he will draft the proposed rule and submit it to the Interagency Committee
on Administrative Rules (ICAR). This is the start of the formal rule making
process. If accepted by ICAR, the proposed rule will go out for public
comment and public hearings will be held. The department will then need
to respond to all public comment and amend the rule as appropriate reflecting
the public comment. The rule then goes to the Legislative Committee on
Administrative Rules (LCAR). This committee consists of legislators that
review the public comment and vote as to whether the rule meets the intent
of the law that authorizes the rule. [1/01]
NH Invasive Species Committee Working on a Draft List
Control Agent for Multiflora Rose, Slowly Advancing Eastward
Norway Maple, an Effective Invader of Undisturbed Forest
Understory stem densities provide another picture, however: Norway maple seedlings out compete other shade tolerant species: Norway maple understory had low diversity and a preponderance of Norway maple seedlings. Sugar maple and beech had significantly higher diversity in the understory, but Norway maple seedlings still accounted for 81% of all woody seedlings beneath sugar maples and 80% of seedlings beneath beech trees. The tree does not require the forest edge to initiate invasion, although recruitment from adjacent landscape plantings does accelerate its progress. The article concludes that the plant is clearly a threat to forest diversity, and to the preservation of native wildflowers and shrubs, which the tree out-competes.
A "wild" section of Central Park (The North Woods) had suffered the
same experience as the Drew Forest; a concerted effort to remove Norway
maple trees and seedlings has resulted in a surprising recolonization by
native species. A similar observation of Norway maple dominance in understory
is reported in recent (winter 2000-2001) edition of The Land Steward, a
newsletter of the Finger Lakes Land Trust. In an informal survey of tree
species in Fall Creek gorge in Ithaca NY, 60 specimens of 12 native trees
were found; but three invaders were represented in amazing numbers ---
50 seedling ailanthus, 238 Norway maples, two dozen glossy buckthorns.
The solution to this problem is certainly tough -- remove those trees present
and prevent future invasions. [2/01]
Towards A Native-Grass Seed Mix for New England
Currently, native grass seed supplies often come from the mid-west or other areas, where the seed may be genetically different than the native grasses found here in the North East. Of our native species, the only commercially available cultivars from the Northeast are 'Niagara' big bluestem and 'Tioga' deertongue, two warm season grasses. There are no selected and tested cultivars currently available of our native cool season grasses.
To remedy this problem, the Plant Materials Program of the NRCS* has collected specimens of 10 native cool season grasses (collected from 178 sites), and 8 warm season grasses (with samples collected from 90 sites). The cool season species to be investigated include: Poverty oatgrass, Canada bluejoint, Bottlebrush, Canadian wildrye, Virginia wildrye, Riverbank wildrye, Hairy wildrye, Drooping woodreed, Stout woodreed, and Crinkled hairgrass. Seed was collected from sites within New England, NY and PA.
These 268 seed samples will be evaluated at the NRCS Plant Materials Center in Corning, NY. The selected collections then will be tested at several sites within the region, and assessed for qualities such as root structure, plant survival, growth response, phenology, and biomass. Depending on the results of this assessment, final selection will be made for release to commercial production, to form the basis of regional native seed mixes for use in many conservation and farm plantings such as permanent wildlife cover, disturbed lands reclamation, forage, and possibly biofuel cropland. The project is expected to take from 5 to ten years until completion, with successful species made available during that time frame.
In addition, the agency is currently developing selections of these warm-season grasses: switchgrass, indiangrass, prairie cordgrass, big bluestem, little bluestem, seaside bluestem, broomesedge, and deertongue.
* Natural Resources Conservation Service -- formerly the Soil Conservation
Service, a branch of the USDA, with offices in most counties.
Montshire Native Grass Experiment -- a Great Success, to be Extended
Garlic Mustard Making Inroads -- Plainfield, Hanover, Thetford and
At the New England Wildflower Society's sanctuary on River Rd in Plainfield NH, Chris Mattrick, rare plant curator and invasive plant lead attacker for the NEWFS, reports that volunteers collected 37 50-gallon bags of garlic mustard over a two day period at the end of May, just when the plant was beginning to set seed. The group worked on a larger area than last year, but only collected 2 more bags this year than last. He's not sure what this means - but feels that the quantity was no worse this year than last. When Chris came to NEWFS in 1995 and visited the sanctuary then, he did not note Alliaria in the species list. He first noted the plant in 1997 and by 1998 it was a big problem and spreading. The first control effort was 1999, so now we have the data from 1999 and 2000. Other problem species of note at the site - both Celandine (Chelidonium majus ) and Aegepodium (Bishop's weed or goutweed) are definitely on the increase in the area, especially on the river side of the road.
Garlic Mustard has also been found next to a construction site on Buck Rd in Hanover, and seems to be associated with hay bales used to retain runoff silt -- probably a gift from the place which grew the hay. Weed-free hay (straw) is much more expensive. This suggests yet another requirement for construction sites and their enforcement. There has been an honest effort to pull all the garlic mustard plants in the Buck Road area, but the site will have to be monitored for several years to be certain it has been contained. Apparently the plant has also appeared in Thetford, near Geary Road. The NH Nature Conservancy sent out a crew to tackle the plant on Hart Island in Hartland where it has recently appeared (along with the Black Swallow-wort which is a perennial problem in the area). [6/00]
A Market for Japanese Knotweed Revealed by CA Floral Designer
Canaan: Dave Barney, who has been concerned with monitoring water
quality at Goose Pond, reports finding a total of five scattered small
stands of purple loosestrife near the pond or Little Goose Pond and one
in a garden on Goose Pond Rd. All have been removed, neighbors of those
plants have been informed, and our color brochure will be distributed in
a spring mailing. These measures are very important, for when there are
just a few plants it is possible to stop a loosestrife invasion (the plant
has three morphs, and to produce viable seeds, each plant must be crossed
with one of the other two types) [11/00]
Lebanon: When the city's Site Plan Regulations were revised about four years ago (in 1996), one provision was introduced to help slow the introduction of invasive plants. The City of Lebanon now requires that invasive plants cannot be used to satisfy landscaping requirements. The list of exotic invasive plants includes the following 22 species (several of these are no longer sold at nurseries, but many are still for sale): Acer plantanoides (Norway maple ) ; Aedopodium podagraria (Bishopsweed or goutweed ) ; Ailanthus altissima (Tree-of-heaven); Ampelopsis brevipedunculata (Porcelain berry); Berberis thunbergii (Japanese barberry); Berberis vulgaris (European or common barberry); Celastrus orbiculatus (Asian Bittersweet); Coronilla varia (Crown vetch); Cytisus scoparius (Scotch broom); Elaeagnus angustifolia (Russian olive); Elaeagnus umbellata (Autumn olive); Euonymus alata (Burning bush) ; Euonymus fortunei (Climbing euonymus, wintercreeper); Hedera helix (English ivy); Lonicera japonica (Japanese honeysuckle); Lonicera maackii (Amur honeysuckle); Lonicera morrowii (Morrow's honeysuckle); Lythrum salicaria (Purple loosestrife); Phragmites (Common reed); Rhamnus cathartica (Common buckthorn, tallhedge); Rhamnus frangula (European buckthorn, Glossy buckthorn); Rosa multiflora (Multiflora rose, baby rose) [4/00]News About Control of Purple Loosestrife
Purple Loosestrife Collapse at Several Bio-control Sites
At most of these sites, the beetles were released four years ago. The term "collapse" doesn't mean that purple loosestrife is eradicated at these sites. It does mean that the leaf-eating beetles (Galerucella pusilla or G. calmariensis ) have reached sufficient numbers and that the plant is being suppressed by the beetles. The plants are weakened, but some will survive. The beetles should remain a presence, to help keep loosestrife numbers in check in the future. [11/00]
Bio-Control Programs in NH and VT -- Area Activities in summer 2000
In NH, beetles were released at five sites in the Upper Valley: Reed's Marsh WMA in Orford (near boat launch), Wilder WMA in Lyme, Wilson's Landing boat launch in Hanover and on private property in Enfield (Mascoma Lake) and in Lyme. In the case of Wilson's Landing, both the Hanover Conservation Commission and Select Board gave approval for the beetle release; and neighbors submitted a letter of support for the bio-control initiative. At each of these NH sites, there is an individual responsible for monitoring the site for the next three years, who will share data with the state, the landowner and the local conservation commission. Both states are planning to have citizens rear and release beetles next summer. [11/00]