A06_Attchmt17_InvasivePlantSpecies_WatchList.pdf

Integrated Invasive Plant Management for the Medford District Revised Environmental Assessment

Chapter 2 – Integrated Invasive Plant Management and the Alternatives

Recreation sites, both developed and dispersed, are the hub of several means of invasive plant spread. Recreation sites bring together people and their recreation equipment, vehicles, pack stock and pets where roads, trails, and waterways converge. Invasive plants can be easily transported from one site to other areas on the District and beyond. (See Map 2-2A, Routes of Invasive Plant Spread: Recreation Sites and Waterways.)

Timber harvest, restoration, prescribed fire, and silviculture activities disturb vegetation and soil in ways that can stimulate existing invasive plant seed banks, reduce barriers to invasive seed dispersal, and improve site conditions for invasive plant establishment and growth. Particularly where project disturbances are more severe, such as skid roads and burn pile scars, invasive plant infestations can persist and become sources for further seed spread.

Equipment and work crews can also spread invasive plant seeds to and from project areas.

Mineral material sites such as quarries and mining operation sites are continuously disturbed and may have numerous users. Vegetation and top soil are removed during mining activities, and revegetation efforts may need several successional phases in order to reclaim the site. During these phases, the site may be vulnerable to establishment by invasive plants. (See Map 2-2D, Routes of Invasive Plant Spread: Material Sites and Mineral Resources.)

Wildfires create disturbances and remove shade and native vegetation, creating opportunities for invasive plants to establish before native vegetation has a chance to regrow. High intensity wildfire can destroy organic soil horizons that are conducive to native plant establishment and propagation. Without these substrates, invasive plants can gain a foothold. Invasive plants may also increase hazardous fuels in ways that increase fire intensity or frequency in ecosystems (Brooks et al. 2004).

Category IV: New Invaders

Species of invasive plants not previously documented on the District may be found at any time. Initial infestations are small, but may become large before being discovered. Common routes of spread (e.g., roads and waterways) are checked regularly. Species of concern not yet documented on the District but documented on adjacent lands include perennial pepperweed (Lepidium latifolium), plumeless thistles (Carduus acanthoides, C. crispus, and C.

tenuiflorus), and myrtle spurge (Euphorbia myrsinites) (see Table 2-4, Invasive Plants Documented on Neighboring Lands but Not Known to Occur on the District). For example, perennial pepperweed is present around the shore of Emigrant Lake on adjacent public and private lands, but has yet to be detected on BLM-managed lands. The District works with numerous entities to coordinate early detection activities across jurisdictional boundaries and educate the public about new invasive plants that are invading the area. All new invaders are a high priority for treatment in order to prevent them from becoming established on the District (see further information in the Prioritizing Areas for Treatment section later in this Chapter).

Table 2-4. Invasive Plants Documented on Neighboring Lands but Not Known to Occur on the District

Family Scientific Name Common Name Duration

ODA

Status1 Treatment

Group2

Dicots Apocynaceae (dogbane) Nerium oleander oleander Perennial NL D9 Aquifoliaceae (holly) Ilex aquifolium English holly Perennial NL D12

Asteraceae (aster)

Carduus acanthoides spiny plumeless thistle Biennial A list D4 Carduus crispus curly plumeless thistle Biennial A list D4 Carduus pycnocephalus ssp. cinereus Turkish thistle Annual B list D2 Carduus tenuiflorus winged plumeless thistle Annual B list D2 Centaurea iberica Iberian starthistle Perennial A list D4 Hieracium aurantiacum orange hawkweed Perennial A list D4 Onopordum tauricum bull cottonthistle Biennial A list D4 Tussilago farfara coltsfoot Perennial A list D4

Integrated Invasive Plant Management for the Medford District Revised Environmental Assessment

Chapter 2 – Integrated Invasive Plant Management and the Alternatives

Family Scientific Name Common Name Duration

ODA

Status1 Treatment

Group2

Balsaminaceae (touch-me-not)

Impatiens glandulifera ornamental jewelweed Annual B list D1

Boraginaceae (borage) Anchusa azurea Italian bugloss Perennial NL D5 Echium plantagineum salvation jane Biennial A list D5

Brassicaceae (mustard) Lepidium latifolium perennial pepperweed Perennial B list D6 Lunaria annua annual honesty Biennial NL D6

Buddlejaceae (butterfly bush)

Buddleja davidii orange eye butterflybush Perennial B list D12

Cuscutacea (dodder) Cuscuta spp. dodder Perennial B list D9

Euphorbiaceae (spurge) Euphorbia lathyris caper spurge Annual NL D1 Euphorbia myrsinites myrtle spurge Perennial B list D9

Fabaceae (pea) Galega officinalis goatsrue Perennial A list D7

Lamiaceae (mint) Salvia aethiopis Mediterranean sage Biennial B list D9 Salvia sclarea clary sage Biennial NL D9

Lythraceae (loosestrife) Lythrum hyssopifolium hyssop loosestrife Biennial NL D9 Lythrum tribracteatum threebract loosestrife Biennial NL D9

Malvaceae (mallow) Abutilon theophrasti velvet-leaf Annual B list D1 Menyanthaceae (buckbean)

Nymphoides peltata yellow floatingheart Perennial A list A-ALT

Oleaceae (olive) Ligustrum vulgare European privet Perennial NL D12 Onagraceae (evening primrose)

Ludwigia grandiflora large-flower primrose willow

Perennial B list A-ALT

Orobanchaceae (broomrape)

Orobanche minor clover broomrape Annual B list D1

Polygonaceae (buckwheat)

Polygonum polystachyum cultivated knotweed Perennial B list D11 Polygonum bohemicum Bohemian knotweed Perennial NL D11

Primulaceae (primrose) Lysimachia nummularia creeping Jenny Perennial NL D9 Lysimachia punctata large yellow loosestrife Perennial NL D9 Lysimachia vulgarism garden yellow loosestrife Perennial A list D9

Ranunculaceae (buttercup)

Ficaria verna fig buttercup Perennial NL D9

Rosaceae (rose)

Cotoneaster spp. Cotoneaster Perennial NL D12 Crataegus monogyna et al. hawthorns Perennial NL D12 Prunus avium et al. ornamental cherries Perennial NL D12 Pyracantha coccinea, P. fortuneana firethorns Perennial NL D12 Pyrus calleryana Callery pear Perennial NL D12

Solanaceae (nightshade) Solanum aviculare New Zealand nightshade Perennial NL D9 Solanum rostratum buffalobur Annual B list D2

Tamaricaceae (tamarisk) Tamarix ramosissima saltcedar Perennial B list D12 Monocots

Araceae (arum) Arum italicum Italian lords and ladies Perennial NL M2 Cyperaceae (sedge) Isolepis setacea bristleleaf bulrush Perennial NL A Hydrocharitaceae (frogbit)

Egeria densa South American waterweed

Perennial B list A-ALT

Poaceae (grass)

Arundo donax giant reed Perennial NL M2 Bambusoideae spp. bamboo Perennial NL M2 Cortaderia jubata, C. selloana pampas grasses Perennial B list M2 Nardus stricta matgrass Perennial A list M2 Saccharum ravennae ravennagrass Perennial A list M2 Setaria faberi Japanese bristlegrass Annual NL M1

Pontederiaceae (pickerel-weed)

Eichhornia crassipes water hyacinth Perennial NL M2

1. Noxious weeds are classified by the ODA for the purpose of prioritizing and implementing noxious weed control projects (ODA 2017):