Does Oregon’s climate stop invasive trees?

Low humidity can slow establishment, but many invasives are drought-adapted or tap into irrigation, leaks, washes, and riparian zones. Once established, they can outcompete natives for scarce water and spread rapidly along corridors and disturbed soils.

Where can I report invasive weeds in Oregon?

Use Oregon Department of Agriculture (NDA) resources and their mapping/reporting options (including EDDMapS-based reporting) with clear photos and precise location details.

Is cutting saltcedar or tree-of-heaven enough to control it?

Usually not. Many woody invasives resprout after cutting. Successful control typically requires resprout-aware methods (often cut-stump treatment where appropriate) and follow-up monitoring for multiple seasons.

When is the best time to remove invasive species in Oregon?

Removal is often most effective in spring or fall when soil moisture is higher and plants are actively moving resources, but timing can vary by species and site. Plan for follow-up control to catch resprouts and seedlings.

Virginia Invasive Trees: Chesapeake Bay + I-95 Corridor Guide (Richmond + Northern Virginia)

Virginia spread dynamics: highways, rivers, redevelopment, and the Bay

Invasive trees and plants often establish where soils are disturbed (construction, utility work, new subdivisions) and where corridors concentrate movement. In Virginia, riparian zones and drainage networks connect directly to the Chesapeake Bay watershed, so protecting stream buffers is a high-impact action.

I-95 corridor

Northern Virginia, Fredericksburg, Richmond, and Hampton Roads redevelopment and landscaping create steady seed sources that spread into parks, yards, and farm edges.

I-81 valley routes

Freight movement and disturbed shoulders can transport seed into the Shenandoah Valley and adjacent foothills.

Streams & buffers

Streambanks, ditches, and floodplains move seed and fragments. Early detection along banks prevents large downstream infestations.

Common hotspots include Northern Virginia (Alexandria/Arlington/Fairfax), Richmond, Hampton Roads (Norfolk/Virginia Beach), and inland metros like Roanoke, with spread into smaller towns along corridors.

3 invasive trees to know in Virginia

Each example includes fast ID cues, common Virginia habitats, why it is harmful, and how it spreads.

Tree-of-heaven (Ailanthus altissima)

Where it is from: Asia; widely introduced as an ornamental and now naturalized.

Tree-of-heaven (Ailanthus altissima)

Fast ID: Large compound leaves with many leaflets; clusters of papery winged seeds; crushed leaves can smell rancid.

Common Virginia habitats: Vacant lots, rail edges, interchanges, industrial sites, and disturbed soils from Northern Virginia to Richmond and Hampton Roads.

Why it is harmful: Aggressive root suckering and resprouting; forms dense thickets that crowd out native regeneration.

How it spreads: Wind-dispersed seed plus vigorous vegetative spread from roots, especially after cutting.

Callery pear (Bradford pear) escaping landscaping in Virginia and spreading into field edges

Callery pear (Bradford pear) (Pyrus calleryana)

Where it is from: East Asia; planted widely for spring flowers; now a common escapee.

Callery pear (Bradford pear) (Pyrus calleryana)

Fast ID: Showy white spring flowers; glossy oval leaves; small hard fruits; dense thorny wild forms in old fields.

Common Virginia habitats: Suburban edges, roadsides, powerline corridors, and meadow/woodland edges across the Piedmont and Tidewater.

Why it is harmful: Outcompetes native shrubs and young trees in sunny openings; increases maintenance costs for farms and parks.

How it spreads: Birds disperse fruit; seedlings establish rapidly in disturbed soils and sunny edges.

Princess tree (Paulownia tomentosa) colonizing a disturbed slope in Virginia near the Appalachian foothills

Princess tree (Empress tree) (Paulownia tomentosa)

Where it is from: China; introduced as an ornamental; spreads readily from seed.

Princess tree (Empress tree) (Paulownia tomentosa)

Fast ID: Very large heart-shaped leaves; purple flower clusters in spring; seed capsules persist through winter.

Common Virginia habitats: Disturbed slopes, stream banks, quarries, and rocky soils - common near the Appalachians and redevelopment zones.

Why it is harmful: Fast colonizer of disturbed sites; can dominate openings and reduce native pioneer diversity.

How it spreads: Produces abundant wind-dispersed seed; establishes on bare soil after disturbance.

3 invasive plants to watch in Virginia

These plants commonly spread along trails, streambanks, disturbed lots, and shaded edges across the state.

Japanese stiltgrass forming a dense mat in a Virginia forest edge

Japanese stiltgrass (Microstegium vimineum)

Shade-tolerant annual grass that blankets forest edges and trails, reducing native wildflowers and tree seedlings.

Japanese knotweed along a Virginia streambank with dense bamboo-like stems

Japanese knotweed (Fallopia japonica)

Streambank invader that spreads by rhizomes and fragments. Avoid moving soil from infested sites.

Kudzu vine covering trees and shrubs along a Virginia roadside corridor

Kudzu (Pueraria montana var. lobata)

Fast-growing vine that smothers shrubs and trees; monitor warm slopes, rights-of-way, and old plantings.

For nurseries & landscapers: prevent spread before it starts

Invasives often enter projects unintentionally: legacy ornamentals, volunteer seedlings in containers, contaminated mulch or soil, and moving fill from infested sites. Stocking native alternatives and advising customers about follow-up control reduces long-term maintenance and reinfestation.

Common entry pathways

Volunteer seedlings in pots, contaminated mulch/soil, and moving fill from infested sites are frequent causes of accidental spread.

How to advise customers

Explain that many invasives resprout after cutting, recommend native replacements, and set expectations for monitoring for 2-3 seasons.

What to stock instead

Redbud, serviceberry, river birch, black gum, native oaks, and pollinator shrubs matched to site moisture and space.

What to do once identified

Best results come from confirming ID, containing seed movement, removing invasives safely, disposing properly, and replanting quickly. In Virginia, spring and fall are often the best work windows.

1) Confirm the ID

Photograph leaves, bark, and fruit/flowers. Get local confirmation if unsure before removing large trees.

2) Contain spread

Bag seed or fruit material. Avoid moving soil or brush from infested sites into woods, streams, or parks.

3) Remove + follow up

Seedlings: pull early. Resprouters: do not rely on cutting alone. Return for follow-up for multiple seasons.

4) Protect buffers

Streambanks feeding the Chesapeake Bay watershed are high priority. Replant native buffers to stabilize soils.

5) Dispose correctly

Keep seed-bearing debris contained and follow local guidance; never dump yard waste into waterways.

6) Monitor

Re-check at least 2-3 seasons. Treat resprouts and seedlings early to prevent reinvasion.

What to plant instead in Virginia

Choose natives matched to your site (urban yard, farm edge, or riparian buffer) to stabilize soil and reduce reinvasion.

Eastern redbud (Cercis canadensis)

Great small tree for yards and streetscapes; supports pollinators early in spring.

Serviceberry (Amelanchier spp.)

Multi-season interest; berries for wildlife; strong replacement for invasive ornamentals.

River birch (Betula nigra)

Excellent for wetter sites and stream buffers; helps stabilize banks.

Black gum (Nyssa sylvatica)

Tough native with great fall color; useful for yards and restoration.

White oak (Quercus alba)

Keystone native; excellent long-term canopy choice where space allows.

Buttonbush (Cephalanthus occidentalis)

Pollinator shrub for wet edges; great for riparian buffers.

FAQs: invasive trees and plants in Virginia

Tree-of-heaven, Callery pear (Bradford pear), and princess tree are among the most frequently encountered invasive trees across Virginia's cities, suburbs, and disturbed corridors.

These highways concentrate soil disturbance and vehicle movement that carry seed. Interchanges, construction zones, and roadside edges become invasion launch points into neighborhoods, farms, and parks.

Northern Virginia, Richmond, and Hampton Roads are common hotspots due to redevelopment and landscaping, with spread into the Shenandoah Valley and foothills via corridors and waterways.

Invasives can weaken native riparian buffers and increase management needs along streams that feed the Bay, especially where banks are disturbed.

Usually not. Tree-of-heaven often resprouts and sends up root suckers after cutting. Successful control requires follow-up for multiple seasons.

Spring and fall are usually best because temperatures are moderate and plants are actively moving resources. Follow-up control is essential.

Common pathways include legacy ornamentals, volunteer seedlings in containers, contaminated mulch or soil, and moving fill from infested sites. Native substitution lists and clean stock checks help prevent spread.

Start at edges: fencerows, drainage ditches, hedgerows, and vacant lots. Remove seedlings early, prevent seed spread, and replant with natives to reduce reinfestation.

Photograph and confirm ID, remove small infestations early, bag seed-bearing material, and never dump yard waste in woods or stream corridors.

Choose Virginia natives such as redbud, serviceberry, river birch, black gum, and native oaks matched to your site and soil moisture.

Invasive Trees in Virginia

Softwoods

Hardwoods

Calculators

Resources

Programs

Invasive Trees and Plants in Virginia: What to Spot, What to Remove, and What to Plant Instead

Virginia spread dynamics: highways, rivers, redevelopment, and the Bay

I-95 corridor

I-81 valley routes

Streams & buffers

3 invasive trees to know in Virginia

Tree-of-heaven (Ailanthus altissima)

Tree-of-heaven (Ailanthus altissima)

Callery pear (Bradford pear) (Pyrus calleryana)

Callery pear (Bradford pear) (Pyrus calleryana)

Princess tree (Empress tree) (Paulownia tomentosa)

Princess tree (Empress tree) (Paulownia tomentosa)

3 invasive plants to watch in Virginia

Japanese stiltgrass (Microstegium vimineum)

Japanese knotweed (Fallopia japonica)

Kudzu (Pueraria montana var. lobata)

For nurseries & landscapers: prevent spread before it starts

Common entry pathways

How to advise customers

What to stock instead

What to do once identified

1) Confirm the ID

2) Contain spread

3) Remove + follow up

4) Protect buffers

5) Dispose correctly

6) Monitor

What to plant instead in Virginia

Eastern redbud (Cercis canadensis)

Serviceberry (Amelanchier spp.)

River birch (Betula nigra)

Black gum (Nyssa sylvatica)

White oak (Quercus alba)

Buttonbush (Cephalanthus occidentalis)

FAQs: invasive trees and plants in Virginia

What are the most common invasive trees in Virginia?

Why do I-95, I-81, and I-64 matter for invasive spread in Virginia?

Which Virginia areas report invasive trees most often?

How do invasives affect the Chesapeake Bay watershed?

Is cutting tree-of-heaven enough to control it?

When is the best time to remove invasive trees and plants in Virginia?

How do invasives enter the landscape trade in Virginia?

What should farms and yards along corridors do first?

What can I do immediately if I find an invasive in my yard?

What should I plant instead of invasive ornamentals in Virginia?

Tree Plantation

Explore

Head Office

Field Office