Attack of the Aliens (Radell)

How to Identify

& Control Invasive Plants

Marc Radell

Master Gardener Volunteer

PennState Extension of Montgomery County

www.marcmradell.com

ª Role of Plants in Ecosystem

ª What Makes a Plant “Invasive”

ª General Control Strategies

ª Chemistry of Soils

ª Adapted to Climate

ª Relation with Soil Organisms

ª Herbivory by Insects

ª Nutritional Value for Wildlife

ª Biodiversity

ª Not native to the region

ª Opportunistic, move into disturbed areas

ª Spread quickly and aggressively

• Often reproduce by shoots or roots

• Or lots and lots of seeds

ª Not kept in check naturally

• Diseases/pests not present

• Benefit from human alteration of

environment

ª Displace other plants in natural areas

• Form monocultures

ª Displace native plants,

sustaining 50-70% fewer insects

ª Contributed to decline of 42% of U.S. endangered and threatened species (18% main cause)

ª More than $97 billion spent annually controlling 79 species

ª Reduce habitat value and nesting sites

ª Interfere with succession

from field to forest

ª Can alter nutrient cycling &

local hydrology

ª Significantly

alter ecosystem in natural areas

ª Deer prefer native species

ª Invasive plants are

disproportionately resistant

ª Deer actively spread some

invasive seeds

ª Healthy: < 15/square mile

ª WMU 5C: 38/square mile

ª Pointless to manage invasive plants without managing deer

ª Some native plants also

spread aggressively

ª Usually kept in check in

natural environment

ª Become nuisances in disturbed areas

ª Still provide ecosystem

benefits when controlled

ª Make more “growing space”

available to natives, less to invasives

ª Focus on keeping good areas good

ª Focus on layer than controls most growing space

ª Replant right away

ª Agent

ª Discriminatory

ª Toxicity

ª Persistence

ª Minimize new disturbance

ª Use fertilizers wisely

ª Develop a maintenance plan

ª Monitor conditions

ª Remove new invasives ASAP

ª Replace them immediately

ª Recreate Penns Woods

ª Reduce Edge Habitat

ª Plant Densely

ª Mulch disturbed areas

ª Physically remove plants and destroy reproductive parts

ª Or cut them to ground (starve them)

ª Fire/Torch

ª Girdle

ª Solarize

ª Mow

ª Plant populations are controlled by a complex of multiple species

ª Biological agent may require

other environmental factors

ª Seldom effective alone

ª Danger of host-shifting

ª Generally not practical for home owners

ª Goats? Rose rosette?

ª Can be effective part of

overall strategy

ª Can migrate via root grafts

ª Apply only to target species

ª Apply at correct time in growth cycle

ª Cut plant back and apply herbicide to stump (for Fall) or resprouted vegetation

ª Apply only as directed

ª Most effective against annuals as part of greater strategy

ª “Safer” Foliar Sprays • Horticultural Soap • Dormant oil

ª Acidic Foliar Sprays • Vinegar

• Citric Acid

ª Means of last resort

ª Application

• Foliar • Basal bark • Hack & squirt • Injection • Cut stump

ª Apply only as directed

Herbicide Brand_ExamplesName TargetWeedSpecies Average_Half Soil -life Mobility

2,4 D Navigate

®_{, Class}®_,

Weed-Pro®, Justice® _{broadleaf weeds 10 days moderate-high}

Clopyralid Reclaim

®_{, Curtail®,}

Transline® broadleaf weeds 40 days moderate-high

Fluazifop-p-Butyl Fusilade DX®, Fusion®, Tornado® _{grasses 15 days moderate*}

Fosamine Krenite® _{trees and bushes 8 days moderate*}

Glyphosate RoundUp

®_{, Rodeo}®_,

Accord® all weeds 47 days low

Hexazinone Velpar®_{, Pronone}® _{all weeds 90 days moderate-high}

Imazapic Plateau

®_{, Plateau}

Eco-Pak®, Cadre® _{all weeds 120-140 days low?}

Imazapyr Arsenal® _{grasses, broadleafs, vines, brush, and trees 25-141 days low-moderate}

Picloram TordonK® _{broadleaf weeds, vines, and woody plants 90 days moderate-high}

Sethoxydim Poast® _{annual and perennial grasses 5 days high*}

Triclopyr Garlon®_{, Remedy}® _{woody and annual broadleaf weeds 30 days moderate-high}

ª Amur Maple

ª Norway Maple

ª Tree-of-Heaven

ª Mimosa

ª White Mulberry

ª Princess Tree

ª Callery Pear

ª Pull, torch or spray seedlings

ª Mow or graze meadows

ª Grub out individual plants

ª Girdle in Spring

ª Cut and treat stump with glyphosate or triclopyr

ª “Hack & squirt” trunk with glyphosate, triclopyr or imazapyr

ª Treat basal bark with triclopyr

ª Barberry

ª Butterfly Bush

ª Russian Olive

ª Autumn Olive

ª Burning Bush

ª Privet

ª Shrub Honeysuckles

ª Japanese Spiraea

ª Multiflora Rose

ª Wineberry

ª Allegheny Blackberry

ª Reduce edge habitat

ª Pull, torch or spray seedlings

ª Mow or graze meadows

ª Grub out individual plants

ª Repeat cutting

ª Foliar spray of fosamine

ª Cut and treat stump with

glyphosate or triclopyr

ª Treat basal bark with triclopyr

ª Asian Wisterias

ª Japanese Honeysuckle

ª English Ivy

ª Vinca

ª Wild Grape

ª Virginia Creeper

ª Poison Ivy

ª Trumpet Vine

ª Reduce edge habitat

ª Pull up vines and roots

ª Cut climbers at ground and again high as you can reach

ª Smother or solarize ground vines

ª Apply glyphosate or triclopyr to stumps

ª Treat basal bark with triclopyr

ª Japanese Stiltgrass

ª Garlic Mustard

ª Don’t till

ª Apply mulch

ª Pull up or mow

ª Use preemergents

ª Torch or burn plants

ª Don’t let them seed!

ª Use targeted herbicides

ª Canada Thistle

ª Star of Bethlehem

ª Lesser Celandine

ª Bristled Knotweed

ª Pokeweed

ª Pigweed

ª Ragweed

ª Don’t till

ª Establish dense native plant communities

ª Pull up or mow

(repeatedly)

ª Destroy reproductive

parts

ª Torch or burn plants

ª Use targeted herbicides

ª Develop a management strategy ª Establish dense, native plant

communities

ª Focus on maintaining healthy areas ª Monitor for/remove new invasives ASAP ª Control deer

ª Physically remove invasives when possible

ª Destroy reproductive parts ª Torch or smother when possible