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Prevention and Early Detection

Introduction to Prevention and Early Detection

The most effective, economical, and ecologically sound approach to managing invasive plants is to prevent their invasion in the first place. Often landowners and land managers direct limited resources to fighting firmly established infestations. By that stage, management is expensive and eradication is probably impossible. Certainly it is necessary to manage infestations to limit the spread of invasive plants into non-infested areas. However, limited resources might be spent more efficiently on proactive weed management that controls existing weed infestations but also focuses strongly on prevention or early detection of new invasions.

Prevention and Early Detection in theory, are Management Tools. These concepts are presented in a seperate section the hopes that they remain important consideration throughout the Adaptive Management process.

Prevention

Elements of a proactive weed prevention plan include:

• Limiting the introduction of weed seeds into an area;
• early detection and eradication of small patches of weeds;
• minimizing disturbance of desirable vegetation along roadsides, trails, and waterways;
• managing land to build and maintain healthy communities of native and desirable plants to compete with weeds;
• careful monitoring of high-risk areas such as human and animal transportation corridors and disturbed or bare ground;
• revegetating disturbed sites with desirable plants; and
• evaluating annually the effectiveness of the prevention plan so appropriate adaptations can be implemented the following year.

The purpose of this guide is to provide practical techniques to prevent the invasion and permanent establishment of invasive plants on roadsides and in natural areas. It is divided into four sections:

• Invasive Plant Prevention = Lands addresses prevention strategies for site-disturbing projects such as road-building and timber harvesting, considerations for land-use planning, and movement of people and equipment within natural areas.
• Invasion Plant Prevention = Water addresses prevention strategies in riparian areas and watersheds, as well as providing tips for aquatic recreation.
• Invasive Plant Prevention = Animals addresses prevention strategies specific to grazing management, wildlife, and movement of horses and pack animals into the backcountry.
• Invasive Plant Prevention = Fire addresses prevention strategies for prescribed burns as well as firefighting and post-fire land rehabilitation.

Another word for "prevention" is "protection." This guide was developed with the firm conviction that we can protect our healthy, non-infested ecosystems from the introduction and establishment of invasive plants by following practical, proactive, weed prevention guidelines.

Invasive Plant Prevention: Lands

Site-Disturbing Projects and Maintenance Programs

When planning projects that will disturb grasses, forbs, and shrubs and result in bare ground -even temporarily - land managers must incorporate weed prevention and control into project layout, design, and evaluation, as well as all project decisions. Consider how to rebuild or maintain healthy plant communities that will effectively compete with weeds after the disturbance.

• Environmental analyses for projects and maintenance programs should assess weed risks, analyze high-risk sites for potential weed establishment and spread, and identify prevention practices. Determine weed prevention and management needs at the onset of project planning.
• Include site-specific vegetation monitoring in project plans.
• Learn to recognize desirable plants as well as weeds.

Avoid or remove sources of weed seed and other propagules to prevent new weed infestations and the spread of existing weeds.

• Before ground-disturbing activities begin, inventory and prioritize weed infestations for treatment in the project operating areas and along access routes. Identify what weeds are on site or within the project's vicinity and do a risk assessment accordingly. Control these weed infestations. Ideally, weeds should be managed three to five years prior to the planned disturbance to minimize weed seeds in the soil.
• Begin project operations in non-infested areas. Restrict movement of equipment or machinery from weed-contaminated areas to non-contaminated areas. This restriction includes machinery used for or by construction, recreation, agriculture, forestry, oil and gas exploration and production, utility companies, mining, and tourism.
• Locate and use weed-free project staging areas. Avoid or minimize travel through weed infested areas, or restrict travel to those periods when spread of seed or propagules is least likely, such as prior to seed development.
• Identify sites where equipment can be cleaned. Remove mud, dirt, and plant parts from project equipment (preferably with a 2,000-PSI pressure washer) before moving it into a project area. Seeds and plant parts should be collected and incinerated. The cleaning area should be monitored for weeds for several years following.
• Clean all equipment before leaving the project site if operating in areas infested with weeds.
• Inspect, remove, and properly dispose of weed seed and plant parts found on clothing and equipment. Proper disposal means bagging the seeds and plant parts and incinerating them.
• Evaluate options to regulate the flow of traffic on sites where desired vegetation needs to be established or maintained.

Prevent the introduction and spread of weeds caused by infested sand, gravel, and fill material. Work with the responsible transportation agencies to voluntarily adopt prevention practices.

• Inspect materials at the source to ensure that they are weed-free before transport and use. If sources of sand, gravel, and fill are infested, eradicate the weeds, then strip and stockpile the contaminated material for several years, if possible, to further deplete the soil seed bank. Check regularly for weed re-emergence.
• When material from a weed-infested but herbicide-treated source is used in a project, inspect and document the project area annually for at least three years to ensure that any transported weeds are promptly detected and controlled.
• Maintain stockpiled, non-infested material in a weed-free condition by preventing weed seed contamination with physical barriers and by frequently monitoring and quickly eradicating new weeds prior to seed production.

Avoid creating environmental conditions that promote weed germination and establishment.

• Minimize soil disturbance.
• When working in vegetation types with relatively closed canopies, retain shade to the extent possible to suppress weeds and prevent their establishment and growth.
• Retain native vegetation in and around the project activity as much as possible.

Where project disturbance creates bare ground, re-establish vegetation to prevent conditions that favor weeds.

• Revegetate disturbed soil to optimize establishment of desirable plants for that specific site. Define for each project what constitutes disturbed soil and objectives for revegetation.
• Revegetation may include topsoil replacement, planting, seeding, fertilization, liming, and weed-free mulching. Use native material where appropriate and feasible. Consider hiring a contractor to chip local brush or cut and bale local weed-free grass for mulch - an added benefit is that mature seeds in the grass or brush can help restore localized vegetation on the site. Use certified weed-free hay or straw.
• Monitor sites where seed, hay, straw, or mulch has been applied. Eradicate weeds before they develop seed. In contracted projects, contract specifications can require that the contractor maintain the site weed-free for a specified time. Ensure contractors do not skip weed control steps to save time on a project.
• Where practical, salvage weed-seed-free topsoil and replace it on disturbed areas such As road embankments or landings. Healthy topsoil contains microorganisms, invertebrates, and living plant propagules that enhance revegetation.
• · Use local seeding guidelines to determine procedures and appropriate seed mixes. A certified seed laboratory should test each lot according to Association of Seed Technologists and Analysts (AOSTA) standards (which include an all-state noxious weed list) and provide documentation of the seed inspection test. Check state and federal lists to see if any local weeds need to be added prior to testing. If AOSTA standards are not required, use state- or regionally-certified weed-free seed.
• Inspect and document all ground-disturbing operations in noxious weed infested areas for at least three growing seasons following completion of the project. For ongoing projects, continue to monitor until reasonably certain that weeds will not reappear. Plan for follow-up treatments based on inspection results.

Improve effectiveness of prevention practices through weed awareness and education.

• Educate people in weed identification, biology, impacts, and effective prevention measures.
• Provide proficient weed management expertise at each administrative unit of a public land management agency. Expertise means that necessary skills are available and corporate knowledge of ongoing weed management strategies is maintained.
• Develop incentive programs encouraging weed awareness, detection, reporting, and identifying new weed invaders.

Set the example; maintain weed-free administrative sites (sites where administrative buildings, equipment buildings and staff are located).

• Treat weeds at administrative sites and implement weed prevention practices to maintain sites in a weed-free condition. This includes early detection and rapid response practices.

Timber Harvest

Avoid or remove sources of weed seed and propagules to prevent new weed infestations and the spread of existing weeds.

• Treat weeds on timber-harvest projects - including landings, skid trails, and helibases - well before activities commence. Identify and avoid infested areas where activities could spread weed seed.
• Maintain weed-free mill yards, equipment parking, staging areas, and logging roads.
• To prevent weed germination and establishment, retain native vegetation in and around timber harvests and minimize soil disturbance. Logging practices that reduce soil disturbance include:
  • Over-snow logging
  • Skyline or helicopter logging
  • Reuse of landings, skid trails, and helibases when they are weed-free
• Minimize the period from end of logging to site preparation, revegetation, and contract closure. Prompt reforestation and revegetation is required for long-term restoration and weed suppression.
• Monitor for and eradicate new weeds promptly.

Land Acquisition and Subdivisions

Avoid or remove sources of weed seed and propagules to prevent new weed infestations and the spread of existing weeds. Monitor for and eradicate new weeds promptly.

• Conduct weed inventories of all lands considered for acquisition, sale, or exchange. Weed treatment may be written into a contract as a condition of land purchase or exchange. Long-term weed management may be considered in the maintenance cost of the property.
• Public land managers may include a weed prevention and control provision in new permits, easements, or leases. Consider amending existing authorizations when ground disturbing activities are involved.

Incorporate weed prevention into project layout, design, evaluation, and decisions for mining, oil and gas exploration, and utility work.

• Include weed prevention measures, including project inspection and documentation, in operation and rehabilitation plans.
• To prevent conditions favoring weed establishment, minimize bare soil conditions and Reestablish vegetation as soon as possible on disturbed or bare ground.

Incorporate weed management and prevention practices in land subdivision planning.

• Encourage the landowners' association to prevent weed problems through education and awareness. Ensure that property owners understand the impacts caused by weeds, including effects on property values.
• Develop weed management guidelines or a weed prevention plan for the entire subdivision rather than individual lots.
• Include building contractors, utilities, and others in requirements to clean equipment and use weed-free materials.
• Communicate and coordinate with the local county weed district or weed management area.
• Develop standards for grazing, landscaping, and revegetation that promote healthy plant communities.
• Develop road maintenance plans that address weed management along roadsides to reduce the spread of weeds throughout the subdivision.

Recreation and Wilderness

To prevent new weed infestations and the spread of existing weeds, avoid or remove sources of weed seed and propagules.

• Avoid moving through weed infestations whenever possible.
• Inspect and clean motorized and mechanized trail vehicles of weeds and their seeds at a controlled site.
• Wash boots before hiking into a new area. Inspect and clean packs, equipment, bike tires.
• Keep dogs and other pets free of weed seeds. Weeds often grow along trails; leash dogs when weeds are in seed.
• Avoid picking unidentified "wildflowers" and discarding them along trails or roadways.
• Support the development and distribution of weed-free feed, hay, straw, and mulch.
• Maintain trailheads, boat launches, outfitter and public camps, picnic areas, airstrips, roads leading to trailheads, and other areas of concentrated public use in a weed-free condition. Consider high-use recreation areas as high priorities for weed eradication.
• In areas susceptible to weed infestation, limit vehicles to designated, maintained travel routes. Inspect and document travel corridors for weeds and treat well before seed production.
• Monitor for and eradicate new weeds promptly.

Improve effectiveness of prevention practices through weed awareness and education.

• To be most effective, unify landowners in implementing proactive weed management as a cooperative group to maintain common weed-free areas.
• Post weed awareness messages and prevention practices at strategic locations such as trailheads, roads, boat launches, information kiosks, and forest portals.
• Recreation permits and hunting and fishing licenses should include weed prevention guidelines and/or information on weeds that hunters and fishermen are likely to encounter.
• Weed prevention messages should include information about where to report sightings of weeds.

Roads and Utilities

Incorporate weed prevention into road and utility project layout, design, evaluation, and decisions.

• Develop Best Management Practices for road construction material sites, sand and Gravel pits, mulch, and other material source sites.
• Clean all equipment before leaving the project site when operating in areas infested with weeds. Seeds and plant parts should be collected and incinerated. Designate a site where equipment will be cleaned and frequently monitor the site for new weeds.
• Remove mud, dirt, and plant parts from project equipment before moving it into a project area. Seeds and plant parts should be collected and incinerated.
• Communicate with the local weed district or weed management area about projects and best practices for prevention and develop cooperative strategies.
• To avoid weed invasion, build and maintain self-sustaining, healthy plant communities whenever possible, including utility rights of way, roadsides, highway landscaping projects, rest area construction, scenic overlooks, and state entrances.

Remove roadside sources of weed seed that could be transported to other areas.

• Periodically inspect roads and rights-of-way for noxious weeds. Train road maintenance staff and utility truck operators to recognize weeds and report locations to the local weed specialist. Inventory weed infestations and schedule them for treatment.
• Schedule roadside mowing so weed-free roadsides are mowed after seed maturation, ensuring desirable plants grow unrestricted and produce seed for next year's stand. Weedy roadsides should be treated when the weeds have reached the early flowering stage (well before seed development) to avoid spreading matured weed seed.
• Coordinate blading or pulling of noxious weed-infested roadsides or ditches in consultation with the local weed specialist. Blade from least infested to most infested areas. Ensure weeds remain on-site.
• Avoid acquiring water for road dust abatement where access to the water is through weed-infested sites.
• Treat weeds in road decommissioning and reclamation projects before roads are made impassable. Sites with moderate to high weed density should be treated for several seasons prior to decommissioning. Regardless of weed density, revegetation speeds recovery and mitigates soil erosion, as well as prevents weed invasion. Reinspect and follow up based on initial inspection and documentation.

Invasive Plant Prevention: Water

Aquatic Recreation

To prevent new weed infestations and the spread of existing weeds, avoid or remove sources of weed seed and propagules from recreation equipment. Avoid moving weeds from one body of water to another.

• Inspect boats (including air boats), trailers, and other boating equipment and remove any visible plants, animals, or mud before leaving any waters or boat-launching facilities. Drain water from motor, live well, bilge, and transom wells while on land before leaving the vicinity. Wash and dry boats, tackle, downriggers, anchors, nets, floors of boats, props, axles, trailers, and other boating equipment to kill weeds not visible at the boat launch.
• Encourage boat-launching facilities to provide proper washing equipment and kiosks that describe proper and thorough cleaning.
• Before transporting to new waters, rinse boat and boating equipment with hot (40°C or 104°F) clean water, clean boat or trailer with a pressure washer, or dry boat and equipment for at least five days.
• Inspect seaplanes and remove weeds from floats, wires, cables, water rudders, and Pump floats; wash with hot water or spray with high-pressure water, or dry for at least five days.
• Avoid taxiing seaplanes through heavy surface growths of weeds before takeoff; raise and lower water rudders several times to clear off plants. If weeds were picked up during landing, clean off the water rudders before take-off and leave the water rudders up during take-off. If water rudders were down during take-off, raise and lower water rudders several times to free weed plant fragments while over original body of water or over land. If weeds remain visible on floats or water rudders, the pilot may return to flight origin and remove plants if an extra landing and takeoff is not a safety concern.
• Maintain a l00-foot weed-free clearance around boat launches and docks
• Promptly post sites if aquatic invasive weeds are found. Confine an infestation; where prevention is infeasible or ineffective, close the facility until the infestation is contained.
• Wash and dry fishing tackle, downriggers, float tubes, waders, and other equipment to remove or kill harmful species not visible at the boat launch.
• Avoid running personal watercraft through aquatic plants near boat access locations. Instead, push or winch watercraft onto the trailer without running the engine. After the watercraft is out of the water, start the engine for 5 to 10 seconds to blow out any excess water and vegetation. After engine has stopped, pull weeds out of the steering nozzle. Inspect trailer and any other sporting equipment for weed fragments and remove them before leaving the access area. Wash or dry watercraft before transporting to another body of water.
• Waterfowl hunters may use elliptical, bulb-shaped, or strap anchors on decoys because these types of anchors avoid collecting submersed and floating aquatic plants. Remove aquatic plants and rinse mud from waders and hip boots before leaving the water. Remove aquatic plants, animals, and mud attached to decoy lines and anchors.
• Divers should clean their equipment after each use. Be especially careful to wash the buoyancy control device and other items that retain water. All gear should be rinsed with water heated to at least 140° F and everything should be allowed to dry completely between dives.
• Construct new boat launches and ramps at deep-water sites. Restrict motorized boats in lakes near areas that are infested with weeds. Move sediment to upland or quarantine areas when cleaning around culverts, canals, or irrigation sites. Clean equipment before moving to new sites. Inspect and clean equipment before moving from one project area to another.
• Drain the water in bait buckets, live wells, and transom wells on land or back into the water from which it was taken.
• Avoid dumping aquarium water or aquatic plants into local waters. Many plants for water gardens and aquaria are highly invasive.

Watershed Management

Avoid or remove sources of weed seed and propagules to mitigate new weed infestations and the spread of existing weeds.

• Frequently and systematically inspect and document riparian areas and wetlands for noxious weed establishment and spread. Eradicate new infestations before they become established - effective tools for riparian-area management are limited.
• When possible, maintain conditions (for example, water levels) that sustain desired riparian plant systems that compete effectively with weeds.
• Promote dense growth of desirable vegetation in riparian areas to minimize the availability of landing and germination sites for weed seeds and propagules that might be produced upstream.
• Address noxious weed risks in watershed restoration projects and water quality management plans.
• Pay particular attention to practices listed under "Site-disturbing Projects and Maintenance Programs" in this document.

Invasive Plant Prevention: Animals

Grazing Management

Incorporate noxious weed prevention and control practices in the management of grazing allotments. Promote grazing practices that minimize impacts on desirable vegetation.

• Consider prevention practices and cooperative management of weeds in grazing allotments. Proper grazing management and prevention practices may include:
  • Altering season of use (avoid grazing the same plants at the same time year after year)
  • Animal exclusion
  • Activities to minimize ground disturbance, especially in riparian areas
  • Preventing weed seed transportation on animals, humans, or equipment
  • Maintaining healthy, weed-free vegetation (consider proper stocking rates and allow plant recovery before regrazing)
  • Managing weed infestations to limit weed seed dispersal into weed-free areas
  • Revegetation of sites susceptible to weed invasion
  • Frequent and systematic monitoring for new weeds
  • Reporting and follow-up management
  • Ensure grazing allotment permittees are aware of the impacts of weeds and can identify weeds threatening the management area.

Avoid or remove sources of weed seed and propagules to prevent new weed infestations and the spread of existing weeds. Minimize transport of weed seed into and within allotments.

• If livestock may contribute to seed spread in a weed-infested area, schedule livestock Use for prior to seed-set or after seed has fallen.
• Consider grazing domestic sheep on weed-infested sites during early summer to minimize flower and seed production of weeds. Schedule cattle grazing after sheep when desirable grasses have matured and dispersed seeds.
• If livestock were transported from a weed-infested area, annually inspect and treat entry areas for new weed infestations.
• Avoid moving livestock from weed-infested sites to weed-free rangeland.
• Close infested pastures to livestock grazing when grazing will either continue to exacerbate the condition or contribute to weed spread. Designate those pastures as unsuitable range until weed infestations are adequately managed.
• Provide supplemental feeding in a designated area so new weed infestations can be detected and treated quickly. Pelletized feed is unlikely to contain viable weed seed.
• Weed seed can be introduced into weed-free rangeland by passing through the digestive tracts of livestock. Keep new livestock (especially livestock that may have been fed poor quality hay) in a holding field for 24 to 48 hours before releasing onto open range.

Maintain healthy, desirable vegetation that resists weed invasion, establishment, and growth.

• Manage the timing, intensity (utilization), duration, and frequency of livestock activities to maintain the vigor of desirable plants and retain live plant cover and litter to minimize exposed soil.
• Manage livestock grazing in restoration areas to ensure that desired vegetation is well established. This may involve animal exclusion for at least two years. Consider practices to minimize wildlife grazing such as temporary fencing, if necessary.
• Reduce ground disturbance. Consider changes in the timing, intensity, duration, or frequency of livestock use; location and changes in salt grounds; restoration or protection of watering sites; and restoration of yarding/loafing areas, corrals, and other areas of concentrated livestock use.
• After moving salt, consider revegetating the old salt ground by raking the site before and after broadcast seeding, then fencing the site until seedlings are well established. Note that compacted soil may require scarification before broadcast seeding.
• Inspect areas of concentrated livestock use for weed invasion. Inventory and manage new infestations.

Improve effectiveness of weed prevention practices through awareness programs and education. Promote weed awareness and prevention efforts among range users.

• Use education programs or annual operating instructions to increase weed awareness And prevent weed spread associated with livestock management.
• Agency land managers may consider loaning small GPS units to permittees who can Then document weed locations on their allotments.

Wildlife

Avoid creating bare ground or soil disturbances that promote weed invasion, growth, and establishment.

• Periodically inspect and document areas where wildlife concentrate in the winter and spring that might result in overuse or soil scarification.
• Use weed-free materials at big game baiting and feeding stations.

Outfitting and Recreation

Avoid moving weed seeds or propagules into the backcountry.

• Noxious weeds can be introduced in livestock dung. Feed pack and saddle stock only weed-free feed for several days before traveling into the backcountry.
• Inspect, brush, and clean animals (especially hooves and legs) before entering public land. Inspect and clean tack and equipment.
• Enter public trails with clean shoes and clothing. Clean dogs if there is a possibility they are carrying weed seeds. Wearing gators when hiking in weedy areas can greatly reduce the chance of picking up weed seeds in socks and shoelaces.
• Do not pick "wildflowers" unless they are distinctly identified and plant-harvesting is allowed. Invasive weeds often bloom with pretty flowers.
• Thoroughly clean bicycles prior to using public trails.
• Provide weed identification information at trailheads. Encourage trail-users to hand-pull and bag taprooted weeds when found. Note that hand-pulled weeds should not be discarded along the trail because seed could still be produced.
• Regularly inspect trailheads and other staging areas for backcountry travel. Bedding in trailers and hay fed to pack and saddle animals may contain weed seed or propagules.
• Tie or hold stock in ways that minimize soil disturbance and avoid loss of desirable native vegetation.
• Authorized trail sites for tying horses should be monitored several times per growing season to quickly identify and eradicate new weeds. Trampling and permanent damage to desired plants are likely. Tie-up sites should be located away from water and in shaded areas where the low light helps suppress weed growth.
• Use weed-free forage or pelleted feed in the backcountry.

Invasive Plant Prevention: Fire

Wildfires require immediate action. Therefore, it's important to plan weed management strategies, prepare equipment, and educate firefighters before emergency situations strike.

Fire Planning

Improve effectiveness of prevention practices through weed awareness and education.

• Increase weed awareness and weed prevention in all fire training. Note that fires can increase soil nitrogen, decrease shade, and decrease competition from desirable plants - all conditions that favor weed invasion.
• Provide weed identification aids.
• For prescribed burns, inventory the project area and evaluate potential weed spread with regard to the fire prescription. Areas with moderate to high weed cover should be managed for at least two years prior to the prescribed burn to reduce the number of weed seeds in the soil. Vigilant weed management will be necessary after the burn.
• Ensure that a weed specialist is included in a Fire Incident Management Team when wildfire or control operations occur in or near a weed-infested area.

Avoid or remove sources of weed seed and propagules to prevent spreading weeds.

• Use operational practices to reduce weed spread (for example, avoid weed infestations when locating base camps, helibases, and staging areas).
• Locate and treat weeds in practice jump areas.
• Maintain the network of airports, helibases, camps, and staging areas in a noxious weed-free condition.

Fire-Fighting

Avoid or remove sources of weed seed and propagules to prevent new weed infestations and the spread of existing weeds.

• Ensure that all equipment has been thoroughly cleaned and is free of weed seed and propagules.
• Designate equipment-cleaning sites. Inspect and treat weeds that establish at equipment cleaning sites after fires.
• When possible, use fire suppression tactics that reduce disturbances to soil and vegetation.
• Avoid moving water buckets from aquatic-weed-infested lakes to lakes that are not infested. There is no hazard in using water infested with aquatic weeds on terrestrial sites.
• Given a choice of tactics, avoid ignition and burning in areas at high risk for weed establishment or spread.

Fire Rehabilitation

To prevent conditions favoring weed establishment, as soon as possible after a fire revegetate disturbed ground that is unlikely to recover to desired plants naturally. Use certified weed-free seed mixes.

• To prevent weed spread, treat weeds in burned areas. Weeds can recover as quickly as two weeks following a fire.
• Weed-free or relatively weed-free burned areas should be monitored for weeds the following growing season.
• Determine soon after a fire whether revegetation is needed to speed recovery of a competitive plant community, or whether desirable plants in the burned area will recover naturally. Consider the severity of the burn and the proportion of weeds to desirable plants on the land before it burned. In general, more severe burns and higher pre-burn weed cover increase the necessity of revegetation. Consider revegetating an area if the desired plant cover is only 20 to 30%.
• Monitor, document, and treat weeds at fire access roads, cleaning sites, fire lines, staging areas, and within burned areas. Control infestations to prevent spread within burned areas; control nearby infestations to prevent spread into burned areas.
• Seed and straw to be used for burn rehabilitation (for wattles, straw bales, dams, mulch, etc.) should be certified free of weed seed and propagules.
• Defer livestock grazing in burned areas until vegetation has successfully reestablished, usually after two growing seasons. Restrict travel to established roads to avoid compacting soil that could hinder the recovery of desired plants.
• Request that a weed specialist review burned area rehabilitation reports to ensure proper and effective weed prevention and management is addressed.
• Develop a burned-area integrated weed management plan, including a monitoring component to detect and eradicate new weeds early.

1 This guide is based on the USDA Forest Service "Guide to Noxious Weed Prevention Practices." Thanks to reviewers Steve Dewey (Utah State University), Kim Goodwin and Roger Sheley (Montana State University), Tony Svejcar (USDA Agricultural Research Service), and Steve Radosevich (Oregon State University); and to Rita Beard (USDA Forest Service) for initiating this compilation. This material was made possible, in part, by a grant from the United States Department of Agriculture (USDA). It may not necessarily express USDA views.1

Suggested Construction Contract Wording for Weed Prevention

Note: This section is provided as an example of language that can be included in construction contracts when appropriate to help prevent the spread of weeds. Nevada Revised Statutes Chapter 555 advises that the control of noxious weeds is the responsibility of every landowner or occupant. This suggested contract wording can be modified as needed to fit individual projects.

Prior to any construction disturbance you will:

• Identify and map all noxious and invasive weed populations present in the project area
• Treat or contain any weed populations that may be impacted or disturbed by construction activity
• Flag all weed populations to be avoided
• Provide training to construction workers and equipment operators on the identification of weeds to be avoided
• Certify that all construction material sources used for supplies of sand, gravel, rock and mulch are weed-free prior to obtaining or transporting any material from them
• Obtain and use only certified weed-free straw or use fiber roll logs for sediment containment
• Wash and inspect all vehicles for weed seeds and plant parts prior to bringing them onto the job site
• Install stormwater Best Management Practices to prevent erosion of the job site and the potential transport of weedy material onto or off of the job site

During construction you will:

• Minimize ground disturbance and vegetation removal as much as possible and practical
• Wash, or using an air compressor, blow clean all vehicles (including tires and undercarriage) that may have entered weed-infested areas prior to entering uninfested areas of the job site
• Restrict vehicles or other traffic that may transport weed seeds or plant material from entering the job site unless they are first washed and inspected.

After construction is complete you or the property owner will:

• Revegetate or otherwise prevent the establishment of weeds in all areas of the job site through a program of monitoring and post-construction weed treatment for the life of the project
• Revegetate using soil components and mulches obtained from non-weed infested sources
• Utilize seed and other plant materials that has been checked and certified as noxious weed-free and that has a weed content of 0.05 percent or less
• Revegetate using plant materials that have a high likelihood of survival
• Maintain all planted material and native vegetation located on the project site for the life of the project

References:

California Bureau of Land Management. 2003. Weed Management and Prevention Guidelines for Public Lands. http://www.ca.blm.gov/pa/weeds/weedprevent.html

Center for Invasive Plant Management. 2003. Guidelines for Coordinated Weed Management of Noxious Weeds: Development of Weed Management Areas, Section IV: Prevention and Early Detection and Appendix 1:Sample Contracts, Agreements and Memorandums of Understanding. http://www.weedcenter.org/management/guidelines/tableofcontents.html

Colorado Bureau of Land Management. 1991. Prototype Weed Prevention Measures. http://www.co.blm.gov/botany/lolostip.htm

Lewis County Noxious Weed Control Board. 2003. Weed Prevention. Washington State University Cooperative Extension. Lewis County, Washington.

Sheley, Roger and Kim Goodwin. 2000. Plan Now For Noxious Weed Invasion. Montana State University.

Sheley, R., M. Manoukian and G. Marks. 2000. Preventing Noxious Weed Invasion. Pp. 69-72 in: Biology and Management of Noxious Rangeland Weeds, ed. R.L. Sheley and J.K. Petroff. Oregon State University Press, Corvalis, Oregon.

Trainor, Meghan and A.J. Bussan. 2000. Integrated Weed Management; Preventing Weed Invasion. Montana State University Extension.

For more information, contact:
University of Nevada Cooperative
Extension PO Box 11130,
Reno, NV 89520
(775) 784-4848
Nevada Department of Agriculture
350 Capitol Hill,
Reno, NV 89502
(775) 688-1180 Ext. 269

Early Detection and Rapid Response

Even the best prevention efforts cannot stop all introductions. Early detection of incipient invasions and quick, coordinated responses are needed to eradicate or contain invasive species before they become too widespread and control becomes technically and/or financially impossible. Populations that are not addressed early may require costly ongoing control efforts.
-National Invasive Species Management Plan, 2001

Although early detection and rapid response are important elements of invasive species management, currently there is no comprehensive national system for detecting, responding to, and monitoring incipient invasions. Inadequate planning and technologies, jurisdictional issues, insufficient resources and information currently hamper early detection and rapid response efforts in many locations. Key elements needed in an early detection and rapid response system include:

1. access to up-to-date reliable scientific and management information;
2. facilitate rapid and accurate species identification;
3. establish a standard procedure for rapid risk assessment;
4. provide new and enhanced mechanisms for coordinating the efforts of Federal, State and local agencies, tribal governments, and private entities; and
5. provide adequate technical assistance (e.g., quarantine, monitoring, information sharing, research and development, and technology transfer) and rapid access to stable funding for emergency response efforts, including funding for accelerated research of invasive species biology, survey methods, and eradication options.

The system's success will depend in part on public participation in efforts to report and respond to invasions.

As pointed out in the National Invasive Species Management Plan, currently there is no comprehensive national system for Early Detection and Rapid Response (EDRR). Land managers working at smaller landscape scales or more local levels should consider instituting some form of an EDRR effort on the lands that are the focus of their invasive plant management efforts. The following may provide an overview for doing so:

Early detection of non-indigenous species should be based on a system of regular surveys to find newly established species. However, not all species will become established, and only a small percentage of those that do will become invasive, presenting threats to biodiversity and the economy. Thus, some surveys will need to focus on specific target species known to be invasive under similar conditions or species that have been successfully eradicated before. In addition, site-specific surveys looking for alien species in general can be carried out. They should be targeted at key sites, e.g. areas of high conservation value, within the range of highly endangered species, and at high-risk entry points such as airports and harbors (logging roads, trail heads, parking lots, etc.). The drawback of these general surveys is that only well-trained staff will be able to identify non-indigenous species in many taxonomic groups.

Staff responsible for the surveys needs to be trained. Public education should focus on groups using or acquainted with the natural environment, such as farmers, tour operators, and the concerned public. This education campaign can be based on media promotion, displays, and personal interactions. The training of survey staff must include development of taxonomic knowledge, use of databases and identification services, and survey methods for the different groups.

A crucial part of early detection is a contingency plan, which determines the action to be taken when an alien species is been found. Given the diversity of potential new incursions, an initial plan will be rather general. It should summarize the stakeholders and experts who need to be contacted for a more detailed action plan. Contingency plans targeted at specific high-risk species can be very efficient, with an exact schedule for what to do.

Monitoring for Prevention and Early Detection

The information presented above provides guidance on what you as a land manager can be doing on a day-to-day or project-to-project basis to prevent invasions of exotic species. The following may help in viewing prevention and early detection in a broader context. Developing specific programs or plans to incorporate a prevention and early detection effort into a broader management context.

Exotic plant invasions often follow a typical pattern. Seeds or plant fragments arrive by various mechanisms and become established; however, the persistence of these new individuals is tenuous because of unsuitable habitat or low population levels. If the exotic plant invaders persist, it takes some time (the lag phase) for the population to increase in size. Only after a time specific to species and habitat has elapsed does the population suddenly expand. Control efforts are most cost-effective and likely to succeed during this lag phase.

Thus the early detection of newly arriving exotic plant species is an important component of a control program. Unfortunately, these newly establishing populations are rare and consequently difficult to detect.

This section identifies goals, objectives and guidelines to prevent new introductions and detect new populations early in the establishment phase. When applying the information presented in this section, it is important to:

• Work outside of agency boundaries to manage at a landscape scale. Identify a buffer zone which, when adequately managed in cooperation with partners, will more effectively accomplish invasive species management goals.
• Integrate efforts with ongoing projects in the agency/network/area and with other agencies (vegetation mapping, exotic plant management areas). Data from these efforts broaden a surveillance system
• Where possible, standardize prevention and detection programs across agency holdings within a network or ecoregion.
• Keep abreast of newly emerging surveillance and sampling design strategies to make programs more effective and efficient. This may involve stepping outside of the mainstream land management and conservation disciplines (e.g. novel sampling designs from oil and mineral exploration literature).
• Consider that integrated monitoring can be developed across multiple scales: forestry lands, parks, game lands, subunit, buffer zone around park or forestry lands, and region.
• Consider that one role of inventory and monitoring is to provide relevant information to determine appropriate management action along a continuum (e.g. prevention, detection, eradication, containment, suppression, or no action) for an invasive, vascular plant species or conservation value (e.g. site, native species, assemblage or ecosystem function).
• Integrate monitoring for prevention and early detection goals and guidelines with ongoing inventory, monitoring and research efforts.
• Develop a sound information base for invasive exotic plants; control can only be achieved by acting at multiple spatial scales and in regional partnerships. This information can be used by park managers acting in concert with multiple agencies to develop new strategies for stemming the tide of alien invasions.

References:
Hobbs, Richard J. and Stella E. Humphries. 1995 An integrated approach to the ecology and management of plant invasions. Conservation Biology 9(4): 761-770.

Prevention and Early Detection in PA

Prevention and Early Detection activities can be focused at different scales. A land manager of a 2,000-acre state park may be limited to focusing prevention efforts on that specific landscape. Invasive species may be well established in other parts of the region or state, but may be new to the 2,000-acre state park. On the other hand, land managers may have the ability (i.e., resources) to work beyond the borders of their state forest or state park. Having this larger focus will result in greater success in keeping unwanted species off protected natural lands.

Another focus for Prevention and Early Detection activities is on species that are not yet well-established in Pennsylvania or a region of Pennsylvania (e.g., eastern PA or western PA). In addition to known species, there are a number of species that experts believe may be future problems for PA's natural areas. These species have been observed acting invasively in natural settings in other parts of the Mid-Atlantic region. Of greatest concern are invasions in bordering states with similar habitats.We consider these species Watch List species.

To understand what species should be the focus of any Prevention or Early Detection efforts in PA, go to Invasive Exotic Plants in Pennsylvania List and the Watch List.

The PA-DCNR Invasive Species Management Plan addresses both Prevention and Early Detection needs in PA. Specific recommendations, in terms of education are identified in the plan. Early Detection is addressed under the Survey and Detection Section. A discussion of Early Detection programs for forest pests (insects) is included, as well as some work that has been done within the agency on invasive plants. A more formalized plan for invasive plants is needed for Pennsylvania's public and private lands.

Also included under this section of the Management Plan is an introduction to Hazard Analysis Critical Control Point (HACCP) (planning. The U.S. Fish and Wildlife Service employs this to examine common practices that might be altered to reduce the risk of invasive species introduction. DCNR is conducting a pilot project that will apply principles HACCP to preventing invasive species introduction at oil and gas lease sites (see DCNR Invasive Species Management Plan). If the pilot project shows the approach to be feasible for DCNR, it can be incorporated more widely into operations and programs. This procedure for preventing invasives does not require each individual land manager to have detailed knowledge of the site's invasive species and it can help us focus monies and energy most effectively.

Voluntary Codes of Conduct - The St. Louis Declaration

Another step that can be taken by DCNR or any other land management agency is to adopt the Voluntary Codes of Conduct as presented under the St. Louis Principles (see http://www.centerforplantconservation.org/invasives/codesN.html)

In December 2001, experts from across the globe met in St. Louis, Missouri to explore and develop workable voluntary approaches for reducing the introduction and spread of non-native invasive plants, which are serious threats to protecting biodiversity and ecosystems in the United States and other countries. The Workshop on Linking Ecology and Horticulture to Prevent Plant Invasions was convened by the Missouri Botanical Garden and the Royal Botanic Gardens, Kew; and brought together some of the most respected leaders in their fields for the first time.

This landmark three-day gathering yielded the Saint Louis Declaration, which consists of two major components:

1. Overarching Findings and Principles that frame the invasive species problem and present the underlying basis for successful efforts to address it; and,
2. Draft Voluntary Codes of Conduct that help govern decisions made by commercial, professional and government groups whose actions affect the spread of invasive plant species including government agencies, nursery professionals, the gardening public, landscape architects and botanic gardens and arboreta.

Draft Voluntary Codes of Conduct that help govern decisions made by commercial, professional and government groups whose actions affect the spread of invasive plant species including government agencies, nursery professionals, the gardening public, landscape architects and botanic gardens and arboreta.
The following findings and principles were agreed upon by the entire St. Louis assemblage:

Findings

• People are major dispersers of plants.
• The magnitude of this dispersal is unprecedented and has allowed dispersal of species that manifest aggressive traits in new areas.
• Plant introduction and improvement are the foundation of modern agriculture and horticulture, yielding diversity to our supply of plants used for food, forestry, landscapes and gardens, medicinal and other purposes.
• A small proportion of introduced plant species become invasive and cause unwanted impacts to natural systems and biological diversity as well as economies, recreation and health.
• Plant species can be invasive in some regions, but not in others.
• The impacts of invasive plant species can occur at times and places far removed from the site of introduction.

Principles (a.k.a. The St. Louis Six):

1. Plant introduction should be pursued in a manner that both acknowledges and minimizes unintended harm.
2. Efforts to address invasive plant species prevention and management should be implemented consistent with national goals or standards, while considering regional differences to the fullest extent possible.
3. Prevention and early detection are the most cost effective techniques that can be used against invasive plants.
4. Research, public education and professional training are essential to more fully understanding the invasive plant issue and positively.
5. Individuals from many fields must come together to undertake a broad-based and collaborative effort to address the challenge, including leaders in horticulture, retail and wholesale nurseries, weed science, ecology, conservation groups, botanical gardens, garden clubs, garden writers, educational institutions, landscape architects, foundations and government.
6. A successful invasive plant species strategy will make use of all available tools including voluntary codes of conduct, best management practices, and appropriate regulation. Codes of conduct for specific communities of interest are an essential first step in that they encourage voluntary initiative, foster information exchange, and minimize the expense of regulation.

The voluntary codes offer professional codes of conduct designed to curb the use and distribution of invasive plant species through self-governance and self-regulation by the groups concerned. This approach has been used successfully to ameliorate other problems but its application to invasive plant threats is novel and innovative. Importantly, the Voluntary Codes of Conduct were developed recognizing that education must accompany all efforts to address the problem and that some future government regulation may perhaps be needed if such efforts prove insufficient. These codes are now being considered for endorsement by the major professional societies and organizations representing each of the groups covered. If endorsed they will be "tested" and revised as necessary to improve their utility and effectiveness.

The following codes of conduct may apply to DCNR and other state land management agencies:

Voluntary Codes of Conduct for Government

• Require risk assessment for government-led or financed plant introductions to ensure that no new harmful plant species are introduced, intentionally or unintentionally.
• Do not distribute existing holdings of invasive plant species to areas where they can potentially do harm; eliminate these holdings or maintain new or existing holdings using appropriate safeguards.
• Coordinate and facilitate collaboration in databases, early warning systems, monitoring, and other means of preventing invasive plant species problems.
• Lead and fund (subject to budgetary considerations) the development of environmentally sound methods to control harmful invasive plant species, seek control of such species on public lands and promote their control on adjacent private lands.
• Develop and promote the use of non-invasive plant species within all government units and to the public
• Facilitate, lead, coordinate and evaluate public outreach and education on harmful invasive plant species.
• Encourage the employees and management participate in ongoing training programs on invasive plant species.
• Foster international cooperation to minimize the risk of the import and export of potentially invasive plant species.
• Develop partnerships and incentive programs to lessen the impact of invasive plant species and provide non-invasive restoration materials.
• Provide a forum for regular evaluation of the effectiveness of these voluntary codes of conduct towards preventing the invasive plant species problem.
• Enforce invasive plant species legislation at all levels.

Voluntary Codes of Conduct for Nursery Professionals

• Ensure that invasive potential is assessed prior to introducing and marketing plant species new to North America. Invasive potential should be assessed by the introducer or qualified experts using emerging risk assessment methods that consider plant characteristics and prior observations or experience with the plant elsewhere in the world. Additional insights may be gained through extensive monitoring on the nursery site prior to further distribution.
• Work with regional experts and stakeholders to determine which species in your region are either currently invasive or will become invasive. Identify plants that could be suitable alternatives in your region.
• Develop and promote alternative plant material through plant selection and breeding.
• Where agreement has been reached among nursery associations, government, academia and ecology and conservation organizations, phase-out existing stocks of those specific invasive species in regions where they are considered to be a threat.
• Follow all laws on importation and quarantine of plant materials across political boundaries.
• Encourage customers to use, and garden writers to promote, non-invasive plants.

Voluntary Codes of Conduct for Landscape Architects

• · Seek our education and information on invasive species issues
  • Work with local plant ecologists, horticulturists, nurseries, botanic gardens, conservation organizations and others to determine what species in your region either are currently highly invasive or show aggressive potential. Investigate species under consideration that may present a threat.
  • Increase interaction with other professionals and non-professionals to identify alternative plant material and other solutions to problems caused by harmful invasive plants.
  • Take advantage of continuing education opportunities to learn more about invasive species issues.
• Identify and specify non-invasive species that are aesthetically and horticulturally suitable alternatives to invasive species in your region.
• Eliminate specification of species that are invasive in your region.
• Be aware of potential environmental impacts beyond the designed and managed area of the landscape plan (e.g. plants may spread to adjacent natural areas or cropland).
• Encourage nurseries and other suppliers to provide landscape contractors and the public with non-invasive plants.
• Collaborate with other local experts and agencies in the development and revision of local landscape ordinances. Promote inclusion of invasive species issues in these ordinances.

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