Invasive Weeds; A barrier to development. Environmental catastrophe or manageable

nuisance?

A TCM Presentation

Thurlow Countryside Management

• UK’s largest Invasive Vegetation Specialist

• Successfully completed 2,500 remediation projects

• Built on providing quality customer service and innovative, flexible solutions researched through TCM R & D

• Integrated Management System since 2006 including

– BN ISO 14001:2004 (Environmental standard)

– BN ISO 9001:2008 (Quality standard)

– BN OHSAS 18001:2007 (Health & Safety standard)

• Commitment to continuous improvement within all these areas through accreditation systems

• Proactively work with customers to minimise risk

Issues covered today:• Legislation & Responsibility

• Why eradicate?

• What’s the plan?

• Treatment methods

• Case Study 1: Dolcoath, Camborne, Cornwall

• Case Study 2: Olympic Park, Stratford

• Case Study 3: National Grid Properties

• GIS Mapping

• What NOT to do

Legislation and Responsibility

•The Wildlife and Countryside Act 1981 provides the primary

control on the release of non-native species into the wild in Great

Britain. It is an offence under Section 14(2) of the Act to “plant or

otherwise cause to grow in the wild” any plants listed in Schedule 9,

Part II.

•Controlled Waste Regulations 1992 – Schedule 3 Part 6

defines all “arisings from tunnelling or excavations” as Controlled Waste

•Environmental Protection Act 1990 - Part II A Sets out

businesses’ ‘duty of care’ responsibilities for producing, collecting, disposing of or treating controlled waste.

•Environmental Permitting Regulations 2010 ( formerly the Waste Management Licensing Regulations) –implementing restrictions on treatment process regarding contaminated material

Other Acts include:

Site Waste Management Plans Regulations 2006 Town and Country Planning Act 1990The Landfill (England and Wales) Regulations 2002Weeds Act 1959Ragwort Act 2003Highways Act 1980Water Resources Act 1991CROW Act

Legislation and Responsibility

So what is the aim of Japanese knotweed

treatment?

Without creating this…..

What’s the plan?

When considering available treatment options consider the

following:

•The ultimate aim - Eradication or control?

•The size of the problem – catchment scale?

•Timescale – when does it need to be gone?

•The surrounding environs – what will replace/be harmed?

•Budget – probably the main control

Methods of treatment for Invasive Weeds

Herbicide treatment:

•Beside water?•Desirable vegetation?

•Neighbours?•Timescale?

•Subsequent site use?

Excavation:•Removal from site?

•Burial on site?•Screening?

•Services?•Boundaries?

Herbicide techniques

• Can achieve control or eradication

• Cost effective compared to excavation

• Can limit options if ineffective especially regarding

Japanese knotweed

• Time requirement

Herbicidal treatment of Japanese Knotweed

Fallopia japonica

• Single season treatment – residual chemicals, adjuvants and wetters

• 2-3 year treatments – glyphosate based chemicals

• Stem injection - Average JK stand 20 stems/m2 20 x 2ml = 40ml per m2 resulting in 40 litres of chemical per hectare

• Maximum amount allowed to spray conventionally = 5 litres in open land and 10 litres in forestry (depending on the label)

Single Season Herbicidal; including TCM in situ system

•Reduced chemical usage, minimum of 5 visits

•Successful on over 1500 sites

•Takes just one growing season - Complements development plans

•Cultural and chemical based methodology

•Treats Knotweed without disturbing roots and rhizomes

•Overcome boundary issues

•Most cost effective solution

•Underwritten with specific P.I. insurance

Single season treatment

Glyphosate based treatment – non residual, non selective herbicide

• 2-3 years minimum treatment required with likely annual spot treatment thereafter

• Only likely to give control – knotweed stands in Cornwall first treated in 2000 are still alive

• Restricts leaf size

• Non selective herbicide suitable for use on water (provided it says so on the label and a WQM1 has been approved by EA)

Case studies

Case study 1: Dolcoath, Camborne, Cornwall

• First contacted by Pell Frischmann January 2007

• Established that Japanese Knotweed covered approx 6500m2 area across the site in over 50 separate stands

• Established that Giant Horsetail covered approx 800m2

• Treatment to JK pre 2006 had included herbicide applications followed by excavation and mass disturbance

• All plants where bonsai, mutated and damaged

• Trial pits had been excavated and refilled with rhizome contaminated material to a depth of 4 metres

Case study 1: Dolcoath, Camborne, Cornwall

Site issues:

• Development of the site required during 2008

• All soil on site contaminated with heavy metals resulting in an increased cost to remove from site

• Mining features including 20 shafts requiring capping present

• Requirement to strip back the top soil and subsoil to bedrock to stabilise known and unknown mining features (approx 6 metres deep across the knotweed areas)

• Significant shortfall of material to establish correct site levels – no material could be removed from site

Case study 1: Dolcoath, Camborne, Cornwall

Problem solved:

• Bespoke methodology developed to clean soil and retain material

on site

• Machinery developed in order to breakdown soil to allow the removal of the viable rhizome

• 160,000 tons of soil where processed over a 7 month period

• Processed soils where reinstated throughout the entire site area

• Follow up herbicide regime during 2009/10 treated 27 individual

plants

Case Study 2: Olympic Park

• Japanese Knotweed, Giant Hogweed and Himalayan Balsam identified in numerous locations throughout North Park and SouthPark

• A fairly obvious deadline!

• Levels of other contaminants fluctuated within the knotweed areas

• Major soil movement/cut and fill operation required

• Valuation figures for eradication of the JK were estimated to be £8m on Northern Park alone if disposal at landfill

• Other contaminants present meant that it would need to be disposed of as hazardous waste

Case Study 2: Olympic Park

• Specification that only 5% waste could be taken off ENTIRE site

• Aquifer and rivers on site restricted types of herbicide available extending time period required to treat some waterside areas

• As construction programme was refined, decision taken to soil screen initially on North Park and then on South Park to allow development to meet deadlines

• Significant areas treated with herbicide using TCM HIT Single Season treatment

Case Study 2: Olympic Park

Knotweed treatment:

• Total weight screened in the region of 126,000 tonnes

– Used reduced excavation technique

– Equals 6,300 lorry loads @ 20 tonnes per load

Environmental and Monetary Savings

• Environmental and monetary cost of soil screening can be a fraction of excavation and removal to landfill

– Reduced carbon footprint as reduced/no haulage to landfill

– Can negate need to import topsoil

– Could qualify for Land Remediation Tax Relief as treatment on site

Case Study 3: Commonwealth Games Athletes Village

• Soil screening of Japanese knotweed May 2010,6 weeks duration – approx 8000m3

• Herbicide treatment May 2012 (2 years)

• Due to the presence significant infestations of Giant

Hogweed on the banks of the River Clyde, a 2 year

herbicidal treatment programme using TCM’s HIT Methodology is being undertaken.

GIS Mapping – knowledge is everything

In summary

• Although perceived as expensive there is always a way to treat all invasive plant species

• Early identification is KEY

• Herbicides, membrane and machinery DON’T kill

Invasive weeds – PEOPLE DO.

• People undertaking inadequate, unproven and poor

practices make the problem worse

What not to do……..

Don’t just carry on regardless…..

Burning doesn’t work…..

Health and safety considerations……

Doing ‘something’ is not always doing the RIGHT thing

£4 handheld spray can of herbicide from Focus DIY

Resulting in Dig and dump – cost of £18,500