Download Invasive Weeds Project 2008

Giant Hogweed
Japanese Knotweed
Himalayan Balsam
Financial supporters of the Invasive Weeds Project.
Funding.
 ART secured funding over two years to research the status
of invasive weeds in Ayrshire and to implement control
measures.
 Phase 1. 2008.
Survey of the Rivers Ayr, Irvine, and Girvan. Spraying of
GHW on the upper River Ayr.
 Phase 2. 2009.
Survey of the Rivers Garnock, Doon and Stinchar. Ongoing
control of GHW on the River Ayr.
About the species:
 GHW originated in the Caucasus, JK in the far East and HB in
the Western Himalayas.
 All were introduced to UK in the early 19th C. as ornamental
plants, quickly spreading out of control.
 The Wildlife and Countryside Act 1981, makes it an offence to
plant, cause to grow or spread GHW and JK in the wild. Waste
plant material and contaminated soil is regulated under the
Environmental Protection Act 1990.
 HB Recommended for inclusion under schedule 2 of the Wildlife
and Countryside Act 1981.
Giant Hogweed.
Below.
GHW in flower on the Lower Irvine.
Right.
GHW about to flower on River Ayr.
Below Right. GHW on the banks of the Water of Coyle.
Japanese Knotweed
Above.
Top Right.
Right.
Monoculture. Glaisnock Water, Cumnock Town Centre.
Mature plants. Hollow Bamboo like stems.
Broken stems creating an obstruction.
Himalayan Balsam
Above.
Top Right.
Right.
Attractive plant in flower.
HB on the lower R. Irvine
Extensive monoculture in high summer.
Problems associated with Invasive Weeds.
Giant Hogweed:
 Causes Photo sensitive dermatitis in humans. Health and safety
issues for those involved in control. Highly attractive to children
(used as telescopes etc.) Can cause permanent blindness.
 Monoculture- excludes native species, bare soils in winter, prone
to erosion, contributing to diffuse pollution. Rapid spread
downstream (up to 50,000 seeds/plant).
Problems associated with Invasive Weeds,
cont.
Japanese Knotweed:
 Reproduces from fragments of vegetative material
(shoot/root) but not seed.
 Forms monoculture, excludes native species, bare soils in
winter, prone to erosion, contributing to diffuse pollution.
 Blocks drains, penetrates tar, concrete, foundations etc.
Damages flood defences and can alter river flows leading to
flooding.
 Planning constraints, increased development costs,
reduced land values. Plant material and contaminated soil
must be treated as controlled waste.
 Difficult to eradicate & control.
1993 GHW survey of River Ayr.
G. Tiley & B. Philp (SAC)
Summary of the current situation:
 GHW is perhaps the highest priority species due to the
human health issues.
 Eradication will depend on developing a sustained
programmed of control including all stakeholders.
(Local Authorities, Angling Clubs, Land Owners etc.)
 South Ayrshire Council are controlling GHW on lower
Rivers Ayr. This will have limited long-term benefit
without upstream control.
summary:
 Japanese Knotweed is so extensive and persistent that
eradication is impractical/improbable/impossible?
 Targeted control of new outbreaks in previously
unaffected areas is essential. Rapid Response.
 Ongoing monitoring of all species on all catchments is
required.
 ART are ideally positioned to be the lead partners in
any strategic plan.
A Final thought.....
 In 1992, Tiley & Philp recognised the urgent need for
control of GHW.
 SAC quoted Kyle and Carrick and Cumnock and Doon
Valley District Councils a combined rate of £13000 to
attempt to reduce GHW to negligible levels (if not
eradicate it)on the River Ayr.
 No action was taken.
 The cost of this decision in financial and environmental
terms?