Invasive Rhododendron – what’s in a name?

14d5da19ea8-98dbced4df5ccbfc2462b56473d9542c.1400Rhododendron ponticum is the name commonly used for the invasive purple rhododendron frequently found growing wild in the British countryside. In itself, a nice shrub in its season, but it has the ability to spread by seeds or layers and can regrow from roots or small parts of the stem so it is difficult to eradicate. On acidic soils in areas with high rainfall, it spreads rapidly, and can quickly form a ground-covering monoculture, smothering native species. It has also recently become a susceptible to a number of toxic fungi, which then spread with it to infect woodlands, leading to greater efforts to eradicate it.

As a result of this, Rhododendron ponticum appears in Schedule 9 of the Wildlife and Countryside Act 1981, making it an offense to cause it to grow in the wild – an obvious precaution against further spread. But WACA 1981 also makes it an offense to offer the plant for sale, or to possess viable plant material (including seeds) for the purposes of sale – a major problem for garden centres up and down the country who all offer R.ponticum varieties as garden plants.

As a result effort has been made to try to differentiate the invasive plant from the garden varieties, with Cullen in 2011 suggesting that the invasive plant was a “hybrid swarm” to which he ascribed the name R. x superponticum. However DNA testing has revealed that the common UK invasive plant is derived from the wild native populations of R. ponticum in the Iberian Peninsula (which shares its propensity to spread) and distinct from the native  R. ponticum population in the Caucasus (which does not spread as freely) and from which many of our non-spreading garden varieties have been developed.

On the basis of this finding, it has been suggested that the invasive Rhododendron common in the UK (and also found in the Iberian Peninsula)  is named Rhododendron ponticum spp. baeticum, making it distinct from the garden varieties bred from Rhododendron ponticum spp. ponticum (the Caucasus species), neatly solving the legal tangle of the species being sold in the garden centres. Hopefully, if this distinction becomes widely recognised, WACA 1981 Schedule 9 will be updated with the specific name, and the issue of it’s sale in garden centres will finally go away!

Just as a footnote, it’s worth remembering that before the last Ice Age, R. ponticum was widespread as a native plant in the UK and much of northern Europe, and it’s only with the changing climate as the ice advanced that it was eradicated from our shores. Had not the changing sea levels submerged the land bridge as the ice retreated, we might now be considering this population to be a “troublesome native species” rather than the “invasive non-native species” it is now branded!



UKCG Environmental Training Standard

The UKCG Environmental Training Standard  was published in July 2015, and recognises the leadership role that UK Contractors Group member companies play in driving best practice within the construction sector. It sets down the minimum training expected for individuals to undertake their roles on member’s sites to be able to demonstrate their competency through formal environmental training, including the CITB SEATS course.

This document sets down the standard of environmental training applicable to those who manage, supervise or undertake construction related activities as follows:

Site Managers (including those employed by supply chains):

  1. CITB SEATS+ Course (SEATS plus additional management modules); or
  2. A comparable external course approved by the UKCG Environmental Training Task Group; or
  3. An internally developed course that can demonstrate training outcomes comparable to 1 and 2 above.

The training must last a minimum of TWO DAYS, include a form of assessment, and a completion certificate. Refresher training must be carried out at intervals not exceeding five years.

Site Supervisors (including those employed by supply chains)

  1.  CITB SEATS Course; or
  2. A comparable external course approved by the UKCG Environmental Training Task Group; or
  3. An internally developed course that can demonstrate training outcomes comparable to 1 and 2 above.

The training must last a minimum of ONE DAY, include a form of assessment, and a completion certificate. Refresher training must be carried out at intervals not exceeding five years.

Site Operatives (including those employed by supply chains)

A relevant competency scheme card including the CITB Health Safety & Environment Test where required, and renewed as necessary.

Note – in July 2015, the UKCG and NSCC (National Specialist Contractor’s Council) merged to form Build UK. A list of the members of the new body can be found here

Invasive Species “Control Order” Proposals

At present in England and Wales, whilst it is a criminal offence to “cause to spread” invasive non-native species such as Japanese knotweed, there are no real controls on allowing to continue growing on your land if you already have it, However authorities in Scotland have for some time been able to apply “Control Orders” to existing infestations, and as a result of new European pressure, the Law Commission reviewed the Scottish approach during 2014, and made recommendations for the introduction of essentially similar legislation in England

The 74 page report makes 45 separate recommendations, starting from a recommendation that “there should be a power to make species control orders to control invasive non-native species in England and Wales modelled broadly on the procedure introduced by the Wildlife and Natural Environment (Scotland) Act 2011.”

In taking this approach, the Law Comission recommends that species that could be controlled by such an order should be BOTH:

  • Invasive – if not controlled would have an adverse effect on biodiversity, other environmental interests, or social or economic interests, AND
  • either an animal or plant not ordinarily resident in or a regular visitor to Great Britain, or one listed in Schedule 9 of WACA 1981

For such species, the recommended process would follow four distinct steps:

  1. Investigation – recommendations include powers to permit regulators to enter land (but not buildings) to establish whether or not a species is present that meets the tests above.
  2. Species Control Agreement – a voluntary agreement between the regulator and the landowner / occupier to carry out works to control or eradicate invasive non-native species. If an agreement is put into place and the works are carried out, the process would stop at this point.
  3. Species Control Order – a requirement for the landowner / occupier to carry out specific works to control or eradicate invasive non-native species.
  4. Enforcement – Should the works agreed in a Control Agreement or specifies in a Control Order not be carried out, the authority can carry out the works themselves, or arrange for them to be carried out.

The are also provisions for omitting the first two steps in emergency situations. However, some of the more interesting recommendations are tucked away within the report, including the recommendation that the cost of control or eradication should be borne by the public purse, except in instances where the situation has been made worse by wilful action or neglect by the landowner / occupier. Similarly, any proposed control actions should be proportional to the wider risk posed should the species remain unchecked on that site.

Overall, in the case of invasive plant species, I could see this being primarily used where infestations are spreading across boundaries, or in instances where plants have been spread through neglect of proper procedures. It will be interesting the see the final form of the legislation once implemented.

Japanese Knotweed ID – Autumn

Knotweed ID AutumnKey features:

  • Mature clumps 2-3 metres high, with dense stands of yellowing bamboo-like stems up to 20-25mm diameter which gradually turn brown and dry as colder weather sets in.
  • Distinctive masses of bare flowering spikes in clusters from nodes towards the ends of branching zig-zag stems.
  • Where leaves are still present, a single shield-shaped leaf 10-12cm long with a flat base from each node.

Similar non-invasive species:

  • Hazel – looks very similar in autumn at first glance but leaves are much more heavily veined and ribbed, stems are straight rather than zig-zag, and have no flower spike remnants at ends.

More information:

WACA 1981 Schedule 9 Plant List Update

The two terrestrial plants that have been on Part II of Schedule 9 of the Wildlife & Countryside Act since it’s introduction in 1981 – Japanese Knotweed and Giant Hogweed – are now quite well known, recognized and properly controlled on construction sites. However, on 6th April 2010, a major update of Schedule 9 came into effect, adding a great many new plants to Schedule 9, many of which are relatively well known as common garden or ornamental pond plants.

My consolidated list of Schedule 9 plants (England &  Wales) with the four original (1981) plants highlighted in bold now looks like:

Terrestrial Plants:

  • Allium paradoxum (Few-flowered Leek), A. triquetrum (Three-cornered Garlic)
  • Carpobrotus edulis (Hottentot Fig)
  • Cotoneaster bullatus (Hollyberry Cotoneaster), C. horizontalis (Cotoneaster), C. integrifolius (Entire-leaved Cotoneaster), C. microphyllus (Small-leaved Cotoneaster), C. simonsii (Himalayan Cotoneaster)
  • Crocosmia x crocosmiiflora (Montbretia)
  • Disphyma crassifolium (Purple Dewplant)
  • Fallopia japonica (Japanese Knotweed), F. japonica x F. sachalinensis (Hybrid Knotweed), F. sachalinensis (Giant Knotweed)
  • Gunnera tinctoria (Giant Rhubarb)
  • Heracleum mantegazzianum (Giant Hogweed)
  • Impatiens glandulifolius (Himalayan Balsam)
  • Lamiastrum galeobdolon subs argentatum (Variagated Yellow Archangel)
  • Parthenocissus inserta (False Virginia Creeper), P. quinquefolia (Virginia  Creeper)
  • Rhododendron luteum (Yellow Azalea), R. ponticum (Rhododendron), R. ponticum x R. maximum (Rhododendron)
  • Rosa rugosa (Japanese Rose)

Aquatic Plants

  • Azolla filiculooides (Water Fern)
  • Cabomba caroliniana (Fanwort, aka Carolina Water-Shield)
  • Crassula helmsii (Australian Swamp Stonecrop, aka New Zealand Pygmyweed)
  • Eichhornia crassipes (Water Hyacinth)
  • Elodea spp (All Waterweeds)
  • Grateloupia luxurians (Red Algae)
  • Hydrocotyle ranunculoides (Floating Pennywort)
  • Lagarosiphon major (Curly Waterweed)
  • Ludwigia grandiflora (Water Primrose), L. peploides (Floating Water Primrose), L. uruguayensis (Water Primrose)
  • Myriophyllum aquaticum (Parrot’s Feather)
  • Pistia stratoites (Water Lettuce)
  • Sagittaria latifolia (Duck Potato)
  • Salvinia molesta (Giant Salvinia)

Marine Plants

  • Codium fragile (Green Seafingers)
  • Macrocystis pyrifera (Giant Kelp)
  • Sargassum muticum (Japanese Seaweed)

As has been the case with Japanese Knotweed and Giant Hogweed for the past 30 years, it is now a Section 14 offence to cause any of these plants to grow in the wild, and this includes inadvertently spreading plant material during construction operations. Any soil or plant waste containing viable growing material from any of the above plants is classed as “controlled waste” under the Waste Duty of Care, and must be dealt with as such.

I now cover invasive plants as part of my Wildlife & Biodiversity Masterclass. Please contact me if you would like more details of this course.

Japanese Knotweed

Japanese Knotweed (Fallopia japonica) is a fast growing perennial plant that has no native predators in the UK, and can regenerate from tiny fragments of material (0.7 grammes in the case of roots). Since its introduction as a “must have” plant on Victorian estates in the mid-nineteenth century (it thrived anywhere, including poor ground), it has become a serious nuisance in the wild, displacing native plants and their associated wildlife. Due to its deep-rooted nature (up to 7m horizontally from the crowns and 4m deep) its is very difficult to completely excavate or kill with herbicide, and unless comprehensively treated, will soon recover and resume being a problem.

Its frequent presence on development sites, resistance to quick eradication, wide root spread, and ability to regenerate from tiny fragments makes it a unique challenge that if not dealt with properly, opens both contractors and developers to the risk of prosecution. If you have time (at least a year) its always better to eradicate Knotweed on site before you start work.

The Legal Position

Japanese Knotweed is one of over 40 plants listed in Schedule 9 Part II of the Wildlife & Countryside Act 1989, which makes it a Section 14(2)(a) offence to “plant or otherwise cause (Japanese Knotweed) to grow in the wild”. The penalties for a Section 14 offence were modified by the Countryside & Rights of Way Act 2000, and a magistrates’ court can now impose a fine of up to £5000 on conviction, a six month prison sentence, or both.

The legislation applies to both deliberate and accidental spreading, and sites contaminated with Japanese Knotweed need to be carefully controlled to avoid breaches and potential Regulatory action. (This includes disposal of Knotweed waste at a site not licensed to receive it.) However, it should be noted that the legislation applies to “spreading” – it is not currently illegal to have Japanese Knotweed growing on your land providing you don’t spread it into the wild and it doesn’t cause a nuisance to neighbours (although the latter is a civil liability rather than criminal offence).

Dealing with Japanese Knotweed

The Environment Agency has produced a Knotweed Code of Practice which sets out the actions expected of Developers and Contractors when dealing with Japanese Knotweed on site.

Disposing of Japanese Knotweed, and soil contaminated with Japanese Knotweed roots

Due to its ability to regenerate from tiny fragments of viable material after a dormancy of up to 20 years, soil and waste containing Japanese Knotweed is considered to have the potential to cause “ecological harm”, and as such is considered to be a Controlled or Directive waste under the Waste Management Licensing Regulations 1984. As such, the producers of Knotweed waste have obligations for its proper treatment under the Waste Duty of Care, including ensuring that it is only disposed of at a site which has an appropriate permit to receive it. (Note – as the material has to be buried at a depth of 5m or more, not all “non-hazardous” sites are able to receive it – permits should be carefully checked.)

With regard to the description of the waste on the Waste Transfer Note (WTN), the Environment Agency have previously advised that the materials for disposal should be segregated on site and the following LOW Regs 2005 codes used with the bold additions to the descriptions clearly stated on the WTN:

  • Japanese Knotweed vegetation – 20 02 01 “Biodegradable waste containing Japanese Knotweed
  • Soils contaminated with Japanese Knotweed roots – 17 05 04 “Soils and stones other than those mentioned in 17 05 03* containing Japanese Knotweed

Do you suspect you have Japanese Knotweed on your site? – Give me a call! Looking for a training course on Invasive Plants? – Check out my Wildlife & Biodiversity Masterclass