Managing Japanese knotweed - Can we do even better?

We reported last week in our blog ‘Japanese knotweed Management Overseas – Defra Report’ on Defra’s independently commissioned report “Management of Japanese knotweed Overseas”. The clear message was that the UK’s approach to knotweed was essentially justified (it really is a uniquely difficult and environmentally damaging weed) and proportionate.

However, the reporting team, at Defra’s request, also tackled questions about potential areas for change and improvement during property sales. As promised, we are going to be looking at these in a bit more detail. Simply keep on reading to find out more!

How could the approach be improved in the four UK administrations?

Large parts of the report explain all the many ways in which Japanese knotweed is relevant to a house sale or property development. But the report suggests that vendors and buyers should be supplied with the TA6 Guidance Notes (Property Information Form) during the conveyancing process, given access to ‘best practice’ guidance regarding management measures and that site-specific risk assessments by trained professionals should be promoted by Government etc.

What the PCA says:

From a PCA perspective, we could not agree more! The Law Society’s TA6 form Guidance Notes are essential so vendors can consider whether knotweed is present and whether it has been present in the past and/or may arise in the future (e.g. due to ‘managed’ but dormant knotweed rhizomes present in the soil on their land or within 3m), all of which will reduce the number of cases of litigation arising post-sale!

Best practice’ is a product of experience and knowledge and our PCA members have demonstrated both. They are regularly audited to ensure they adopt new research findings as they arise, whilst always complying with strict regulations regarding the use of herbicides (including Integrated Weed Management).

The Royal Institution of Chartered Surveyors (RICS) Risk Assessment framework is included in PCA member survey reports but we recognise the need to develop a more sophisticated approach, which results in Japanese knotweed being managed in an optimal and appropriate way (specific to the site and the owners priorities). We are working closely with RICS and academic institutes to develop these new tools for surveyors.

Can we manage ‘perceptions’ about Japanese knotweed

The report goes on to applaud the effectiveness of the UK’s approach to knotweed management, but is concerned about the language used by some professionals which can lead to a bias in perception regarding the potential impact of Japanese knotweed on property. The recommendation is that the threat of Japanese knotweed should be focussed on its environmental rather than physical impact.

What the PCA says:

In our Codes and Guidance documents we have always stated that Japanese knotweed is capable of causing structural impacts on and around buildings and any internet search will reveal photographic evidence of undeniable cases.

However, our members know (and research has shown) that in most cases the impact of knotweed depends on the age/maturity of the plant and the original condition of the building (knotweed exploits existing weaknesses), and that the ‘worst’ examples are usually in new build projects through mistakes such as failing to remove knotweed rhizomes before building.

However, it is too simplistic to say we should not highlight these impacts in the context of property sales. Amenity areas and paved/hard surfaces are all ‘at risk’ of being colonised and damaged by an unmanaged knotweed infestation.

The press is another matter of course! But perhaps we can all do our bit to manage the way journalists tell their stories. Yes, it is ‘news’ when someone has their garden taken over by their neighbour’s knotweed but completely wrong that they should suggest that the same knotweed is likely to make their house fall down! We can all agree that the environmental hazards associated with Japanese knotweed and many other invasive species should (and indeed do already) form part of the overall ‘risk’ profile presented to the client but only as part of a balanced overview.

We support the suggestion by the report’s authors that there should be a public education and awareness-raising campaign to address the stigma of Knotweed and reassure potential house buyers/sellers that the implementation of professional management plans for Japanese knotweed provides appropriate mitigation.

Lenders have different policies regarding Japanese knotweed – is it really a surprise?

The report has a slight problem with a lack of coherence amongst lenders regarding the latent liabilities/risks associated with Japanese knotweed, but acknowledges that this may change when the RICS update their Risk Assessment Framework (see above). But, to be honest, we would be surprised if the situation was any different and it may well remain the case in the future.

The provision of mortgages is a competitive market and all lenders have their own processes for assessing risk which are multi-faceted. We may be focused on knotweed here but banks and building societies consider a large matrix of risk factors, not least of which are simple matters such as loan-to-value ratios etc. Of course, lenders are constantly evaluating/re-evaluating their policies and Japanese knotweed will always be relevant to them.

Perhaps we too can hope that there is more uniformity in approach as this would undoubtably lead to clarity in the property market. But “don’t hold your breath”!

Can training and education help property professionals avoid litigation?

A potential purchaser of a property will rely on many ‘professionals’ to guide them through the process; lenders, valuers, conveyancers and estate agents. But none of these are experts in the detection and reporting of knotweed nor indeed can explain to their client all the risk factors that the knotweed presents in each individual case.

The report’s authors encourage a programme to raise knowledge and awareness in all these professions with the ultimate aim of reducing the number of ‘missed’ infestations and thereby reduce the number of cases of litigation. Also, to promote the resolution of disputes through mitigation without recourse to the law.

What the PCA says:

At the PCA, we have a core mission in our articles of Association to ‘educate and inform’ and have developed a significant capability to deliver training in the specialist subject areas we represent. Not only would we encourage any property professionals to contact us about sector-specific training tailored to their needs, but we are also close to publishing a Guidance Note specifically aimed at valuation surveyors – watch this space!

Sustainability – just a word? Or something we can really deliver?

There are two sides to the report’s concerns about sustainability. One is that we can do a reasonable job getting on top of Japanese knotweed in the residential sector, but only if there is a collaborative approach between neighbours! Neither they nor we at the PCA are sure how this can be delivered but it is a good point well made.

Firstly, managing one-half of a Japanese knotweed stand is not likely to be effective for long (nor is it sustainable) and secondly, if the client needs assurance (without the co-operation of their neighbours) the overall cost of the management plan increases significantly and may involve extensive soil removal.

The second side to this is that in a great many cases Japanese knotweed can be managed effectively with a herbicide treatment programme, but these rely almost entirely on glyphosate.

This herbicide is alone amongst its peers in that it has the ability to kill a perennial plant like Japanese knotweed, but slowly, so that the plant moves the active ingredient to its extensive root/rhizome system before the herbicide acts to prevent further growth. There is therefore a threat to the sustainability of the current knotweed management approach if glyphosate is banned or significantly restricted in use.

Bottomline of the report!

The report calls on all stakeholders in the sector to do two things: one, to use an ‘evidence—based approach to herbicide treatment programmes and two, to ensure that appropriately qualified and accredited contractors are sought for the control, management and remediation of knotweed.

We could not have put it better ourselves! More next week on the two other key questions (scope for improvements) addressed by the report’s authors…

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