Thames Landscape Strategy - Hampton to Kew -

Arcadian Diary March 2006

During the past three months volunteers have been very busy making the most magnificent ‘dead hedge’ in front of Ham House. We have been lucky enough to have volunteers from local schools, London’s Arcadia, the Ham and Petersham Association, BTCV, The Environment Trust for Richmond and the National Trust to help us. Dead hedging is a traditional method of creating a hedge which dates back centuries and creates an instant and thick boundary interwoven with live plants such as holly and thorn.

The hedge has been made as part of the Thames Landscape Strategy’s management plan for the towpath and construction has been managed by the London’s Arcadia Heritage Lottery Fund scheme. Good conservation practice inevitably involves the periodic management of scrubland areas as shrubs age and new growth is required. It was agreed that the area in front of Ham House was way overdue for some work. Overgrown scrub was cleared before the bird nesting season started and the decaying wood and branches used to construct the hedge. Most of the mature trees were retained whilst many new species are being planted including thorns, holly, dog roses and elder. These will quickly grow to provide a valuable mixed hedgerow habitat along the river.

Rotting and decaying dead wood is actually one of the best habitats for biodiversity as it can support a range of different species including 1,800 invertebrate species, beetles, hoverflies, birds, bats, lichens, mammals, fungi and non-biting midges (that themselves are an important food source for bats). For this reason it is important to leave fallen or coppiced branches intact on the ground as close to the parent tree as possible. We try to do this in all our project work although it can be quite difficult in areas that are mown and along a tidal river. Managing this sort of environment is different from other locations such as Richmond Park. Here fallen branches can be left in situ, however, along the riverbank it often needs to be moved. The power of the tides is quite staggering and can lift even the largest fallen tree. Once in the flow these can be transported long distances and can damage anything that it brushes against and potentially take out a boat. For this reason we move wood from vulnerable areas to a safer position. We choose locations as close to the original site as possible out of the reach of the tides.

The wood is stacked to create piles or it is partially buried in the ground. The end result is called a (stag beetle) loggery. This work is mainly carried out by volunteers and provides the most wonderful home for stag beetle larvae to grow. Whilst out walking you may come across one of these usually in the corner of a wood or behind a towpath hedge. At first glance they look just like a pile of logs ready to be chopped for the fire. In fact we often get phone calls asking why we haven’t cleaned up after work has taken place. For this reason we try to choose discreet places to make the piles away from the main footpath or sight lines. A range of sites are chosen to maximise biodiversity as different species like different habitats. These include shaded, partially lit, full sunshine and even submerged under water.

‘Biodiversity’ is a word that we often use but it is also a word that I know is confusing to many people as it has so many different meanings. The word was first coined in the US in the mid 1980’s and is used to describe the variety of plants, animals and micro-organisms that inhabit a place and how each of these interact with each other.

Biodiversity can be achieved through a variety of different measures ranging from large habitat creations such as at the Wetlands Centre in Barnes to the planting of a short hedge or creating a pond in a back garden – it is something that most people can help achieve. One of the trickiest decisions to make however, is what habitat to sustain where – as inevitably to manage one type is often at the expense of another. For this reason ‘Biodiversity Action Plans’ have been produced for the Tidal Thames and for each borough across London. To accompany these a series of ‘Habitat and Species Action Plans’ have been developed that concentrate on and prioritise those habitats and species which are rare, in decline or characteristic of the local area. These set priorities and ensure that biodiversity priorities can be weaved into wider management objectives.

This way of working is true in another area of the Thames Landscape Strategy’s work – garden restoration. Along our Arcadian Thames between Hampton and Kew we have more conservation areas, listed buildings and registered historic parks and gardens than anywhere else in the country. Garden enthusiasts can visit almost every age of English garden from the Tudors to the present age. This is quite unique. Many of these gardens are decayed and are in the process of restoration. This is not as easy as it may sound. A garden is a constantly changing place and modern priorities are often quite different to those that were around when the garden was created. I am quite certain that loggeries and accessible wheelchair ramps did not originally form part of a Victorian park but in restoration today they are an essential part of the proposal. For this reason the level of ‘restoration’ varies: Some gardens are so important that they are restored as close to the original as possible such as the Privy Garden at Hampton Court Palace. Other gardens are restored more in the spirit of the original, taking account of modern needs and biodiversity.

A lot of our restoration work (both garden and natural environment) takes place over the winter months to avoid the bird nesting season. However there is some work that can only take place when the weather is warmer. In April, as it finally warms up we can start sowing grass seed to the Terrace Field on Richmond Hill and laying the final pieces of turf along Choldmondely Walk. We will also be able to finish off many of the works that we started last year which have been impossible to complete over the winter due to damaging frost action. This includes the top sealed gravel surface to footpaths including the new paths down Richmond Hill.

The weather and climate affect the type of work we can carry out and when in the short term but increasingly we are beginning to plan for much more long-term changes in our weather caused by climate change. All scientists across the globe are now agreed that the climate is changing but as yet it is not agreed as to what is causing the change and what the impact will be.

We should expect warmer summers with lower rainfall and more droughts. Yet at the same time it is the predicted that intense periods of rainfall and wetter winters will cause damaging floods and sewage overflow. It is predicted that climate change will have a damaging effect on river use and vulnerable heritage attractions (such as Hampton Court and Kew), whilst hotter summers will actually increase the number of visitors who want to visit these places. Habitats are likely to change, bird migrations disrupted and stress on trees and plants will increase.

It is now accepted that many of our wonderful parks and gardens will have to evolve and adapt to climate change but exactly how is still unclear. In the meantime we will continue to manage these wonderful places as best as we can and take into account any predicted changes to our climate.

RIVERFACT
As April approaches it is finally getting warmer following a long cold winter. This said, it is hard to believe but last year was actually the warmest year ever recorded for the northern hemisphere with average temperatures 0.65 degrees above the long term average. In the UK, the temperature was 1.07 degrees above average making 2005 one of the warmest ten years on record.

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