California Redwoods Growing in Britain

Collated notes by Edward Brun 

History

Sequoia sempervirens was introduced into England in 1843 by Knight and Perry in the form of plants from Russia.

A confirmation appeared as a ‘news story’ not long ago when American botanists were surprised to find old redwood plantations in the Crimea. It is, indeed, often not realised that the Russians made an early attempt to colonise parts of California. One party settled not far north of San Francisco, at Fort Ross on the Sonoma coast of California. They left in the early winter of 1841 after 29 years of occupation. At least one considerable collection of botanical specimens from this source remained at Leningrad unexamined until the 1930s when it was sent to the U.S.A. for determination. It was made during the last year before they left and though plants found growing in the redwood groves were included, there was surprisingly no specimen of Sequoia sempervirens. The collection was sent to Leningrad via Alaska and Siberia. (Howell, 1937)

It is interesting to note that the great grandson of John Naylor, says he brought from America (in pots, it is said) the Sequoia sempervirens seedlings which now form the famous Redwood Grove at Leighton, in 1862, but a earlier article by Miles Hadfield in the RFS journals claims that they were planted in 1856.

About the tree

It is a tree which requires a favourable site if it is to thrive, and will stand partial shade. It dislikes exposed sites and very acid soils. It is sensitive to frost and anybody wishing to consider the use of this species on a large scale would be well advised to consult the relevant specialists in the Forestry Commission Research Agency.

Longleat

There are impressive stands of Sequoia sempervirens at Longleat. They have 126 acres of the species growing there, which is the largest area outside the USA, and has resulted in the election of the estate to the membership of the Redwood Association.

John McHardy, former head forester at Longleat, was convinced it could be profitable if sufficient quantities of its timber could be made available. It dries rapidly, takes creosote well and makes good weatherboarding. Its strength improves on drying, and in America the heartwood from old growth is very durable and is widely used as a structural timber. At Longleat some trees have originated from cuttings raised in sand beds on the estate and the best of the coppice regrowth has been singled to create a second generation.

Brechfa Forest Plots Results after 40 Years

This site is about 14 miles west of Llandovery in Carmarthenshire. The plots are located at elevations of between 200 and 250m above sea level and climate is very favourable to tree growth, with a mean annual rainfall of 1,700mm.

Sequoia sempervirens is growing at rates in excess of that expected from Sitka spruce in this area with a General Yield Class at Brechfa of 30 which compares to 20-30 in other published Welsh or British data

Results from sample plots are as follows:

redwoods-table.jpg

 

A Natural Regeneration Experience

For many years, it has been assumed that fertile seeding in Britain is unlikely. This may be due to the fact that the male flowers are subject to winter frost damage: pollen is normally shed in February. MacDonald et al (1957) states that natural regeneration by seed is highly unlikely. However, there are occasional reports of natural regeneration but only ever at low levels.

On the Cliveden Estate Sequoia sempervirens were blown over during the storm of 25 January 1990. More than 18 months passed before the “Pheasantry” was cleared of its windblown trees. Several S. sempervirens were uprooted in various sections of this wood. In August 1991, whilst clearing two such trees, large numbers of one-year-old S. sempervirens seedlings were noticed. The heaviest regeneration occurred where there was little leaf litter. The seed is extremely small, so to survive it must get its roots into mineral soil as soon as possible.

There are few records of natural regeneration of S. sempervirens in Great Britain. So why has this occurred in substantial numbers on the Cliveden Estate? It could be that these 90-year-old trees are producing increased fertile seed at this stage of their development. The extra light given to the crowns of the ‘mother’ tree and to the ground – helped by the previous storm of October 1987 – may have helped the production of viable seed. It would appear that ideal conditions for natural regeneration were achieved by accident ! Which is often the case in forestry. 
 

Some notes from Patrick Hills, Camphill Estate, Tonbridge

My father first planted S. sempervirens in 1956 with a dozen or so and then many more in 1958. Thinning should be “little and often”.

Though they seem to put up with exposure, redwoods far prefer shelter – especially side shelter. They dislike hot roots and hot sun for a couple of years, so we use small plants (1 + 1) inside a tree shelter – not less that 4'' diameter and cut down to 12''-15''. We add a netting sleeve roughly 12'' diameter x 30''/36'' high. The shelters come off after one or two seasons.

Redwoods seem to endure minor frosts but dislike cold drying winds from the northeast. If planted at wide spacing, a lot of staking and propping up will be necessary in the first five years. Ideally, final spacing should be at 25 feet between stems. In practice, I have plenty at 20ft or less and some at 30ft or more.

We have one specimen which is free grown and in full exposure on the edge of Grinstead clay with Tunbridge Wells sandstone. It is 30'' BHQG with a heavy taper and without a blemish in the first 30ft. If I find a stem of 25''-30'' QG at breast height and I am looking for a log to convert, then soon after I have knocked it down, coppice shoots emerge and neighbouring stems respond quickly to more room.

It is nice to leave a pile of logs in the round in a wood with the bark on, in a shady place. The logs will dry out very little and we do not even attempt to paint the ends. They do not seem to rot and the species has an amazing record of surviving in the round.

I am sorry about all the vagueness but I have not forgotten about pruning. That is absolutely essential – pruning, pruning, pruning! 
 

Sennowe Park, Norfolk

Tom Cook has two fine stands which he showed to Royal Forestry Society members in 2002. These were planted in 1964 and are situated in two small valleys. Some trees have achieved a top height of over 100ft already ! 
 

The Leighton Redwoods, Welshpool

Generally acknowledged to be the finest and oldest Redwood Grove in the country, these trees were planted in 1856 and survive today with younger speciments around them. The Royal Forestry Society were gifted this magnificent grove by the Naylor family and skillfully manage it under the care of David Williams.

Despite the lack of Californian sun and coastal fog, the trees have prospered – thanks to over one metre of rainfall per annum. Heights in excess of 40m and average tree volumes of 20m3, make them an aweinspiring sight.

References:
RFS Journal 1998 Vol 92 no. 2 – The Brechfa Forest Plots: Results After 40 Years by Neville Danby and Bill Mason
RFS Journal 1998 Vol 92 no. 3 – Natural Regeneration of Sequoia Sempervirens at the Cliveden Estate, Buckinghamshire by Derek Paxton
RFS Journal 1988 Vol 82 no. 1 – Correspondence “A Family’s Connection with Forestry” – T. Peter Naylor
RFS Journal – Whole Society visit to Wessex – 1989, Longleat (Thursday 11 May)
RFS Journal 1964 Vol 58 no. 4 – The Redwood in Britain by Miles Hadfield.
 

Editors Note: We have had a request from ARWYN MORGAN of AOM and Associates in Wales to ask our members for information on groves or small plantations of Wellingtonia or California Redwood, so that he can research their growth characteristics. The utilisation of their timber is also part of his work.

Arwyn Morgan – AOM & Associates
A Garnbwll
Myndcerrig
Pontyberem
LLANELLI
Camarthensire SA15 5BN
Tel: 01269 870031
email: aomassc@hotmail.com