The Radial Growth-Rate of Yews (Taxus Baccata) at Hampton Court, Middlesex

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<ul><li><p>The Garden History Society</p><p>The Radial Growth-Rate of Yews (Taxus Baccata) at Hampton Court, MiddlesexAuthor(s): Donald PigottSource: Garden History, Vol. 23, No. 2 (Winter, 1995), pp. 249-252Published by: The Garden History SocietyStable URL: http://www.jstor.org/stable/1587082 .Accessed: 31/07/2013 07:31</p><p>Your use of the JSTOR archive indicates your acceptance of the Terms &amp; Conditions of Use, available at .http://www.jstor.org/page/info/about/policies/terms.jsp</p><p> .</p><p>JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range ofcontent in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new formsof scholarship. For more information about JSTOR, please contact support@jstor.org.</p><p> .</p><p>The Garden History Society is collaborating with JSTOR to digitize, preserve and extend access to GardenHistory.</p><p>http://www.jstor.org </p><p>This content downloaded from 160.94.45.157 on Wed, 31 Jul 2013 07:31:50 AMAll use subject to JSTOR Terms and Conditions</p></li><li><p>It only remains to say that the original purpose, to establish a family link to George London, has not yet been achieved. A direct line looks unlikely, though still just possible through John, the younger son, who has so far eluded efforts to pinpoint his later identity. It would, of course, be something of a disappointment if our family 'legend' had eman- ated from The Lodge at Woodcote only in the early years of this century. </p><p>It only remains to say that the original purpose, to establish a family link to George London, has not yet been achieved. A direct line looks unlikely, though still just possible through John, the younger son, who has so far eluded efforts to pinpoint his later identity. It would, of course, be something of a disappointment if our family 'legend' had eman- ated from The Lodge at Woodcote only in the early years of this century. </p><p>According to the documentary evidence, John Rose was the great uncle of Rebecca Walkes, and therefore the great great uncle of her son George London junior. However, it can be plausibly argued that the latter merely perpetuated the relationship used by his family circle when he was growing-up. Thus we have an entirely credible identity for the pineapple presenter. Walpole got it right; so was the fruit home-grown after all, even at such an early date, rather than imported as some suggest? </p><p>According to the documentary evidence, John Rose was the great uncle of Rebecca Walkes, and therefore the great great uncle of her son George London junior. However, it can be plausibly argued that the latter merely perpetuated the relationship used by his family circle when he was growing-up. Thus we have an entirely credible identity for the pineapple presenter. Walpole got it right; so was the fruit home-grown after all, even at such an early date, rather than imported as some suggest? </p><p>ACKNOWLEDGEMENT Grateful acknowledgement is made of the valuable help, encouragement and advice freely given by Mr Alastair Laing, Adviser on Pictures and Sculpture </p><p>ACKNOWLEDGEMENT Grateful acknowledgement is made of the valuable help, encouragement and advice freely given by Mr Alastair Laing, Adviser on Pictures and Sculpture </p><p>REFERENCES I. David B. Green, Gardener to Queen Anne: </p><p>Henry Wise and the Formal Garden (OUP I956). 2. Baptised 4 Sept. 1653, probably at </p><p>St Alphage, Greenwich, son of another Henry Wise. (International Genealogical Index for Kent). </p><p>3. Public Record Office Ref: PROB II/538. </p><p>REFERENCES I. David B. Green, Gardener to Queen Anne: </p><p>Henry Wise and the Formal Garden (OUP I956). 2. Baptised 4 Sept. 1653, probably at </p><p>St Alphage, Greenwich, son of another Henry Wise. (International Genealogical Index for Kent). </p><p>3. Public Record Office Ref: PROB II/538. </p><p>to the National Trust. It is hoped that this account may contribute towards the final resolution of the mystery painting. </p><p>to the National Trust. It is hoped that this account may contribute towards the final resolution of the mystery painting. </p><p>4. PRO Ref: PROB 11/960. 5. John Harvey, Early Nurserymen (I974), </p><p>caption to plate I. 6. PRO Ref: PROB II/354. 7. Court of the Archdeacon of Sarum, 21 Nov. </p><p>1638, Wiltshire Record Office, Trowbridge. </p><p>4. PRO Ref: PROB 11/960. 5. John Harvey, Early Nurserymen (I974), </p><p>caption to plate I. 6. PRO Ref: PROB II/354. 7. Court of the Archdeacon of Sarum, 21 Nov. </p><p>1638, Wiltshire Record Office, Trowbridge. GEORGE ROYLE </p><p>22 Church Walk, Melksham, </p><p>Wiltshire SNI2 6L Y </p><p>THE RADIAL GROWTH-RATE OF YEWS (TAXUS BACCATA) AT HAMPTON COURT, </p><p>GEORGE ROYLE 22 Church Walk, </p><p>Melksham, Wiltshire SNI2 6L Y </p><p>THE RADIAL GROWTH-RATE OF YEWS (TAXUS BACCATA) AT HAMPTON COURT, MIDDLESEX The age and diameter of the trunks of 24 trees of English yew (Taxus baccata) from the site of the Privy Garden at Hampton Court Palace, Middlesex, England, have been measured. The relationship between diameter (cm) and age (years) is adequately described (r=o.9278) by a linear regression y (diameter) = 4.09 + 0.263 x (age). The mean rate of radial increment of 1.32 mm year-l is similar to measurements made in Ger- many but significantly less than many previously published estimates. The distribution of knots within the trunks of the original trees confirms that they were clipped into cones before being allowed to grow freely. </p><p>INTRODUCTION </p><p>Although the age of yew trees (Taxus baccata L.) has long attracted attention and has been the subject of much speculation, most of the published information on the radial growth-rate of the species, which is actually based on counts of annual rings, dates from the last century (De Candolle I832, Bowman I837, Rose 1864, Henslow I889, Lowe I891, Lowe I897, Kirchner, Loew &amp; Schroter I908) and is largely derived from single or very few trees at any one site. </p><p>The removal of the yews, following the decision to restore the Privy Garden of William and </p><p>MIDDLESEX The age and diameter of the trunks of 24 trees of English yew (Taxus baccata) from the site of the Privy Garden at Hampton Court Palace, Middlesex, England, have been measured. The relationship between diameter (cm) and age (years) is adequately described (r=o.9278) by a linear regression y (diameter) = 4.09 + 0.263 x (age). The mean rate of radial increment of 1.32 mm year-l is similar to measurements made in Ger- many but significantly less than many previously published estimates. The distribution of knots within the trunks of the original trees confirms that they were clipped into cones before being allowed to grow freely. </p><p>INTRODUCTION </p><p>Although the age of yew trees (Taxus baccata L.) has long attracted attention and has been the subject of much speculation, most of the published information on the radial growth-rate of the species, which is actually based on counts of annual rings, dates from the last century (De Candolle I832, Bowman I837, Rose 1864, Henslow I889, Lowe I891, Lowe I897, Kirchner, Loew &amp; Schroter I908) and is largely derived from single or very few trees at any one site. </p><p>The removal of the yews, following the decision to restore the Privy Garden of William and </p><p>Mary at Hampton Court Palace in Middlesex, made available not only stems of the original trees planted in I703-04, but also a range of younger trees which were later plantings. Measurements of these stems and counts of rings on complete sections have allowed the growth-rate to be estab- lished for trees grown in these conditions. </p><p>MATERIALS AND METHODS Transverse sections of the trunks, 200-250 mm thick, were cut from 24 yews with a chain-saw above the level at which the main roots converge but within 0.5 m of the ground. </p><p>A band Ioo-I50 mm wide was planed and finely sanded along the longest radius or, if this was partly decayed, the band was displaced tangentially to the nearest undecayed part. </p><p>The wood of yew is compact and without resin canals. The annual rings are clearly defined by the differences in thickness and, in the heart-wood, of colour of the walls of the tracheids of the early and late wood. The rings were counted moist at x o1 magnification. Some of the trunks showed periods of very slow radial growth to give as many as 36 rings in o1 mm in the most extreme case. Several counts could only be made by counting short lengths of a radius and then, because of cracks, knots or patches of decay, moving tangentially </p><p>Mary at Hampton Court Palace in Middlesex, made available not only stems of the original trees planted in I703-04, but also a range of younger trees which were later plantings. Measurements of these stems and counts of rings on complete sections have allowed the growth-rate to be estab- lished for trees grown in these conditions. </p><p>MATERIALS AND METHODS Transverse sections of the trunks, 200-250 mm thick, were cut from 24 yews with a chain-saw above the level at which the main roots converge but within 0.5 m of the ground. </p><p>A band Ioo-I50 mm wide was planed and finely sanded along the longest radius or, if this was partly decayed, the band was displaced tangentially to the nearest undecayed part. </p><p>The wood of yew is compact and without resin canals. The annual rings are clearly defined by the differences in thickness and, in the heart-wood, of colour of the walls of the tracheids of the early and late wood. The rings were counted moist at x o1 magnification. Some of the trunks showed periods of very slow radial growth to give as many as 36 rings in o1 mm in the most extreme case. Several counts could only be made by counting short lengths of a radius and then, because of cracks, knots or patches of decay, moving tangentially </p><p>NOTES NOTES 249 249 </p><p>This content downloaded from 160.94.45.157 on Wed, 31 Jul 2013 07:31:50 AMAll use subject to JSTOR Terms and Conditions</p></li><li><p>GARDEN HISTORY 23:2 </p><p>y = 4.09 + 0.263 x </p><p>100 </p><p>u - 80 S O </p><p>61 , 60 </p><p>.c 40 rQ </p><p>.* </p><p>. </p><p>0 </p><p>20 </p><p>0 200 300 </p><p>Age of tree (years) </p><p>Figure i. The relation between the diameter of the trunk at 0.5 m above the ground and the age determined by counts of annual rings </p><p>of yews from the Privy Garden at Hampton Court </p><p>round a well-defined ring until another radius could be followed. </p><p>The diameter for the whole section was calcu- lated simply by measuring the circumference and dividing by 3.142. The measurement is at a level below the normal breast height of 1.3 m but yew trunks are often cylindrical or expand upwards. </p><p>Radial longitudinal sections of the trunks were also cut. A map was made of one face of each section using a square grid to record the distribution of all knots and buried branches. </p><p>RESULTS </p><p>The age was determined by ring-counts of all but one of the 24 slices. One was extensively decayed in the central part. All the sections proved to be of single trunks although some had more than one centre and fusion had occurred very early in the life of the tree. None of the trunks was formed by fusion at a late stage. </p><p>Thirteen of the trees had been planted about the end of the sixteenth century and were therefore the original trees. In several of these the stem of the tree which had been planted could be identified by normally having seven broad rings, followed by two very narrow rings, presumably caused by reduction in growth during recovery of the root-system fol- lowing transplanting. This feature allows the actual year of planting to be identified as 1703-04. This is two years after the garden was laid out, according to documentary evidence. A few trees had a more complicated structure in the centre and appear to have been planted earlier, possibly in tubs or </p><p>elsewhere in the garden, and then transplanted again into the Privy Garden. </p><p>In Figure I the mean diameter of the tree is plotted as ordinate against age as abscissa. A linear regression y=4.09+0.263x, where y is the dia- meter in cm and x the age in years, gives a satisfac- tory fit to the data (r = 0.9278) and provides a mean value for the radial growth-rate of 1.32 mm year- 1 </p><p>The basis of this technique is as follows. As a tree grows older, so its trunk increases in diameter. If the diameter of each of a set of trees is plotted against age, the points for the individual trees will be scattered along a line (as seen in Figure i). Regression analysis is simply a method of calculat- ing the line which best fits the scatter. The line may be straight, as in this case, or curved. As it is straight the rate of increase in diameter is treated as constant. It is 0.263 cm (2.63 mm) each year. The radial increment is half this, that is 1.32 mm each year which is, of course, also the average width of the annual rings. </p><p>The trees planted in 1703-04 all show a high density of knots in the lower part of the radial longitudinal sections (Figures 2a and b) which extends to about 1.5 to 2.0 m from the ground. Trees planted later as replacements entirely lack this feature (Figure 2c). </p><p>DISCUSSION </p><p>The relation between diameter and age shows no evidence of a decline in radial growth-rate with age and is adequately described by the linear regression. This gives a mean annual radial increment of </p><p>250 </p><p>This content downloaded from 160.94.45.157 on Wed, 31 Jul 2013 07:31:50 AMAll use subject to JSTOR Terms and Conditions</p></li><li><p>NOTES </p><p>.. </p><p>3m i ' </p><p>2m | " ''t </p><p>1m -- ;i </p><p>_ </p><p>am </p><p>a b </p><p>I </p><p>3'1 ;, </p><p>0. 1 ..\ 11 </p><p>5 </p><p>j </p><p>I </p><p>Ir </p><p>c </p><p>Figure 2. The distribution of knots and buried branches in the radial longitudinal section of trunks of two of the yews from the Privy Garden at Hampton Court planted in 1703-04 (a and b) and one planted in </p><p>I8I5 (c). The broken lines are levels above the ground; the shaded area is decayed wood. </p><p>1.32 mm year- which is similar to the values established by Rose (1864) from Thiiringen in Germany but significantly less than the average rates of 2.0-2.5 mm year-1 given by Lowe (I897). The rates summarized by Lowe were usually based on measurements of circumference of trees in widely scattered localities, mainly in western Europe, for which the date of planting was known. The majority like those at Hampton Court were unshaded and in gardens or churchyards. </p><p>The oldest trees at Hampton Court were clipped when young. Those trees planted in 1703-04 have a high density of small knots in the central part of the trunk up to a height of 1.5-2.0 m from the ground. The pattern shows that they were clipped into narrow cones and this is confirmed by </p><p>ACKNOWLEDGEMENTS </p><p>I thank Mr Simon Thurley, Mr Terry Gough and Mr Graham Dillamore for their help in obtaining the sections and transporting them to Cambridge. </p><p>contemporary drawings. They were subsequently allowed to grow up, so that the original branching became incorporated into the trunk. This treatment might account for the slow rate of growth but this is not supported by the growth-rate of those trees which were planted after 800oo. The trunks of these trees lack the high density of knots and were apparently allowed to grow freely from the begin- ning. Their growth rate is not significantly different from the original trees. </p><p>The data provide a basis for est...</p></li></ul>

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