Two crofts in Saltsjöbaden: Skutudden and Igelboda

The croft cottage at Skutudden in Saltsjöbaden
In 1914 my mother lived here at Skutudden in a house which is now demolished. The crofter family was an old couple living here with their two cows and a pig. They grew what was needed for their animals and themselves and certainly, fishing was of great importance. At that time the landscape was open and light - nowadays it is quite dark because of all trees. Though still in 1948 when my mother used to take me here, this was still a beautiful and light farming landscape.
Dating two samples from the cottage
When the croft cottage at Skutudden in Saltsjöbaden was renovated almost all replaced old wood was thrown away and burnt. Only two pieces were left, which I later got for a dendrochronological investigation.

The result of this investigation shows that
the oldest sample - which looks as reused timber - was cut in the winter of 1732/1733,
the other sample was cut in the winter of 1796/1797.

It is puzzling that the sample from 1732 matches better towards a reference from the distant Dalarna than towards a reference from the nearby Nämdö (corrcoeff=0.45) or Tyresö (Sisshammar, corrcoeff=0.38 - not shown here). Accordingly we have reasons to guess that the house is partly built out of reused wood bought from elsewhere.
More samples from the cottage might reveal more of the story of this building.

SNSU02
The sample dated to 1732
SNSU02
The sample dated to 1732
This side of the timber (dated to 1732) was certainly cut long time ago - probably when the house was built. In the middle of the cut we can see half a hole for a dowel (a thick stick) used to keep two wood blocks in position. The diameter of the hole is 35 millimetres (1.4 inches). The length of the hole is 80 millimetres (3.2 inches). This is how it looks when old timber has been reused when a house was built. We find holes, grooves and notches which obviously were created when the block was first used for another building.
SNSU01
The piece from 1796 has red paint on what has been the outside.
The inner side has been tapped with small pins which certainly have been used to support clay plaster on the wall.
How was this dating done?
The sample from 1732 (SNSU02)
The wood was carefully ground.
The wood is infested by the common furniture beetle (Anobium punctatum).
Two radii were first measured with CooRecorder.
The data was then imported into CDendro and a mean value curve was created out of the two radii.
The mean value curve of the two radii was then compared to a mean value curve from the nearby island of Nämdö some 17 miles East of Saltsjöbaden.
(Our curve from Saltsjöbaden does not reach longer back than to the year 1765 with at least three trees behind each ring width value. So it is not very useful in this case.)
 
SNSU02_2.d12 Transformation: Proportion of last two years growth (2,0,T) 
compared to the reference Namdo_1.d12  Dated to 1995 
Minimum overlap used when finding best match: 35 
Table sorted by TTest 
--Rel Over   Corr TTest  BaPi   GLK  (year) 
-year  lap  coeff        corr 
   13   53   0.46   3.7  0.52  0.68  (1982) 
  263   53   0.45   3.6  0.37  0.55  (1732) 
  119   53   0.40   3.1  0.45  0.64  (1876) 
  134   53   0.34   2.6  0.30  0.58  (1861) 
   65   53   0.34   2.6  0.29  0.58  (1930) 
  346   53   0.32   2.4  0.34  0.66  (1649) 
    2   53   0.30   2.2  0.23  0.60  (1993) 
  214   53   0.26   1.9  0.30  0.62  (1781) 
The very big problem with this sample is that we have too few rings! At least we need some 60-80 rings to make a reliable dating, here we have only 53.
Also, the TTest-value (T-value) should be well above 5 to make a dating reliable. Here the highest is only 3.7!
Next step is to run the Test Towards Reference command from a collection of 37 members, each representing a mean value curve from an area in Sweden, Norway, Denmark, Estonia or Finland. With that command we will get a list with the best matching years - one from each of these 37 members.
 
                  T-    Over 
           Corr   Test   lap  Year 
all...     0.57   4.94    53  1732   based on 37 members 
Norw014B   0.55   4.71    53  1910 
SödraDal   0.55   4.67    53  1732   Södra Dalarna,  Axelson, Israels. PISY 
SWED305B   0.53   4.50    53  1732   Björbo, Dalarna 
DALARNA    0.53   4.45    53  1732   Dalarna, Lunds universitet (EXTRATERR) 
SE006-La   0.51   4.24    53   775   Lappland, Lund (EXTRATERR) 
9M45678    0.51   4.23    53   399   Denmark (WestDK) Old version 
EXFin002   0.50   4.16    53   923   Fin002 N.Finland (EXTRATERR) 
Gagnef-s   0.50   4.11    53  1732   Gagnef-Djura 
.... 
Year numbers occurring more than once: 
 1732    7 
 1906    4 
 1843    2 
 1887    2 
 1934    2 
The year 1732 is obviously some sort of favourite!
If we now provisionally date our sample to 1732, we can use the Test Towards Reference command to get a list showing how well all our 37 samples match at that year.
By then using only the nine best matching members, we get this result:
 
                    T-  Over 
           Corr   Test   lap 
all...     0.66   6.31    53   based on 9 members 
SödraDal   0.55   4.67    53  Södra Dalarna,  Axelson, Israels. PISY  1362-2005 
SWED305B   0.53   4.50    53  Björbo, Dalarna  1451-2002 
DALARNA    0.53   4.45    53  Dalarna, Lunds universitet (EXTRATERR)  932-1888 
Gagnef-s   0.50   4.11    53  Gagnef-Djura  1362-1831 
NMVKMEAS   0.47   3.80    53  Kaptensudden, unknown origin in Stockholm area  1672-1870 
BratPIr    0.47   3.78    53  Mälardalen (Bråthen), questionable segments removed  1153-1904 
FINL2_4_   0.46   3.71    53  SouthEast Finland  536-2002 
SWED302N   0.45   3.64    53  Nämdö, Stockholm archipelago  1583-1995 
3EP281AV   0.45   3.60    53  Estonia Est002 (EXTRATERR)  1516-1998 
I.e. a mean value curve (see all... above) created out of these nine members gives us a correlation coefficient of 0.66 and a TTest-value of 6.3 for the match at the year 1732.
Such high values indicate a reliable dating!
The sample from 1796 (SNSU01)
SNSU01
SNSU01
Running the other sample from the cottage towards the Nämdö curve shows:
 
--Rel Over   Corr TTest  BaPi   GLK  (year) 
-year  lap  coeff        corr 
  199   63   0.48   4.2  0.49  0.71  (1796) 
  181   63   0.38   3.3  0.41  0.63  (1814) 
  124   63   0.35   3.0  0.32  0.70  (1871) 
   74   63   0.34   2.8  0.36  0.70  (1921) 
   36   63   0.32   2.7  0.39  0.57  (1959) 
The crossdating above towards the Nämdö mean value curve is not very convincing as the highest T-value is well below 5!
Doing an analysis (as for the other sample) with a collection of 37 mean value curves from the surrounding areas, we get the following best matches:
 
                           T-    Over 
                    Corr   Test   lap  Year 
all...              0.49   4.38    63  1796   based on 37 members 
swed304S            0.59   5.67    63  1796   Tyresö, Sisshammar (SE Stockholm 5913 1821) Andreason PISY 1661-1910 
East SvealandNOSU   0.58   5.59    63  1796   East Svealand (Aneby+Bettna+Sisshammar+Askersudn+SBaden exkl Skutudden 
swed328T            0.53   4.80    62  1796   Tyresta (SE Stockholm 5911 01816)  Linderholm PISY 1734-2000 (cropped) 
ANEBYALL            0.55   4.69    52  1796   Aneby in Småland 
3EP281AV            0.50   4.45    63  1796   Estonia Est002 (EXTRATERR) 
DALARNA             0.49   4.41    63  1796   Dalarna, Lunds universitet (EXTRATERR) 
Karesuan            0.50   4.26    56  1828   Karesuando, Sweden 
SWED302N            0.48   4.24    63  1796   Nämdö, Stockholm archipelago 
se_005Go            0.47   4.19    63  1796   Gotland, Lunds univ. (EXTRATERR) 
As seen above, the year 1796  is a strong contender!

With the sample dated to 1796 and with only the nine best matching mean value curves selected:

 
                             T-  Over 
                    Corr   Test   lap 
all...              0.66   6.91    63   based on 9 members 
swed304S            0.59   5.67    63   Tyresö, Sisshammar (SE Stockholm 5913 1821) Andreason PISY 1661-1910 
East SvealandNOSU   0.58   5.59    63   East Svealand (Aneby+Bettna+Sisshammar+Askersudn+SBaden exkl Skutudden 
ANEBYALL            0.55   4.69    52   Aneby in Småland 
swed328T            0.53   4.80    62   Tyresta (SE Stockholm 5911 01816)  Linderholm PISY 1734-2000 (cropped) 
BratPIr             0.51   3.89    45   Mälardalen (Bråthen), questionable segments removed 
3EP281AV            0.50   4.45    63   Estonia Est002 (EXTRATERR) 
DALARNA             0.49   4.41    63   Dalarna, Lunds universitet (EXTRATERR) 
SWED302N            0.48   4.24    63   Nämdö, Stockholm archipelago 
se_005Go            0.47   4.19    63   Gotland, Lunds univ. (EXTRATERR) 
With a TTest value near 7, this means that the dating to 1796 is reliable!
The measurement series are available within this .rwl file: SNSU.rwl

The croft cottage at Igelboda, Saltsjöbaden

Bild hämtad ur G. Lindberg: Saltsjöbadens historia, 1959. Fotograf okänd.
When the old croft cottage was demolished in 2006, I got two samples, one from a wall near the entrance and the other from a stock laying on the ground partly in the clay under the chimney shaft.
SNIT01
This one comes from the external wall as seen by the red paint.
It has been infested by small and big woodworms -
the common furniture beetle (Anobium punctatum) and the house longhorn beetle (old-house borer, Hylotrupes bajulus).
This tree was cut in the winter of 1849/1850.
SNIT02
This tree was cut in 1787 or possibly a few years later.
SNIT02
The sample from 1849 (SNIT01)
 
2009-01-26  21:51:48 Cybis CDendro, Algorithm: Proportion of last two years growth (2,0,T) 
Correlations between available references in D:\ake\tree\All\all.fil and 
D:\ake\tree\sn\Igelboda\SNIT01.d12 
based on best matches giving dating to years according to the year-column below and with overlap >= 47 
Results sorted according to decreasing T-Test values. 
                           T-    Over 
                    Corr   Test   lap  Year 
all...              0.44   4.41    81  1107   based on 37 members 
swed304S            0.61   6.86    81  1849   Tyresö, Sisshammar (SE Stockholm 5913 1821) Andreason PISY 1661-1910 
swed328T            0.56   6.09    81  1849   Tyresta (SE Stockholm 5911 01816)  Linderholm PISY 1734-2000 (cropped) 
se_005Go            0.56   6.02    81  1849   Gotland, Lunds univ. (EXTRATERR) 
BratPIr             0.56   5.16    60  1849   Mälardalen (Bråthen), questionable segments removed 
SWED302N            0.49   5.06    81  1849   Nämdö, Stockholm archipelago 
FINL2_4_            0.48   4.82    81   648   SouthEast Finland 
swed016_            0.48   4.66    74  1849   Glaskogen, swed016 
.... 
Year numbers occurring more than once: 
 1849   11 
 1770    2 
 1792    2 
With only the best 5 matching curves and the sample provisionally dated to 1849: 
_ 
2009-01-26  21:58:35 Cybis CDendro, Algorithm: Proportion of last two years growth (2,0,T) 
Correlations between available references in D:\ake\tree\All\all.fil and 
D:\ake\tree\sn\Igelboda\SNIT01.d12 
dated to 1849 with corr >= 0.49 and with overlap >= 60 
Results sorted according to decreasing correlation coefficient values. 
                    T-  Over 
           Corr   Test   lap 
all...     0.64   7.45    81   based on 5 members 
swed304S   0.61   6.86    81  Tyresö, Sisshammar (SE Stockholm 5913 1821) Andreason PISY 1661-1910  1661-1910 
swed328T   0.56   6.09    81  Tyresta (SE Stockholm 5911 01816)  Linderholm PISY 1734-2000 (cropped)  1734-2000 
se_005Go   0.56   6.02    81  Gotland, Lunds univ. (EXTRATERR)  1125-1987 
BratPIr    0.56   5.16    60  Mälardalen (Bråthen), questionable segments removed  1153-1904 
SWED302N   0.49   5.06    81  Nämdö, Stockholm archipelago  1583-1995 
The tables above clearly show that 1849 is a correct dating of the sample taken from the wall.
The sample from 1787
 
2009-01-26  22:04:28 Cybis CDendro, Algorithm: Proportion of last two years growth (2,0,T) 
Correlations between available references in D:\ake\tree\All\all.fil and 
D:\ake\tree\sn\Igelboda\SNIT02.d12 
based on best matches giving dating to years according to the year-column below and with overlap >= 53 
Results sorted according to decreasing T-Test values. 
                           T-    Over 
                    Corr   Test   lap  Year 
all...              0.53   5.87    91  1787   based on 37 members 
swed304S            0.65   8.06    91  1787   Tyresö, Sisshammar (SE Stockholm 5913 1821) Andreason PISY 1661-1910 
East SvealandNOSU   0.60   7.15    91  1787   East Svealand (Aneby+Bettna+Sisshammar+Askersudn+SBaden exkl Skutudden 
SWED302N            0.53   5.90    91  1787   Nämdö, Stockholm archipelago 
swed328T            0.59   5.22    53  1787   Tyresta (SE Stockholm 5911 01816)  Linderholm PISY 1734-2000 (cropped) 
BratPIr             0.49   5.02    82  1787   Mälardalen (Bråthen), questionable segments removed 
..... 
The table above clearly shows that 1787 is a correct dating of the sample that was picked up from the ground in the clay under the chimney shaft.
A few rings may be missing in the outermost part of the stock - meaning that the tree was cut some years after 1787 - though I do not think so!
The measurement series are available within this .rwl file: SNIT.rwl
This is the new house which replaced the old one (which was in very bad condition).


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