EON TREE REPORT
Christopher J. Earle, 16-Jun-1999

SAMPLING:

Tree was sampled by Michael Taylor, Bob Van Pelt and Christopher J.
Earle on 11-May-1999 at Humboldt Redwoods State Park, under permit
from Parks Dept. Tree had fallen at least 5 years earlier across a trail
and had previously been sectioned. The sectioned area was approximately
20 m above tree base and had a trunk diameter of approximately 140 cm.
Original cause of tree death unknown. Stand is currently late
successional redwood with most stand dominants having dbh over 2 m. Dead
tree appeared to have been codominant, perhaps suppressed and with a
reduced crown depth relative to its neighbors. Sampling was performed
with a chainsaw. Sampled piece is 20-23 cm wide and 70 cm long, including
pith and 20 mm of sapwood. Bark was much degraded and several
millimeters of sapwood may be missing. 

PREPARATION:

At sampling, sample broke into two pieces along a ring boundary. Break
may have coincided with fire scar; it is likely that several years of
record were lost in the break. Pieces were glued and sample was cut into
two matching slabs on a bandsaw. At the time, sample was very wet.
Subsequently one piece was air dried and the other was preserved with
PEG-1000. The PEG sample is still soaking at this time (16 June 1999)
and will be processed in 2-4 weeks. The dried sample developed many
small checks upon drying. It was subsequently sanded with sanpapers to
600 grit, prodiucing a finish sufficiently fine to resolve cell walls.

COUNTING:

Beyond the initial decade, the sample proved to have extremely fine
rings. Many rings were discontinuous, displayed for only a few cm of the
sample width. Many rings are less than 5 cells wide and in a few cases
rings could be discerned with a little as 3 cells. These circumstances
suggest that the small size of the sample, representing ca. 8.8% of the
cross-sectional area of the stem, has resulted in non-representation of
many rings. Counting proceeded along an irregular radius selected to
follow the areas of locally wide rings. Counting along this initial
radius revealed a total of 2014 rings. On a portion of the sample it was
possible to count a second radius, which added 12 rings to this count
for a total of 2026 sequential rings counted in the sample. This total
is an underestimate of sample age for these reasons:

1. Missing rings in the sample break (perhaps a fire scar) and outermost
sapwood.

2. A small portion of the stem circumference is represented; some rings
may only have been formed on a different side of the tree.

3. Many rings are very small, at the lower theoretical limit of
resolution (i.e., 2-3 cells). This suggests that there may be many years
in which no ring was formed.

4. The sample has already begun to experience significant decay. In
portions of the sample, cell boundaries cannot be discerned and the wood
is distinctly 'punky'. It is hoped that better ring definition will be
found in these areas when the sample treated with PEG is analysed.

5. However, there is also a possibility that redwoods can produce 'false
rings', i.e., produce more than one ring in a growth season. I am making
enquiries in this connection. If this proves to be true, then the ring
count of this tree will bear no discernable relationship to its
chronological age; the rings on the sample are for the most part too
narrow to determine if they are 'false' or 'true.'

TREE AGE

Assuming that there are no false rings, the sample is at least 2026
years old. Based on observed problems with circuit uniformity and
variable ring width, it is plausible that as many as 10 percent of the
rings that might have been formed, are not present in the sample. Thus
(again, assuming no false rings) I have high confidence that the true
age of the sample's pith is 2026 to 2228 years, while there is a lesser
possibility that it is older. To this must be added the time it took for
the tree to grow to the height of the sample, which was probably 30-60
years, suggesting a total tree age of 2056 to 2288 years. This compares
with a maximum reported age for redwood of 2200 years.

CONCLUSION

A full sample might show this to be the oldest known redwood (apart from
the fact that it is dead), but based on the available data the minimum
limiting age for the sample is 2026 years. I would assign a best-guess
sample age of 2100 years from pith to tree death based on current data.