5. FOREST HISTORY
The analysis of the charred wood from the local stratigraphy allows the reconstruction The analysis of the charred wood from the local stratigraphy allows the reconstruction of the use of the forest by
of the use of the forest by the settlers over a time span of more than six the settlers over a time span of more than six millennia.millennia.
The identified taxa show the presence and use of few main woodland associations.
The identified taxa show the presence and use of few main woodland associations.
Fig. 13 - Clay floor fragments from US 59, Early Medieval house, filled with bark and conifer needles.
Fig. 13 - Clay floor fragments from US 59, Early Medieval house, filled with bark and conifer needles.
Fig. 14 - Fragments of spruce wood boards with pre-combustion decay, from US 189, House A.
Fig. 14 - Fragments of spruce wood boards with pre-combustion decay, from US 189, House A.
1.
1. The coniferoThe coniferous forest, us forest, as shoas shown by wn by Pines aPines and Spruce/Land Spruce/Larch, whicrch, which was h was presentpresent since the Mesolithic occupation when, certainly due to the small size of the since the Mesolithic occupation when, certainly due to the small size of the sam- ple,
ple, onlonly Piy Pine wne wood ood seemseems to s to have have been been usedused. Ho. Howevewever, itr, its exs existeistence nce is cis contontinuoinuousus through the millennia up
through the millennia up to the Middle Ages (and to the to the Middle Ages (and to the present time), and seems topresent time), and seems to be t
be the mhe most ost impoimportanrtant ent envirovironmennment wht where ere both both firfirewood ewood and and timtimber ber wood wood was was col- col-lected. Spruce is probably the most
lected. Spruce is probably the most common conifer in the charcoal samples, with acommon conifer in the charcoal samples, with a lesser occurrence of larch. The
lesser occurrence of larch. The phyto-climatic association with Scots pine, Spruce,phyto-climatic association with Scots pine, Spruce, Larch, Arolla pine, Mountain pine with underwood with rhododendron and dwarf Larch, Arolla pine, Mountain pine with underwood with rhododendron and dwarf juni
juniper per is is charcharacteacterisristic tic of of thethe Vaccinion-PiceenionVaccinion-Piceenion, today well documented in the, today well documented in the Alto Adige/Sou
Alto Adige/South Tyroth Tyrol mountains, and therefore l mountains, and therefore on the slopes of on the slopes of the middle Isarcothe middle Isarco Valley (G
Valley (GAFTAAFTA and P and PEDROTTIEDROTTI, 1998). The absence of Fir (, 1998). The absence of Fir ( Abi Abies aes albalba) in the ) in the charcoalcharcoal samples is noteworthy.
samples is noteworthy.
2.
2. The oaThe oak-wood k-wood is the is the other other main foremain forest, st, largely largely used used all all over the over the archaeological archaeological periods.periods.
According to the charcoal spectrum this was formed, apart from a deciduous oak According to the charcoal spectrum this was formed, apart from a deciduous oak spe-cies, by broad-leaved species common at lower altitude, such as
cies, by broad-leaved species common at lower altitude, such as Carpinus/OstryaCarpinus/Ostrya (only (only in Neolithic layers), a species of
in Neolithic layers), a species of UlmusUlmus (only in (only in Neolithic and Iron Age layers) and, withNeolithic and Iron Age layers) and, with a greater
a greater continuitycontinuity,, Fraxinus Fraxinus andand Acer Acer . This association could be part of the phyto-cli-. This association could be part of the phyto-cli-matic unit
matic unit Fraxino Fraxino orni-Ostryon carpinifoliaeorni-Ostryon carpinifoliae, in which can usually be found various, in which can usually be found various oak species and, occasionally, Scots pine.
oak species and, occasionally, Scots pine.
3.
3. During sDuring several peeveral periods, ariods, at the t the edges edges of the of the oak woak wood, larood, large clege clearances arances allowed allowed the ex-the ex- pansion
pansion of Hof Hazel azel thickets. thickets. At hAt higher aigher altitude, ltitude, in in the the transitional transitional belt bbelt between etween the the Oak Oak andand coniferous wood, a heliophilous forest environment
coniferous wood, a heliophilous forest environment withwith Betula Betula could develop. could develop.
4.
4. At At the the upper upper limit limit of of the the oak oak wood wood the the presence presence ofof Fagus Fagus is attested only sporadically is attested only sporadically during the historical periods.
during the historical periods.
On the ground of
On the ground of charcoal analysis, we can observe a dramatic change in charcoal analysis, we can observe a dramatic change in the forestthe forest environment used for wood supply. Only two main ecosystems were systematically used, environment used for wood supply. Only two main ecosystems were systematically used, the meso-thermophilous broad-leaved forest, dominated by Oak, along the valley floor the meso-thermophilous broad-leaved forest, dominated by Oak, along the valley floor and the lower slopes, and the coniferous forest, covering the upper slopes. In the and the lower slopes, and the coniferous forest, covering the upper slopes. In the anthra-cology of the site,
cology of the site, it appears that the it appears that the relationship between these two main environmentsrelationship between these two main environments has deeply modified over the centuries, the main change occurring at the beginning of has deeply modified over the centuries, the main change occurring at the beginning of the historical period, when the coniferous forest becomes more and more important in the historical period, when the coniferous forest becomes more and more important in the wood supply.
the wood supply.
The data from the Mesolithic, though scarce, clearly show however that these two The data from the Mesolithic, though scarce, clearly show however that these two as-sociations were already settled on the slope, and both were close to the
sociations were already settled on the slope, and both were close to the site. During the Neo-site. During the Neo-lithic, probably due to an increased spread uphill of the Oak wood, almost 90% of the wood lithic, probably due to an increased spread uphill of the Oak wood, almost 90% of the wood used on the site comes from this association and from its openings (fig. 16). Four or five used on the site comes from this association and from its openings (fig. 16). Four or five millennia later, the situation has completely changed (fig. 17) and the thermophilous forest is millennia later, the situation has completely changed (fig. 17) and the thermophilous forest is present in the sample
present in the sample composition with less composition with less than 5%.than 5%.
A more detailed study of the nine Neolithic layers (US 30) does not show important A more detailed study of the nine Neolithic layers (US 30) does not show important changes in the forest composition, where the wood of
changes in the forest composition, where the wood of Oak and AlderOak and Alder, which are present in all, which are present in all samples, has constantly been collected. Conifer wood is present in six layer of nine, perhaps samples, has constantly been collected. Conifer wood is present in six layer of nine, perhaps suggesting a lesser availability of that environment as, for instance, because of increased suggesting a lesser availability of that environment as, for instance, because of increased distance from the site. On
distance from the site. On the basis of frequency analysis for the basis of frequency analysis for layer, it appears that only in thelayer, it appears that only in the layer 6 and 7 wood collection interested a larger number of plants (fig.
layer 6 and 7 wood collection interested a larger number of plants (fig. 18).18).
Subsequently the number of species decreases, with a minimum (two taxa only) in the Subsequently the number of species decreases, with a minimum (two taxa only) in the layer 4. Whether this might be due to human choice, or to
layer 4. Whether this might be due to human choice, or to a casual selection of sample, or toa casual selection of sample, or to a short period of settling, or to other
a short period of settling, or to other reasons, is an open question.reasons, is an open question.
Fig. 15 - Elm branch with evidence of pruning at an edge.
Fig. 15 - Elm branch with evidence of pruning at an edge.
Neolithic Neolithic n = 424 n = 424
Quercus Quercus
Corylus Corylus
Carpinus/Ostrya Carpinus/Ostrya
Alnus sp Alnus sp Picea excelsa
Picea excelsa Picea/Larix Picea/Larix Populus
Populus Prunus cf avium Prunus cf avium
Acer Acer Ulmus Ulmus Fraxinus Fraxinus
Prunus Prunus
Fig. 16 - Charcoal spectrum from the Neolithic layers, Trench C.
Fig. 16 - Charcoal spectrum from the Neolithic layers, Trench C.
Fig. 17 - Charcoal spectrum from the Late Roman layers (4
Fig. 17 - Charcoal spectrum from the Late Roman layers (4thth-5-5thth centuries AD). centuries AD).
Late Roman Late Roman
n = 728 n = 728
Picea/Larix Picea/Larix Picea excelsa
Picea excelsa
Pinus Pinus sylvestris/mugo sylvestris/mugo Juglans
Juglans Fraxinus
Fraxinus
Alnus Alnus
Corylus Corylus Quercus
Quercus Acer Acer
Betula Betula
Fig. 18 - Tree taxa frequency variation in the Neolithic layers.
Fig. 18 - Tree taxa frequency variation in the Neolithic layers.
0 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7
ttgg11 ttgg22 ttgg33 ttgg44 ttgg55 ttgg66 ttgg77 ttgg88 ttgg99
t t a a x x a a
n n . .
Fig. 19 - Barley (
Fig. 19 - Barley ( Hordeum vulgar Hordeum vulgaree), US 216, oven M1, Early Roman Empire.), US 216, oven M1, Early Roman Empire.