Forest Condition in Europe - ICP Forests

82 Forest Condition in Europe 2013
6.2. Ireland
Ireland completed a Level I forest condition survey in 2012. Twenty plots were surveyed in
2012 for crown damage in the form of crown defoliation and where recorded the damaging
agents were reported where possible as was the extent of the damage through the affected tree
crown. Surveys were conducted by a trained assessor and both training days and data quality
assurance and data quality control measures were employed. All of the twenty surveyed plots
coincide with areas surveyed through Ireland’s National Forest Inventory. Four tree species
are included in the survey, Sitka spruce (Picea sitchensis), lodgepole pine (Pinus contorta),
Norway spruce (Picea abies) and Japanese larch (Larix kaempferi).
The annual assessment of crown condition was conducted on the Level I plots in Ireland between
July 25 th and October 25 th 2012. Overall mean percent defoliation was low in 2012 at
4.3% and represents an improvement in crown condition from recent year’s survey. In terms
of species, defoliation decreased in the order of Japanese larch (13.75% * ), lodgepole pine
(7.0%) > Sitka spruce (3.4%) and Norway spruce (1%). (*Tree sample numbers were low for
Japanese larch; just four samples).
The number of Level I plots has been rationalised in Ireland in recent years with all of the
sample plots migrating on a phased basis to coincide with locations of National Forest Inventory
plots in Ireland. The location of the new Level I plots has been selected objectively according
to the methods outlined in the manual of ICP Forests. This has been carried out due
to increases in forest cover in Ireland since the Level I crown condition survey commenced in
1987. Acknowledgement is made to the Forest Service, Department of Agriculture, Food and
the Marine.
6.3. Italy
The survey of level I in 2012 took into consideration the condition of the crown by 5081 selected
trees in 245 plots belonging to the EU network 16x16 km. The number of plants is reduced
compared to the survey of 2011, following the merger according to the methods of the
Inventory National Forest. The results given below relate to the distribution of frequencies of
the indicators used, especially transparency - which in our case we use for the indirect assessment
of defoliation and the presence of agents known causes attributable to both biotic
and abiotic. For the latter, not so much the indicators we analyzed the frequencies of affected
plants, but the comments made as to each plant may have multiple symptoms and more
agents.
Defoliation data are reported according to the usual categorical system (class 0:0-10%; class
1: >10-25%; class 2: >25-60%; class 3: >60%; class 4: tree dead): most (77.3%) is included in
the classes 1 to 4; the 35.7 % is included in the classes 2 to 4.
By analysing the sample for groups of species, conifers and broadleaves, it appears that conifers
have a transparency of less than deciduous foliage: 32.7% of conifers and 19.2% of
broadleaves are without any defoliation (Class 0).
The conifers falling in the defoliation classes 2 to 4 are 31.0% respect to the 37.5% of broadleaves.
From a survey of the frequency distribution of the parameter for transparency species divided
into two age categories (