The secondary bracts in Aims and
Betula are small, and scale-like in comparison with those in the other four genera.
As part of the
Betula protocol, the following predetermined criteria, which were recorded at the health and cognitive examinations, were used as a guide for an extended evaluation as determined by the senior geropsychiatrist (R.A.): MMSE score [less than or equal to] 23, a decline in cognitive performance compared with a previous test occasion (from high to average/low or from average to low), a decline in daily functional activities or a subjective loss of memory function expressed by the participant in the semistructured interview, and any other behavioral or cognitive deviations, for example, confusion or disorientation noticed by the testing team.
Today, tree growth of
Betula reaches tree-line positions about 200 higher than that of Pinus in the study region.
Besides spruce, other boreal species also occur, including
Betula humilis Schrank or Vaccinium oxycoccos L.
In Pakistan, Himalayan musk deer inhabits sub- alpine scrub, usually found between 3000m and 4000m in association with
Betula utilis or in Gilgit area Juniperus polycarpus (Green, 1986).
For the Viru extracted peatland only Oxycoccus palustris and for the Visusti peatland
Betula pubescens and Eriophorum vaginatum were identified as indicator species.
Mazalape liepa (Tilia cordata Mill.) 32,7 [+ or -] 2,8 Paprastasis kastonas (Aesculus hippocastanum L.) 31,4 [+ or -] 2,4 Uosialapis klevas (Acer negundo L.) 30,9 [+ or -] 2,3 Paprastasis azuolas (Qercus robur L.) 27,8 [+ or -] 2,2 Paprastoji liepa (Tilia x vulgaris Hayne) 21,4 [+ or -] 2,1 Karpotasis berzas (
Betula pendula Roth.) 22,9 [+ or -] 1,8 Plaukuotasis berzas (
Betula pubescens Ehrh.) 18,2 [+ or -] 3,2 Paprastasis klevas (Acer platanoides L.) 25,6 [+ or -] 1,5 Paprastoji pusis (Pinus sylvestris L.) 30,6 [+ or -] 2,1 Grakscioji liepa (Tilia euchlora K.
Juglans regia, Quercus spp, Picea smithiana,
Betula utilis and Acer ceasium ranked second in the category of fuel wood.
Only 8 specimens from this list (Callitriche intermedia, Circaea alpina, Salsola kali, Swertia perennis, Lunaria rediviva, Cakile maritima, Dentaria bulbifera,
Betula nana) have survived in the herbarium.
2-4 m) grey birch,
Betula populifolia Marshall, on the edge of large block of deciduous forest.
TABLE 1.--Average number of trees per hectare and relative density values Number of trees per hectare Species 1981 1986 1991 1996 2001 2006 Tsuga canadensis 245.8 227.1 211.8 200.0 186.1 176.4 Acer rubrum 88.9 88.2 88.2 88.2 84.0 73.6
Betula alleghaniensis 47.9 45.8 41.7 36.1 32.6 27.8
Betula papyrifera 38.2 36.1 28.5 20.1 9.7 7.6 Acer saccharum 38.2 38.2 41.7 41.7 41.0 37.5 Pinus strobus 20.8 20.1 19.4 18.8 16.7 16.0 Quercus rubra 15.3 15.3 14.6 14.6 14.6 14.6 Fraxinus pennsylvanica 6.9 6.2 6.2 5.6 4.2 2.8 Fagus grandifolia 3.5 3.5 3.5 3.5 3.5 4.9 Tilia americana 2.8 2.8 3.5 3.5 3.5 2.8 Fraxinus nigra 1.4 0.7 0 0 0 0 Picea sp.
Key words: Alces alces,
Betula pendula,
Betula pubescens, birch, browsing, damage, decay, discoloration, moose, wood quality.