Experiments with beech seedlings, Fagus syl
vatica L . , were conducted to investigate from the roots, decreased buffering capacity of the leaf ' s apoplast and increased transpi exchange reactions between the infiltrating mist an� the symplast must take �lace to leach K in great�r amounts; NH4 could match this need while H would exchange mainly with cell walls .
Generally, the leachability of cations from field-grown plants is greater than that from laboratory experiments. This increased leachability is probably due to several en
vironmental ;i,mpacts on the plant, such as lesions on the leaf surface or higher per
meabilities of the membranes .
Increased transpiration of the seedlings in hydroponic solution could be induced by the acid mist treatment, too . However, the decreased diffusive resistance of the stomatas of potted plants was detected only at night . Consequently, the greatly increased trans
piration of the seedlings in water culture
Air Pollution and Forest Decline ( J . B . Bucher and I . Bucher-Wallin, eds . ) .
Proc . 1 4th Int . Meeting for Specialists in Air Pollution Effects on Forest Ecosystems , IUFRO P2 . 0S , Interlaken , Switzerland , Oct . 2-8 , 1 98 8 . Birmensdorf , 1 98 9 , p. 47 4-476 .
VISIBLE SYMPl'CM, OF N?� SPRUCE DE.CLINE Jerzy A.I.esifiski and Lars Westman
·Swedish University of Agricultural Sciences , Depart:Jrent of Silviculture 901 83 Urrea, Sweden
University Ulea, Departrrent of F.cological Botany and 901 87 Urrea, Sweden
AB.5TRACT
Within the crown of Norway spruce the natural p:rocesses of bianass production, destruction and re
generation proceed dependent on tree age. The intensity of these processes during a tree�s lifetime vary, which gives rise to a gradual µansition of patterns in branch rrorph:>logy within particular parts of the crown.
The various factors causing forest decline interact with the processes brought about by senescence and together prcduce visible syrrptans of crown injury in Norway spruce. Distinguishing between symptans
attributed to the natural alterations in crnwn structure and those caused by different injurious factors is possible, although not easy. In Norway spruce which is, in teDTIS of crown rrorph:)logy, rrore differentiated than any other European tree species , the proper diagnosis is especially difficult.
In this paper different patterns of branch mal
fo:anation occurring in various branching habits in Norway spruce are presented. These patterns seem to be very useful for the invento:ry and diagnosis of factors causing different types of decline in Norway spruce.
INTIDDOCTICN
Norway spruce is one of the rrost serious! y en
dangered tree species in Europe. Spectacular symptans of it�s decline are the crown transparency and malfonn
ation of the crown structure. These syn;itans are express ed due to various factors caused alteration of the processes of bianass production, destruction and re
generation proceeding simultaneously within the crown.
The intensity of each process depends on the age of a spruce tree and on the factor oonplexes contributing in a given type of decline (I.esili.ski and Lan:'lmann 1 988) . Therefore, many different patterns of branch malfo:an
ation may occur in the spruce crown when the tree is affected by haJ:mful agents (I.esili.ski and Landmann 1 988) •
The aim of this paper is to present some examples of the rrost cx:moon patterns of branch malformation occurring in various types of crown injury in spruce
(Westman and I.esili.ski 1 986 , I.esili.ski and Westman 1 987 , I.esili.ski and Landmann 1 988) . These patterns are srown for each branching habit separately.
MATERIAL AND METHODS
About 800 spruce trees, situated in rrore than 40 Scandinavian localities, have been examined. M::>st of them were situated in southern Sweden. No less than one fourth of the total mnnber of trees examined have been cut down in order to gather sare details concerning branch rrorph:>logy, which could not be seen on the stand
ing tree. The results of those investigations have been
474
published previous! y (Westman and I.esili.ski 1 985 , 1 986) . All spruce crowns were scanned through binoculars , as oarmonly practised in forest inventory. M::>re than 70 detailed variables were recorded for each tree crown
(Westman and I.esifiski 1 986 , I.esili.ski 1 988) • After elaboration of the gathered data, b.o integrative measures of injury in Norway spruce , which can be used in an inventory practice , have been found (Westman and I.esili.ski 1 986, I.esili.ski and Westman 1 987 , I.eSili.ski and Landmann 1 988) •
RESULTS
Examined trees represented seven branching habits in spruce, however, only five of them were represented in quantities satisfactory with respect to the aim of this paper. They are as follows : cx::mb--, hanging brush-, cx:moon brush-, thin brush-, and cx:nm:m flat branching habits (Westman and I.esili.ski 1 986) •
Each spruce tree belonged to one of four categories of crown injury or was classified as l]ealthy, i.e. with
out any visible syn;itans of injury within the crown (Fig. 1 ) • When a developnent stage or character of injury was also considered the trees were classified as
representing one of twelve crown injury types , which belong to above mentioned categories. The developnent
stages of injury (initial, transitional or terminal) are considered when the injury seems to progress continuously, otherways they are called incidental or permanent (I.esili.ski and Landmann 1 988) •
Malfonnations of branch structure appear due to various causal agents , which hasten or retard the physiological processes occurring within the crown, viz . - continuous yearly production of primary shoot bianass , - continuous destruction of the oldest living bianass , - continoous replacerrent of the lost bianass with and
secondary shoots .
In the fonnation of branch malfo:anation patterns in Norway spruce, bianass destruction beginning fran the
shoot tips is also of :inportance.
I.esili.ski and I.andmann (1 988) distinguished three groups of branch malfo:anation (injury) patterns , which may occur within spruce crowns when the trees becane old or when they are affected by haJ:mful agents . During field studies carried out this year it became obvious , that one rrore group should be included. l\ccordingly, these groups are as follows :
- group D, in which bianass DESTROCTION is rrost evident, - group DR, in which the DESTRUCl'ICN of biomass is still
evident, but bicimass REGENERATION has 1mdoubtedly begun,
- group ID, in which the bianass DESTRUCTICN is rrore or less balanced by it�s REGENERATION, and
- group R, in which the REGENERATION of bianass is
daninant.
window type
unifonn t
healthy tree
type top
peripheral t
Fig. 1 • categories of crown injw:y in No:i:way spruce In each group the particular series of branch mal
fonnation patterns may ==. They differ from each other dependent mainly on the prevailing manner of bianass de
struction (only outwards or simultaneously outwards arrl inwards along the branch) arrl on the intensity of the lateral-shoot drop (Lesinski arrl Landmann 1988).
Fonnation arrl appearance of the particular branch malfonnation patterns depends strongly on branching habits in No:rway spruce. In sorre branching habits sane pattern series do not oc= or are represented very seldan. In Figures 2 - 6 are slu..m selected examples of the m::>st cx:mron branch malfoIJt1ation patterns, which may be exhibited in crowns of spruce trees representing particular branching habits. lt>re examples of these patterns will be presented in the near future (Lesinski
1 988).
" ''�T,4"
Mff P'Wf$Pr �
• G r o u p "D"
G r o u p "DR"
G r o u p "RD"
Fig. 2. Exarrples of the branch malfonnation patterns occi=ing in spruce crowns representing the comb branching habit
G r o u p "D"
G r o u p "RD"
-
--�-�¾ --,,__,j(��" Ii � _,_, -,r
G r o u p "R"
Fig.3. Exanples of the branch malfonnation patterns occurring in spruce crowns representing the hanging brush branching habit
G r o u p "D"
G r o u p "DR"
G r o u p "RD"
G r o u p "R"
Fig. 4. Examples of the branch rnalfonnation patterns occurring in spruce crowns representing the COill!On brush branching habit
G r o u p "D"
- ,. /17'��
G r o u p "RD"G r o u p "R"
Fig. 5. Examples of the branch rnalfonnation patterns occurring in spruce crowns representing the thin brush branching habit
476
G r o u p "D"
G r o u p "RD"
Fig. 6. Exanples of the branch rnalfonnation patterns occw:ring in spruce crowns representing the o.:mnon flat branching habit