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In this paper, the problem of flower bud formation influence by shading, and day length for three years Sugi seedlings (Cryptomeria japonica D. DON) is discussed.
(1) Experimental plots contained the seedlings grown at 100%0, 50%, 25%, and 15% of full sunlight were set in running water bed, and 12 pots planted with one seedling for lach were laid in the spring, 1957.
And then the flower bud formation was observed during the next growing season, and the following results obtained.
The seedlings grown at 1590 of full sunlight formed no flower buds, the 50% ones formed more than the 25% of full sunlight seedlings.
The seedlings grown in full sunlight showed the best flower bud formation.
(2) Concerning day length the three kinds of experiments were carried out, and the following results were obtained.
The 8 hours lighted seedlings formed no flower bud. The 16 hours lighted (12 hours sunlight and 4 hours electric light) two seedlings formed flower buds out of 20.
In the last case, 16 seedlings grown in full sunlight formed flower buds out of 20.

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Pyroligneous acid (wood vinegar) can be collected easily as a by-product of charcoal making which is one of common manufacturings in Japanese forestry villages and is effective as a soil disinfectant in forestry nurseries according to NORARA'S investigations.
The author previously reported that the acid was toxic upon spore germination and mycelial growth of some plant pathogens not only as a drench but also as a fumigant and penetrated into the soil considerably and these characters might be associated with the disinfectant effect of the acid in the soil. The present paper dealt with some researches of microbial succession on the upper layer (0_??_5cm. depth) of the treated soils for about 1 year after the drenching with the acid by aid of the dilution plate method.
The main results observed on the treated soils comparing to the untreated were as follows:
1. Numbers of fungi decreased considerably at immediate several days after the drenching. Following this temporary depression there was a pronounced increase in the total numbers within 2 weeks and the high population was kept even at 1 year later.
2. Numbers of bacteria decreased at first, then increased conspicuously by 2 weeks after the drenching like that of the fungi, but by 3 months, they droped to the normal level.
3. Actinomycetes also reduced in numbers by the drenching and were thought to be not active in the soil again even at 1 year later. 4. Dominant fungi on the treated soils were Penicillium janthinellum series, P. citrinum series, P. oxalicum series and Trichoderma viride though these species were also detected considerably in the untreated soils.
5. Penicillium javanicum series were detected considerably from the treated soils in the following periods, elapsed about 3 months after the drenching.

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In 1958, a needle rust occurred on Pinus strobus L. (eastern white pine) planted in 1955, at the Tokyo University Forest, Hokkaido. An infected pine, which bore spermogonia on the needle, was digged out and brought into the green house. Peridermia were formed on these needles after 21 days replacement. The aecidiospores formed on these peridermia were used for inoculation. On the other hand, seeds of Eupatorium sachalinense MAKINO (Yotsuba Hiyodoribana) were collected from the field, and sown in pots in green house. These young Eupatorium were inoculated with aecidiospores. After 11-13 days inoculation, urediosori were formed on the undersurface of the leaves of these plants. Thus, the alternate host of the needle rust of P. strobus was E. sachalinense and the causal organism was Coleosporium Eupatorii ARTHUR, which also causes a needle rust of Pinus koraiensis SIEB. et Zucc.

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Vorliegender Berichte handelt über Verteilungen der als Dominant vorkommenden Borkenkäfer an den Stämme der Fichten, Befalltypen, Reihenfolge der Angriffe und Verfärbungs-oder Abfallformen der Nadeln von befallenen Bäume. Die Beobachtungen wurden während der Jahre 1956_??_1958 in des Fichtenbestand (ca. 50 jährig) in Hokkaido Forst der Universität Tokyo ausgeführt.
1) Synokölogisehe Analysen an den befallenen stehenden Fichten sind ii dem Tab. 3 dargestellt.
Me Arten der Borken-, Bock- und Rüssei-Käfe-r, die an den befallenen stehenden stämme gefunden wurden, sind auf den Seiten Hylurgops inouyei genannt. Von ihnen trat folgende vier Arten als Dominant auf: Ips typographus f. japonicus, Cryphalus piceus, Pityogenes seirindensis und Polygraphus jezoensis. Als Dominant soil die Borkenkafer, deren Frassbilder. über 2/3 einer Probenfläche am stamm decken, kennzeichnet werden (Tab. 1).
3) Vertikale Verteilung der Dominierungsprozente von drei wichtigen Borkenkäfern an den stämme ist in der Abb. 1 dargestellt. In 1956 war die Dominierungsprozent der Ips typographus an allem Abschnitt der stämme sehr hock. Aber in 1956 verminderte sie sich ziemlich an den mittleren und oberen stämme, dagegen Verstärkte die der Cryphalus piceus sich. Pityogenes seirindensis dominierte bevorzugt an den obersten stamme.
4) Wenn einer Befalltypus der stehenden Fichte durch Borkenkäfer mit als Dominant auftretenden Arten kennzeichnet werden, wurden in unserem Bestand folgende Typen beobachtet:
Nr. 1 typographus-typus
Nr. 2 piceus-typus
Nr. 3 seirindensis-typus
Nr. 4 Komplex-typus, der (a) typographus-piceus-typus, (b) typographus-seirindensis-typus, (c) typographus-jezoensis-typus, (d) typ.-pic.-seirin.-typus einschliesst. Jahriges Entstehen der oben genannten Befalltypen ist in dem Tab. 3 dargestellt.
5) Reihenfolge der Angriffe: (1) Angriff wurde gewöhnlich mit Ips typographus begonnen. (2) Cryphalus piceus-und Pityogenes-Angriffe greichzeitig mit oder sofort nach typographus. (3) Polygraphus jezoensis und Xyloterus proximus trat als Nachzügler der oben genannten Arten auf. (4) In Sommer-befall kam Monochamus urssovii oft mit ihnen vergesellschaft vor.
6) Verfärbung oder Abfall der Nadeln in der Krone wurde in folgende vier Formen beobachtet (Abb. 2).
Verfärbung oder Abfall der Nadeln schritt (Nr. 1) in der ganzen Krone gleichzeitig, (Nr. 2) in der unteren, (Nr. 3) in der oberen, (Nr. 4) in der mittleren vorzeitig fort. Nr. 1 Form ist normaler Verlauf an den befallenen Bäume. Nr. 2-4 Formen wurden von beschränkten Befall an einem Teil des Stammes verursachtet.

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[in Japanese]

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[in Japanese]

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