A Computer-aided design of forest culture is developed in form of a microcomputer-aided, BASIC program to simulate the design of forest culture for five main timber species in the north of Fujian province. The program includes capability for simulation of growth, intermidiate cuttings and yield, for selection of the proper species and density for a planting site, and for determination of the degree of silvicultural measures and evaluation of site quality. A main-program and five subprogram are produced for APPLE-Ⅱ Computer by the authors. After inputing the data such as site factors and degree of silvicultural measures, the computer can conduct calculations through the mathematics models offered by the authors as well and prints a table of forest culture design. It is expected that the computer design is capable of replacing persons to work for silvicultural alternatives.

Tung-oil tree is one of the important industry oil trees. This article makes a study on the influences of the stand density: on the stand structure of tung-oil trees and the output, in the different conditions of the main tung-oil tree production areas, and on the relation between the density and the stand production quota and the output quota, and on the main elements influencing the stand output. Based on the different stand conditions, the best planting density can be determined by the article and a model of the ideal stand structure of tung-oil trees is developed as well.

The present paper describes two new species of sawflies from China. Acantholyda piceacola causes seriously injurious to Picea crassifolia in Gansu Province and Trichiocampus cannabis to Cannabis sativa in Anhui Province. All the type specimensare deposited in the insect collection of the Forest Research Institute, the Chinese Academy of Forestry.1. Acantholyda piceacola Xiao et Zhou n. sp.The new species is closely related to Acantholyda hieroglyphica Christ., but can be easily separated from the latter by most of mesoscutellum black; only coxae, trochanters and outer sides of femura with black spots; wing vein blackish brown; abdomen in male reddish yellow except for black tergite Ⅰ and Ⅱ; in female brownish yellow except for tergite the hind edges of tergites Ⅶ and Ⅷ which are black.Holotype ♀, Gansu: Zhangye, 24. Ⅵ. 1985, Chang Gui jun leg. Allotype♂, same as for holotype. Paratypes 8 ♀ ♀, 4 ♂♂, sameas for holotype.2. Trichiocampus cannabis Xiao et Huang n. sp.The new species is related to Trichiocampus viminalis (Fallen), but is differentfrom the latter by the following characters: antennae, wing veins, first abdominal tergite, black; costa, stigma brownish black; lancet with about 17 annuli.Holotype ♀, Anhui: Luan, 24. Ⅳ. 1979, Wang Ting kui leg. Allotype♂, same as for holotype. Paratypes 5♂♂, 7♀♀, same as for holotype.

Three kinds of mathematical methods are applied to forecasting the outbreak of pine caterpillar (Dendrolimus punctatus Walker). They are stepwise discriminant analysis, fuzzy preference and figure filtering. Each of these methods has its advantage and fits into difference conditions. The application takes Qinzhou County in Guangxi autonomous region as example and good results are achieved.

The strongest electroantennogram (EAG) response was evoked by Z-9-tetradecenyl acetate (A), Z-11-hexadecenyl acetate (B), Z-11-hexadecenal (C) and Z, E-g, 11-tetradecenyl acetate (D) to the antenna of the male moth of the pine tip moth Dioryctria rubella Hampson (Lepidoptera: Pyralidae). The biol ogical activities of the four compounds in different proportion were confirmed in field tests. The tests showed that the combination of three compounds(B,C and D) is a sex attractant for the male and optimum ratio is 1:7:2 in naturaal rubber septa. The other EAG active compounds A inhibit the effect of trap catch of the B, C and D compounds. Traps baited with the three compounds caught more males than those baited with females did.Male moths were collected in the field with the sex atfractant trap that can monitor populations of the pine tip moth.

Based on the most nearly alike in appearnce, properties, and uses of the wood of Beech familey all the Chinese timber species belonging to 6 genera (Fagus, Castanea, Castanopsis, Quercus, Cyclobalanopsis and Lithocarpus) in this familey can he classified into 15 groups of the commercial woods, namely, Beech, Chestnut, White Evergreen Chinkapia, Yellow Evergreen Chinkapin, Bitter Evergreen Chiakapin, Red Evergreen Chinkapin, Cerris, Prinus (White Oak), Ilex, Suber, White Cyclobalanopsis, Red Cyclobalanopsis, Red Tanoak, Glabrous Tanoak and White Tanoak. Table of the anatomical characteristics and their descriptive key of the 15 groups of the commercial woods mentioned as above were made too.

Pinus koraiensis, Larix gmelini and Larix olgensis are the species of the most important timber in northeast of China. The sample trees of the three softwoods for density and maximum crushing strength test are collected from the various sample plots through out the range of their natural distribution. Some of them had been collected and tested in the fifties, and some sample trees were complemented and tested late. The experimental results of wood are shown in this paper to study the variations in density and strength that may occur not only among the different localities but also among trees within a locality and within a tree.The variations in density and strength of each kind of wood are clearly shown in this research, and thus a reliable representative value (species mean and total variance of wood density and strength.) could be determinated respectively. In addition, the lumber stress grading and grade stresses or characteristic value are derived by different methods in this paper for the structural timber.

The purpose of this review is to provide a generally historical background, current advances and research trend for the taxonomy of the eucalyptus with a emphasis on the introduction to the classification of the genus suggested by Pryor and Johnson.The genus, Eucalyptus L'Heriter consists of some 500 species all of which, but E. urophylla and E. deglupta, occur naturally in Australia and on some Pacific islands in the east of Wallace's line.It has almost been two hundred years since the genus was established in 1788. Many botanists made great contributions to the taxonomy of the genus. At present the new classification suggested by Pryor and Johnson has widely been accepted by botanists, foresters and ecologists both in Australia and overseas. The eucalyptus were in their classification arranged in 7 groups and Angophora, another genus in Myrtaceae, was also included in a equal status to subgenus.The new concept of Eucalyptus alliance was set up by Pryor and Johnson in 1981 based on 8 groups mentioned above. A new subgenus, Telocalyptus, and the monogenus, Arillastrum, were added to their system. there are 10 groups, i.e. Angophora, Blakella and Corymbia in Angophora suballiance, Eudesmia, Symphyomyrtus and Telocalyptus in Symphyomyrtus suballiance, Gaubaea, Idiogenes and Monocalyptus in Eucalyptus s. str. suballiance, under Eucalyptus alliance. There is a trend now in the research on the taxonomy of Eucalyptus in Australia that may make these 10 groups independent as genera in the future.

This paper discusses the formula P_n=P₁/n² (q.v. printed in the textbook of Forest Measurement (P.16-18)published by Beijing Forest College, 1984)and points out that the above formula is incorrect. Its right formula according to author's opinion should be P_n=P₁/n². The author gives his reasons that the deviation of the calculated volume of a felled tree is decreased with increasing in the number of sections and is increased with increasing in the-taper of a stem(q.v, the equations (9), (11)).

This paper, in terms of the data (1980-1983) of the four large forest areas: Da Xing-an Ling, xiao Xing-an Ling, Zhang Gangcai Ling and Chang Baishan, draws the following conclusions by the statistical results of random sampling of logs on the longitudinal, sorting conveyor:1. The current distribution law of the linear load on the sorting, longitudinal conveyor at log yards is "The Curve Distribution of K. Pearson Ⅲ"2. If given the confidence probability which is 90%,the credible ranges of linear load on the sorting, longitudinal conveyor of the four large forest areas are following respeetively: Da Xing-an Ling: q=0.0031—0.072z; Xiao Xing-an Liny:q=0.0040—0.1369; ghang Guany-cai Ling: q=0.0043—0.1739; Chang Bai—shan: q=0.0031—0.1338.

This article approaches the process of cultivation of artificial timber stand and introduces a new concept Cultivability from the principle of economics and silviculture. It points out that the output value of silviculture of artificial timber stand should be divided into two parts, the output value of stumpage and the output value of cultivability. A statistical method of calculating output value of silviclture is develop ed, with regard to forest compartment asa basic unit and deals with the classifications of forest sites. The use of this method is able to make the calculation of output value of silviculture more rational and accurate and eliminate influences caused by some natural factors so as to improve the comparability of output value indexes.

Since 1955 Mongolian pines have been introduced and planted on the sand land of Zhanggutai District. They shows stable performance and quick growth in general. Water content in the plant-root-layer of soil tends to descrease. In arid years, the growth and development of the trees are seriously affected. If the precipitation decreases by 10 mm., the tree height reduces around 0.5—15cm and the D.B.H. reduces 0.034 cm. Drought causes the needle to fall early than usual and also decreases the intensity of transpirat'on and photosynthesis of the trees, but, promotes fruit setting.

Natural resources of dove trees (Davidia involucrata Bali) are rich in Guizhou province, China. Especially in Fanjingshan Mountain Reservation, there is a primeval forest community of dove trees distributed over the area of Heizhan, from 1,000 to 1,800 metres above sea level. In this paper the authors point out that the species composition of the dove tree forest is compartively complex,and mixed by both deciduous and evergreen trees. The importances of dove trees in ecology and resource conservation are discussed as well.

Schlechtendalia chinensis (Bell) is the most important gall-aphid made of Chinese gall-nuts in the world. The output of Chinese gall-nut caused by Sehleehtendalia chinensis (Bell) is directly related to the number of the insect migrating from the secondary hosts or overwintering hosts, mosses belong to the genus Mnium Hedw, to the primary host (Rhus chinensis Mill) on which the galls are formed, but the patterns of the migration of the spring migrants is not yet known. Therefore, during these two spring seasons in 1984 and 1985 some observations were made and the results are as follows:1. The migration period takes 23—32 days, but 70—80 per cent of the migrants fly out of the overw,intering hosts within discontinuous 3—5 days. The peak of migration is only once oneday, with its appearance at13—16 o'clock.2. For the most part of the migrants fly from overwintering hosts in sunny days with higher temperature, a few in cloudy days, none in raining days.3. Temperature is the most important climatic condition for migration which does not oecure below 10℃ with the optimum temperatureover 15℃.4. The migrants are not active if the mosses are wetted. The optimum humidity is below 80%. It is not favorable for the migration when the humidity is over 85%.5. Sunlight and lamplight from one to forty thousands Lx may cause its flying with the direction towards the stronger illumination.

The ant, Polyrhachis dives, is a social insect which lives in a colony often consisting of thousands of individuals. Each colony contains three types. These are the female, the male and the worker. "Females are large, 8—10mm. long. Males are smaller, 7—8mm. long. Workers are of various size, 5.5—7mm. long. Eggs, larvae, pupae and adults can be found in the colonies thrcughout the ycar. Winged females are produced in fall and winter. They nest in trees, shrubs or herbs. Nests are irregular inshape, about 10—39mm. in length and 6—20mm, in width. They feed on insects, honey, honeydew and other sweet glandular secretions of plants. Aphids and coeeids are insects living in symbiosis with them. Some factors that influence their population development were studied. They can play a certain role in the control of Ist-2nd instar larvae of Dendrolimus punctatus in forests.