In fir forest of west Sichuan, several aspects of forest hydrology have been observed: Interception of precipitation by canopy, water retaining capacity of mosses and litter, variation of soil water content, evapotranspiration of vegetation cover and the flow of two comparative catchments of forest and cutting site. It shows that the fir forest has very important influence on regulating the water regime and higher water holding capacity, including increasing annual runoff, decreasing and slow down the flood peak, increasing the utilization of effective water regime and reducing the physical evaporative capacity.Abound with water-heat and light conditions in fir forest area of west Sichuan, very suitable for the development of vegetation. Meanwhile, the structure of the forest stand and the tree species indicate that most stands are overmatured forest (over 200 year) with low water regime comsumption. So, it cannot raise the timber yield by fully using water resources and improving the hydrologic influence. According to the reference of other countries, the water regime comsumption of pine tree is about 208mm, larch: 220mm, spruce: 193mm, while the fir forest request the lowest water comsumption among coniferous forests. According to our estimation the annual evapotranspiration on fir forest is quite low, occupied only 5% of the annual precipitation. Meanwhile, under existing physical conditions,it was suggested that using coniferous of high growth rate such as larch or spruce instead of the overmatured fir forest gradually. This may be of benefit both to raising the timber production and improving the hydrologic influence of the forest. For better conservation of the enviroment of the forest land, selecting cutting or sanitary cutting may be practised and the forest may be regulated by the other species with high growth rate and good hydrologic influence.

Based on the research of Pinus koraiensis seed bank, the paper has studied on the pattern and its dynamic of Pinus koraiensis seedling and sapling distribution; Pinus koraiensis population age structure in juvenile stage and the relationship between juvenile Pinus koraiensis and their environment. Near one thousand quadrats of 4m² and 7 plots of 20×20m² were investigated, 388 seedlings and saplings were measured concerning biomass and age. As a result the process of Pinus koraiensis natural regeneration and the mechanism of "regeneration complex", it says that the Pinus koraiensis natural regeneration can be carried out under the broad leaved forest, have been discussed. The research is important to reveal the self maintain process of Pinus koraiensis, an ageold population.

Chinese fir (Cunninghamia lanceolata (Lamb.)Hook) seedlings were raised from seeds and grew in pot culture at six levels of N (urea) supply: 0.0, 0.4, 0.8, 1.2, 1.6 and 2.0gN/pot. The results of the trial are as follows: 1. With increasing levels of N supply from 0.0 to 1.2 gN/pot there were greater height, stem basal diameters, dry weight of leave, stem, root and seedling, numbers of shoots, total lengths of shoots, chlorophyll contents, net photosynthesis rate, respiratory rate, photorespiration rate of seedlings, while with increasing levels of N supply from 1.2 to 2.0gN/pot all of the items decreased. But with increasing levels of N supply there were shorter lengths of roots. 2. There were highly significant positive linear correlation between dry matter weight and net photosynthesis rate, respiratory rate of seedling. And there were highly significant negative linear correlation between dry matter weight and photorespiratory rate of the seedling. 3. With increasing levels of N Supply there were greater total N concentrations of roots, stems, leaves. 4. If the concentration of leaves were in the sub- optimum rangs there were significant positive linear correlation between height, stem basal diameters, dry weight of seedling, net photosynthesis rate, chlorophyll contents of the seedlings and N concentration of leaves, but if the N concentration were in the superoptimum rangs there were significant negative linear correlation.

The element content of N, P, K, Ca, Mg, Cu, Fe, Mn and Zn, in the leaves of every each tree species (including Pinus tabulaeformis, Platycladus orientalis and Acer truncaturn) in the plantations was studies lasted three years (1983—1985) in this paper.The result shows that the content of each element in the leaves of different trees growing under different site conditions is quite different. The content of each element in the leaves of the maple (Acer truncaturn) is very rich and it is much richer especially under suitable site. Therefore, the maple is a good associated tree species which is suitable for growing in the mixed stand together with the pine. The annual and seasonal variations of the content of each element provide basic materials for forest fertilizing and tending.

In this paper, a new genus of Tenthredinidae from China is described and the type species is redescribed based on the holotype, allotype, and additional specimens collected in April 1983 in Changde Prefecture, Hunan Province. All the type specimens of the type species are deposited in the Forest Research Institute, The Chinese Academy of Forestry.Dasmithius Xiao, new genus Type species:Caliroa camelliae Zhou and Huang, 1980.Description: Antenna 9-segmented, filiform, length about 1.5x head width; Ist segment longer than broad, 2nd segment about as broad as long, 3rd segment slightly longer than 4th segment, apical 4 segments reduced in length compared to previous segments. Clypeus nearly truncate; very shallowly and broadly circularly emarginated without narrow lateral teeth (figs 4, 5); mandibles symmetrical, each with a subapical tooth; malar space about 2/3 diameter of front ocellus; occipital carina present, distinct to top of eyes; eyes prominent, slightly converging below, lower interocular distance greater than eye length; head from above slightly narrowing behind eyes; lateral sutures wide and deep, straight and parallel; postocellar area convex and wider than long; antennal furrow wide and shallow; frontal crest absent. Abdominal terga without paired white spots. Hindbasitarsus as long as remaining tarsal segments combined. Tarsal claws bifid, apical tooth longer than subapical tooth, with small basal lobe (indistinct but can be seen after dissection) (fig. 2). Forewing with 4 cubital cells; cell 2Rs as long as cell 1Rs at least along vein Rs; anal crossvein strongly oblique; veins M and lm-cu parallel; veins M and Rs+M meet Sc+R at same point. Hindwing with cells RS and M absent, petiole of anal cell slightly shorter than greatest width of cell, crossvein cu-a perpendicular to veins above and below, male without peripheral vein. This new genus belongs to the subfamily Allantinae and is near Malachiella Malaise in Malaise's 1963 key, but it is distinct from the latter by the nearly truncate clypeus(very deeply and narrowly circularly emarginated with narrow lateral teeth in Malachiella), and the presence of the occipital carina to the top of the eye (absent in Malachiella). The combination of the characters above should distinguish Dasmithius from all other Allantinae.Distribution: China. Dasmithius camelliae (Zhou and Huang), new combinationFemale: Black, shining. Antenna black; labial palpus dark brown; apical 3 segments of maxillary palpus brown; hind margin of pronotum, tegula, and cenchri whitish yellow; coxae and femora black, troehanters white, tibiae and tarsi brown. Wings subhyaline with yellowish lustre; stigma black with base yellowish; most veins blackish brown with veins M+Cu₁, Ci₁,, and M black.Antenna slightly compressed apically. Postocellar area rather convex, width 0.50mm, length 0.37mm; frontal crest absent; lateral sutures and transverse suture distinct; middle fovea deep and distinct; OOL:POL: OCL=61:29:51. Clypeus with coarse punctures; frons and ocellar triangle without distinct punctures, rugose; punctures of orbits, postocular area, and thoracic dorsum fine and sparse; abdomen without punctures. Clypeus, frons, orbits and prothorax with long whitish-yellow hairs; wing membrane with many black hairs. Sheath nearly uniformly slender in dorsal view, rounded in lateral view (Fig. 6, 7). Lancet Well sclerotized with 16—17 annuli (Fig. 1).Body length, 6.5—8.5mm; 3rd antennal segment. 0.66mm; 4th antennal segment 0.57mm; antennal segments 4+5, 1.10mm.Male: Color similar to female except lateral parts of hind margin of pronotum yellowish white; tegula blackish brown; legs with pale parts more dark or blackish brown. Body and legs with denser hairs. OOL: POL:OCL=51:29:53. Body length, 5.8—7.5mm; 3rd antennal segment, 0.74 mm;4th antennal segment 0.59mm; antennal segments 4+5, 1.28mm. Other characters as for female. Penis valve as in Fig. 3.Host plant: Camellia sinensis (L.)Habit: This species has one generation a year and overwinters as a prepupa in the soil. Adults emerge in the spring and deposit eggs in the newly sprouted leaves of the host. The larvae feed on the leaves and very serious damage may occur during outbreaks of these pests.

In the present paper, a new ant of the genus Gnarnptogenys is described.Gnarnptogenys sinensis n. sp. (figs. 1—3)Worker: TL 6.9mm; HL 1.57mm;HW 1.52mm;CI 96; head length with mandibles 1.97mm; scape length 1.59mm;greatest diameter of eye 0.16mm; petiole length 0.50mm.Head almost perfectly straight and parallel sides and the rather sharp occipital angles; the occipital border distinctly concave; antennal scapes a little beyond the occipital angles; antennal funiculus stout, segments 4—10 as long as broad, the remains longer, without a club; clypeus with a very distinct sulcate in the middle; mandibles indistinctly denticulate. Thorax seen from side round dorsal surface,with the promeso and mesoepinotal sutures distinctly, but not emarginate; the humeri of the pronotum with stout, prominent and obtuse angle, forming a pair of teeth. Coxal tooth subeonieal, with a broad base; middle and hind tibiae each with a single slender pectinate spur; all tarsal claws with a single extra subb asal tooth. Petiolar node parallel at the sides and posterior border, slope down in front, and round above, much broader than long and a little broader than high.Mandibles smooth, shining, sparsely striated; clypeus longitudinally striated; the rest of head, pronotum and mesonotum coarsely punctured, with the noticeable development of the longitudinal striations between punctures;epinotum, the node of the petiole and the first gaster coarsely punctured, cribrate; the remains of the gaster smooth and shining, with a few indistinct punctures. Pilosity yellow, rather dense, short and thin covering the whole body.Color dark ferruginous brown; the front of head, sides of thorax, and gaster more reddish; antennae, legs, mandibles reddish brown; the apical segment of gaster more yellowish.Holotype: Daoxian Co. of Hunan Province, 30 Ⅷ 1982, Tong Xinwang leg.; Paratypes: 5, same data as for holotype. All the types are deposited in the Insect Collections of the Forest Research Institute, the Chinese Academy of Forestry, Beijing, China.This is an unusual species of the shape of the humeri of thorax, and easily distinguished from other oriental species of Gnamptogenys of which I have seen the. Species and descriptions.

This paper deals with the biology, morphology and ecology of a barconid wasps, Ontsira palliatus (Cameron), ectoparasitic on the larvae of Semanotus sinoauster (Gressitt). Other aspects concerning this wasps are also discussed including its distribution in China, methods of reproduction, range of hosts and controlling pests in large area, etc. It is for the first time discovery that Semanotus sinoousteris parasitized by Ontsira palliatus. In China fir (Cunninghamia lanceolata) wood, the percentage of parasitization of Semanotus sinoauster at the contemporary generation is about 70—80% after artificial release, and that of actual control effect is about 90% Ontsira palliatus has great capabilities of looking for host, spreading over rapidly and controlling hosts on a large scale. Therefore, it is much better to adopt the above mentioned parasitic wasp as a biological control agent than to use the chemical insecticide of carbofuran for preventing Semanotus sinoauster from China fir woods, Because the former saves a lot of labour, and is simpler and more effective than the latter.

Chinese-pine caterpillar (Dendrolimus tabulaeformis Tsai et Liu) was used four testing the developmental threshold and effective accumulated temperature of its different life stages and instars by means of linear regression method, the method of coefficient of minimum variation and the direct optimum method under varying temperature of laboratory conditions. Through computation and data checking, the authors found out that the theoretical number of generation is fundamently in coincidence with that actual number of generation. It was found there was only one generation per year. Among these three methods, the direct optimum method seems to be the most concise and accurate one.

This article presents theoretical analysis of the grabing force of a log grapple and the force function acted on the grapple's jaw through experiments, it creats the grabbing force formulae under two different working conditions (grabbing compact logs pile and bundle-like logs pile). The tests prove that the formulae are acceptable and three kinds of force functions acted on jaw are developed in the paper. The tests also prove that one of the force functions acted on jaw is parabola distribution during grabbing compact logs pile, the other is sine curve distribution during grabbing bundle-like logs pile.

To characterize the process and mechanism of the CRT dryig schedule two common species of Chinese commerical timbers (Pinus koraiensis and Fraxinus mandshurica) were used for trials in an experimental drying kiln. Results revealed that CRT and Medium-High Temperature (MHT) drying schedules are both significantly effective in reducing the drying period without any additional degradation percentage as compared with the conventional kiln drying schedule. Furthormore, there were no detrimental effects on MOR、MOE as well as on toughness, except shearing strength which was found 10% less than timber dried with the conventional schedules.The drying qualities including the wood strength properties were evaluated with a result almost equivalent to those dried with MHT schedule, and the drying period was shortened to some great extent. In this experiment P. Koraiensis timber was found more suitable for CRT drying process than F. mandshurica wood.Some schedules were proposed for further consideration and trials.

China is the distribution center of walnuts (Juglans). The most important species of this genus native to China is Juglans regia L., the persian walnut, grown throughout 18 provinces of China. It has been suggested that cultural seedling population of Juglans regia L. may be divided into 4 geoecotypes (Xin Jiang, Northern Mountain, Qin and Ba Mountain, Xi Zang Highland) The origin, geographical distribution, ecological characters and main seedling groups of 4 types are discussed. The precocious seedling group of Xin Jiang walnut is valuable in genetic improvement of potential productivity. According to the preliminary result of progeny test, it was considered that precocity is a dominating character controlled by at least 2 genes. The Northern Mountain Walnut seems more resistive to some diseases (Xanthomonas campestris pv. juglandis,). The hybrid seedlings of J. regia L. × J. mandshurica are evaluated as walnut rootstock and rootability of cuttings collected from some seedlings incressed.

Since 1958, large area of Yunnan pine forest have been established by aerial sowing in Liangshan prefecture, Sichuan province. Due to the interference made by deviation flow during aerial sowing, large stripes of land were either left out from sowing or sometimes sown repeatadly.This paper tried to made an exploration on the method of revising flying direction to overcome deriation flow in areial sowing. Astrict and correct methematical equation for this purpose has been worked out. If put the equation into programming, we can get the correct revised value of flying angle quickly so as to avoid deviation flow to guarantee and improve the quality of aerial sowing.

It was found that the value of instantaneous plastic deformation of poplar in compression perpendicular to grain is not proportional to the value of constant stress under the conditions of a wide range of the constant stress, various temperature, moisture content, and the specimen with or without water vapour passing through them, because there exist two turning points in general. The beginning point of the time-dependent plastic deformation makes considerable influence on the mechanical behaviour in a short time. When the condition of the specimen falls in the range before the first turning point, the viscoelastic deformation would be much more considerable than the plastic deformation in a short time because of the slight instantaneous plastic deformation and the later beginning point of the timedependent plastic deformation.

The water relations in saplings of Populus deltoides Bartr. cv. "lux" (ex. I-69/55), P.×euramericana (Dode) Guinier cv. I-214, P.×euramericana (Dode) Guiniercv. Sacrau-79, P.×opera Hsü and P. popularis Hsü were studied during the winter season in 1980—1982. Five poplar clones were classified into three groups according to the determinations of their monthly water contents, water saturated deficits, transpiration rates and diurnal and monthly changes of water potencials in the branches. It was find that, three clones from section Aigeiros included group Ⅰ-Populus deltoides Bartr. Cv. "lux" (ex. I-69/55) and group Ⅱ-P. ewamericana (Dode) Guinier cv. I-214 and P. euramericana (Dode) Guinier cv. Sacrau-79 have lower water content, transpiration rates and water potencials and higher water saturated deficits in branches which than other two clones from section Tacamahaca included group Ⅲ-P.×opera hsü and P.×popularis hsü. The result showes that water stress during the winter season is the main reason of lower survival rates in transplanting of poplar clones from group Ⅰ and group Ⅱ.

According to the concept of turbulivity, this article using the data of earth surface temperature, air temperature and wind velocity from the National Weather Station have calculated the turbulivity and found the relationship between the factors of forest fire hazard and the numbers of the forest fire occurred. The result shows that the turbutivity one meter above the surface has the positive corelation to the forest fire hazard.The results of the calculation can also be used as a indicative signal of forest fire.

Hegesidemus harbus Darke (Hemiptera: Tingidae) is one of the most dangerous pests, it is increasingly injuring "I-45", "I-72", "I-69", and "I-214" new Poplar clone.Both the adult and the nymphs feed on the back of leaves, causing the appearance of small whitish bleached areas on upper surfaces of the leaves. The Tingids produce a large quantity of excrements which become the medium of black sooty molds. While infested seriouly, all the leaves begin to turn yellow, resulting in the damaging effect to the growth of poplar.The Tingid has 4 generation a year in Shandong, China. The adults overwinter preferably in bark crevices and under leaves which fall down on the ground of poplar stands. They also overwinter in the crack of land.The adults emerge in late April to early May of the next year, when the mean daily temperature is at 11-12℃. The eggs are laid on the underside of the leaves adjacent to the veins. The adult and the nymphs feed gregariouly on leaves. The symptoms of infestation appear from the lower part of the tree to the upper part of it.It is promising to use 80% Dichlorvos, 40% Omethoate, and 50% Monocrophos to control the pest. Silvicultural method is effective for controlling the pest. Use and protect natural enemies is also recommended.