PS Ⅱ electron transport activities, chlorophyll and carotenoids content, SOD activities and isozymograms of needles from shaded and exposed seedlings and trees were monitored on Changbai Mountains during winter 1987-1985 to illustrate the internal protective mechanism of Korean pine (Pinus koraiensis Sieb. Et Zucc.) trees against winter photo-oxidation damage. The results show that the inhibition of photosynthetic capacity measured as PS Ⅱ electron transport rates are nearly as deep as solarexposed seedlings, but trees accumulated more chlorophyll and carotenoids in autumn can maintain higher contents in winter. SOD activities show higher activities in trees than those in solar-exposed seedlings as well. However, no extra isozyme bands are showed for trees. The data indicate that the mentioned substances may be synthesized by needles during soil frozen period. The possible role of SOD as free-radical scavenger in cold resistance is discussed.

The most important problem in the afforestation with Pinus sylvestris var. mongolica is physiological drought. Some provinces have adopted the method of "burial in soil" to prevent this phenomenon. But the method has three shortcomings: hight cost; liable to damage the seedlings; difficulties in grasping proper time. During the research and experiments in eleven years (1975—1987), a new technique was explored: Planting seedling near the southern wall of a deep hole and burying it with soil. This technique can create a favourable microenvironment for seedlings without wind and direct radiation but with more moisture because the seedlings are snow-covered and moderaely grass-covered for a long time. The success in the afforestation with Pinus sylvestris var. mongolica in 2660ha and the results of the simulated tests show that the new technique has good effect on preventing physiological drought of P. sylvestris var. mongolica in the northern China.

The 26 origins of Pinus armandi were used as the test materials. The inheritance and character variations of the 8 years old juvenile forest were analysed. Through the researches, we found out that there were significant differences among different provenances, and there was notable linear correlation between the majority of the characters and the latitudes in their original places. Pinus armandi shows a latitudinal decline. The provenance of Yunnan-Guizhou Plateau grows faster; its biomass yield is high and its needles are longer and are in small density. The provenance of Qinling-Dabashan Mountains is on the contrary. The leading factor of the variations is caused by the extreme temperatures of the original places of Pinus armandi.

The relationships between the characters of the 2 years old Platycladus orientalis (L.) Franco seedlings from 56 provenances and the climatic factors in their original regions were studied by using the method of canonical correlation. The results show that (1) the correlations between the number of branch, female flower and the annual precipitation are significant; (2) the number of male flower is related to the annual mean temperature especially the mean temperature in January besides the annual precipitation; (3) the value of weights to "Overfell tallow" is great among the factors of the first two canonical variables. In favor of indirect selection, "Overfell tallow" is a character to which attention must be paid. Moreover, the map of cluster points was drawn on the basis of the weights between the climatic factors and the biological factors of the canonical variable 1. 3 ecotopes and 7 ecoplots were classified in accordance with the map of cluster points. Consequently, the climatic characteristics of the ecotopes and the growth situation of their ecotypes were summarized.

Two compounds, Z₅—C₍₁₂₎OAC and Z₅—C₍₁₄₎OAC were found in the washings of female ovipositors and sex pheromone glands of the Cossus mongolicus Ersch. through comparative analysis with capillary GC and GC MS. Among the two compounds only Z₅—C₍₁₂₎OAC caused strong EAG response of the male Cossus mongolicus Ersch. and showed obvious attraction in the trapping tests in two years and potential use for this pest control. The results testified that Z₅—C₍₁₂₎OAC was a major sex pheromone component of the Cossus mongolicus Ersch.

The paper is on the basis of measuring statically spatial pattern using six indices of distribution pattern. By cluster analysis, horizontal and vertical pattern in the course where Dendrolimus tabulaeformis larvae go up pine trees may be classified into two types of early and middlelate phases. The six indices were classified into three kinds: (1) m^*m, C_A, I_δ; (2) λ; (3) C, L. The cluster analysis can take out more information than using probability distributions to fit the statical pattern or only using single index for that purpose. Obviously there is practical significance in sampling decision.

This paper gives a detailed analysis on the regularities and causes of the quantitative changes of Pinus tabulaeformis caterpillar Dendrolimus Tabulaeformrs population in the western Liaoning province. A life table about the population was drawn, and approaches forpine caterpillar control were put forward.Improvement of forest ecological environment is tonsidered as longterm strategy while through control as short-term strategy.

Three trees of Pinus tabulaeformis Carr. Were collected from a natural stand of Zhongtiao Mountains in Shanxi Province. From pith outward, the tracheid length first increases rapidly, then increases slowly after 13 years old, and levels off after 20 years old. Along the stem height, the tracheid length increases progressively from the base upward, maximum at 5.3m in height, and then decreases to the top of the tree. The shortest tracheid length was found near the crown of the trees. With augmenting age of formation of the cambial initials, the length of these cambial initials first increases, and then decreases. The tracheid diameter and the thickness of cell wall increase from pith to bark. From the base to the top of the tree, the tracheid diameter increases step by step, then decreases near the top of the tree. The radial variations of the tracheid length-width ratio and tracheid wall thickness-diameter ratio are similar to the variation of the tracheid length. Within a growth ring, the tracheid length decreases gradually from spring wood to summer wood, and then increases quickly. The tracheid length of the spring wood is shorter than that of the summer wood, and the minimum of the tracheid length is at the transitional position of the spring wood and summer wood.

Methods of quantitative characterization of wood color were briefly reviewed. 22 Chinese common wood species including both softwoods and hardwoods were selected for wood color measurements according to CIE (1931) and CIE (1976) (L^*a^*b^*) systems. Results revealed that color parameters of different woods or samples were not very much comparable unless the method of measurement employed and the measuring conditions were exactly the same. The difference of wood chromaticity co-ordinates among species were greater than within species. Although wood color differences among species exhibited both in luminosity and chromati city to a certain extent but within species significant variation mainly exhibited in luminosity.The shapes and tendencies of those curves for reflectance of wood surfaces against wave-lengthes were found very similar both among and within species. In general, the wood color of those species tested exhibited some significant variations but they had certain regularities. So it seemed possible to simplify the color spaces by means of the principal component analysis, a method in mathmatical statistics. Comprehensive parameters were obtained and two empirical formulas were thus established. Preliminary tests for these formulas proved quite reliable. For the convenience of directly perceiving the wood color, Munsell color notations were also given in addition to the CIE parameters.

The drought resistance of several silvicultural species have been determined and analysed in the aspects of growth, physiology and anatomy, passed a judgment on their drought resistance by using complex indexes. The results indicate that Arborvitae and Chinese pine are the best drought resistance among the tree species, Mongolian Oak and parple blow maple are the second one, Black locust is poor in comparison with other tree species. In shrub species, common smoketree, common seabuckthorn and little leaf peashrub are relatively drought-resistant, while shrubby labseindigo is rather poor resistant to drought.

China has large areas of Saline-alkah Soils, for which many breeding specialists including forest breeders and crop breeders have been being engaged in the breeding of saline tolerant plants. The experiment was conducted to induce the saline tolerant mutants in use of poplar callus line. In the experiment, MS was the basic culture base,2,4-D,NAA and BA were used as additives. Under a proper proportion, large numbers of embryoids or multiply shoots from some pieces of the leaves were induced. Later, these multiply shoots were induced in to the culture base with additive of NaCl. The increase gradient of NaCl. content was 1.5-3%. Totally, the subculture was continued for eight times. For each time, it was 30 days. Complete plants were formed from multiply shoots growing in the MS with 12.5% NaCl content.In the process of physiological inducement of saline tolerant mutants, explants demonstrated different degrees of tolerance as in the order of yellow leaf, indifferentiation of root organs, inhibition of root system development, normal growth of root system, and complete plant with good growth. The mutants not only increase the saline tolerance, but also produce an obvious variation of morphology and isoenzyme spectrum of peroxidase enzyme.Different poplar species showed different reactionsin the inducement process. Saline tolerant (content 12.5%) mutants could be induced for Populus nigra, P. × beijingenses Cl '8000'. For P. diltoides Cl 'lux' and P. catheyana the root organs only could not differentiate. For P. maximowiczii, P. ×uramencana C1 'cima' and P. Popularis C1 '36' explants died as the NaCl content increased to 9%.

A hedged orchard for cutting production of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook. ) occupying 0.80ha. Has been established since 1986. 31, 000 seedlings originated from desired provenances, families and seed orchards were planted in the orchard as donors. The orchard is unique to the existing ones found in the literature due to the fact that no main stems can be seen, while shoots come up from the stems lying underground and are also collected from the cuttings underground. Experiments showed that the number of the cuttings produced in 1m~2 of the orchard area was about 270 in the second year and 470 in the third year of the establishment. This means that the number of the rooted cuttings yielded in a given hedged orchard area is double or even triple the number of the seedlings produced in the same area of a seed orchard at the highest yielding age of 10 years.An average of 90% rooting survival rate in practice was obtained with no shading, no irrigation and no hormone treatment. No damping-off disease was found. Both average height and diameter at the root collar were larger in the rooted cuttings than in the seedlings of the same age. About 230 000 rooted cuttings, whose expected genetic gain would be equal to that of the original stocks were produced in the past two years, and 600 000 propagules are now growing in the nursery beds. The cost of a rooted cutting was 20% lower than that of a seedling.The techniques for cstablishing a hedged orchard, and the efforts to obtain high yields of shoots and to reduce the cost are also recommended in this paper.

Starting with the analysis on the correlation among tree species, this paper established the criteria for qualitative determination and differentiation of correlation among tree species, and quantified the norms of qualitative determination. Hence the criteria for the selection of tree species for building mixed forest were obtained. These methods are feasible and have guiding significance in practice through practical tests.

This paper is studied the inoculation for development of ectomycorrhizae on container-grown tree seedlings of some commercially important Chinese tree species with two different types of inocula of the ectomycorrhizal fungus Pisolithus tinotorius (P_t). Results show that the inoculation of these tree species tested is successful with solid-base cultures of mycelium of this fungus. Excellent P_t, ectomycorrhizal root de velopment (P_t index 70⁺ and P_t ectomycorrhizal percentage 95%) is produced on the seedlings of the four pines tested. The typical (large, swollen, golden, bifurcate) P_t ectomycorrhizae observed on these four Chinese species are identical to those observed on Loblolly Pine. It confirms that like Loblolly Pine these pine species are hosts of P_t fungus and implys that there is a great potential to use the techniques for development of ectomycorrhizae on these species in forest production. However, spore pellet inoculum is considerably less effective (P_t index 10 and P_t ectomycorrhizal percentage<20%). No ectomycorrhizae on Chinese Fir, Chinese Arborvitae and Siberian Eim are observed in this experiment. This suggests that these species most likely are endomycorrhizal or/and facultative ectomycorrhizal tree spectes. Besides, this study also provides techniques and methods for development and evaluation of ectomycorrhizae on container-grown tree seedlings for forest research and production in China.

Six species of fossil woods have been excavated from the Dabie Mountains. Three of them excavated at the southern foot of the Dabie Mountains in Hubei Province have been identified as Cunninghamia lanceolata Hook.,Cupressus(nomen idterminatum)sp. Nov. and Ormosia pinnata Merr. from the Late Tertiary Period, which proved the hot and humid weather during the period. The other three excavated at the northern foot of the Dabie Mountains in Heaan Province have been identified as Podocarpus nagi Pilger, Keteleetia fortunei (Merr.) Carr. and Pinus (nomen idterminatum) sp. Nov. from the Cretaceous Period, which confirmed that the weather at the northern foot of the mountains was colder and drier than that at the southern foot.

This paper discusses the low vibrational measures and the tests which have been made on the two types of the Chinese high-handled chain saws. We have drawn up many curves on studying the chain saws. These curves are: the time course curve of acceleration, the curve of power chart, the curve of the relationship between the vibrational acceleration and the rotational speed and the curve of the vibrational acceleration in different frequencies.In this paper, we also made preliminary analysis on the vibrational course, the vibrational characteristics and vibrational regularity of the chain saws.