From field investigations and inoculations, Dothistroma pini, the pathogen of Dothistroma needle blight was found to overwinter as mycelium and unmaturcd acervuli in infected needles. The conidia were spreaded mainly by rain splash. The disease became widespread by transporting diseased seedlings and scions, conidia spread throughout the growing season, but mainly from May to July. The disease was found in both stand locations in each summer of investigation. The outbreak severity was serious in pure stands of susceptible pine and mixed stands with large components of susceptible pine, but slight in mixed stands of unsusceptible species with small components of susceptible hosts. The disease was less severe in pruned stands than in unpruned stands. The disease was most serious near the infection centre, indoor and outdoor tests, it was shown that Chlorothalonil smoke, Chlorothalonil spray and Thiram and Asomate sprays were effective control fungicides.

Predetermination of growth ring wood quality was a frontier. By the method of growth ring wood quality analysis, correlation ship of variation between the wood quality and ecological condition of forest growth is explained with the theory of quantification. According to index of quantification model, the variation of forests growth and wood quality is forecasted.This paper discribed the correlationship between branch wood and stem wood of growth ring wood quality, according to quantification index to infer the stemwood quality by the branchwood quality predeterminning stemwood quality, this lead to a new way for wood quality predetermination.

The resin content in larch wood is usually determined by the traditional Benzene-Alcohol Extract Method (BAEM). In order to meet the requirement of production practice, the authors present two simple quick determination methods, IR lamp method and hydrogen peroxide solution method. Compared with the results of traditional method, the results of new methods are nearly the same as former, therefore, both two methods can reflect the change condition of resin content in wood.

In this paper we used the finite element method (FEM) to predict case furniture deflection. We dispersed and analyzed furniture which made of particleboard by elastic plate elements. The corner joint of case furniture is a key problem during the calculation by FEM. We assumed that small elements which located near corner joints were semi-rigid elements. Then we obtained the fabricated modulus of elasticity of the semi-rigid elements by individual corner joint experiments. We used four kinds of particleboard and two kinds of corner joint forms to make up eleven cases. The displacement of some typical points under each load measured by the Furniture Strength Test Machine. Then we compared the displacements of measurements with that of calculations, the errors were usually within 30 percent. Results of this study indicated that the deflection of case furniture could be calculated by using FEM, and proved that the program could be used for predicting case furniture deflection reliably.

The working processes, machining devices and tools, cutting amount, consumption of materials, productivity and quality of products are directly affected by wood surface roughness. This paper gives an extensive review of methods used previously to measure wood surface roughness, and concludes that computer vision is the most suitable technique. The preliminary study shows that computer vision method has the advantages of a noncontact, three-dimensional measurement, high speed and well correlates with stylus tracing method. This method can be used in classification and in-time measurement of wood surface roughness after being improved.

The sulfate soap is refined through extracting unsaponifiable neutral substance using ethyl acetate and hexane-acetone. The content of neutral substance in tall oil decreases from 32.8% to 17.4% and 18%. The acid number of tall oil increases from 119 to 169 and 153. The quality of tall oil is greatly improved. This provides a favorable condition for distillation of tall oil. The unsaponifiablc neutral substance from crude sulfate soap mainly consists of terpene aldehydes, terpene alcohols, fatty alcohols and sterols in which larixol is 26.3% and 18. 5%, sterols are 17% and 27.1% separately. The white crystals containing sterols of 96.9% are obtained by crystallization and recrystallization. The sterols are mainly β-sitosterol and campesterol.

The slurry scaling with cationic emulsified asphalt, which is a new technique in highway construction, is rapidly extended at home and abroad. The technique should apply an excellent slow set cationic emulsifier. Now, slow set emulsifiers are ligninamines which are synthesized by trimethylamine-epichlorohydrin route. Owing to high price and unstable quality, the extending of slurry scaling technique is affected seriously. We prepare the ligninamine by a novel synthetic method. By the novel method, the cost of production is reduced by more than 30%, and the products have stable quality, high emulsifying function and broad adaptability for various asphalts. The novel synthetic method uses soda lignin, secondary amines and inexpensive aminating assistants as raw materials. The technological process of the method may use either one or two-step process, and the technological condition are uncomplicated and easy to master.

Through the content analysis of nutrient elements in the soil and in the needle at the different site classes and periods of growth ofP. koraiensis, and in a single growing season, some conclusions can be drawn below: Most of the soil nutrient elements were higher at the good sites than at the poor ones in an annual average concentration of them, i.e., site class 1 > site class 2> site class 3. And forP. koraiensis tree at every site class, the nutrient elements in their needles did the same. However, each of the elements in the soil or in the need was seldom at the same level of concentration on the good or on the poor site during different periods of growth. There are no an inevitable relationship between the contents of the soil nutrient elements and the needle’s. And whether these elements are high or low within a tree body may depend on the physiogical requirement of the tree, but not on their contents in the environment. Some nutrient elements required forP. koraiensis varied with growth periods during a whole growing season. N, P and K, for example, were greatly needed only at the fast growth period, while Ca at the initial growth period; and on the contrary, Ca was needed less at the fast growth period. In intensive forest management, therefore, fertilizers with N, P and K should much be applied at the fast growth period, while fertilizer with Ca at the initial growth period to meet requirements of growth ofP. koraiensis trees.

The paper studied and analyzed the threaten land effect of shelterbelt using a quantitative method. A series of effect indices and their calculative methods were put forward. These indices included threaten land height, threaten land angle, useful distance of threaten land or implanting (unsowing) distance, and rate of threaten land, etc.