The standards of forest regeneration survey of Prof. V. G. Nescherov. USSR and many authors of other country are compared and studied. Some of them take the ideal of deriving regeneration standards from yield tables as the basis of their studies. It is necessary to take the number of trees per hectare of different age classes in yield tables as a reference of projecting the standards,of forest regeneration survey for various types and site classes of different tree species. Plot the number of trees over the average diameter on the double logarithmic paper it is found that the curve appearing negative and slightly convex upward which superposes the mortality of fully stocked stands. As the horizontal line on above graph denotes no decreasing of number of trees with increasing average diameter, the most probable case of mortality after forest regeneration will follow the equal divided line of the angle made by the horizontal line and that curve. Take 5 cm, 10 cm, 15 cm and 20 cm as the predicting average diameters of fully stocked stands, four parallels can be drawn from corresponding points on that curve with the same slope as the divided line of that angle. These four parallels cut the area under curve into 5 parts which might represent 5 grades of forest regeneration. Therefore the predicting average age, average diameter and average number of trees per hectare for the regenerated stands for each grade can be figured out. According to above method, the author develops 216 allometric equations and corresponding standards of forest regeneration survey for 54 site classes or types of main tree species in China that have yield tables already constructed. The author adopts the degree of stocking as a proper index of seedling distribution. The percent of plot which incur seedling on a series of plots by systematic sampling will denote the degree of stocking. It is proposed that the small plot should be circular in. shape and its area should be approximately equal to the average crown projection area of the premature trees of various species. As the stands grow old, the crown canopies begin to close up, the degree of stocking becomes greater and greater till 100% or more. The calculating measure of degree of stocking of regenerated stands must be concord with that old stands though they are based upon different mensurational elements so that the stands can be managed and thinned in a unified way. The principle and method of calculating the degree of stocking for multiple species and for stands with different mensurational basis are also mentioned. Finally, proposals and betterments are given to the method of survey for various ways of forest regeneration.

Methods of soil and vegetation survey generally used for forest trees in mountainous areas are considered inapplicable to poplars growing as scattered trees on the levelland. In the present paper, therefore, a method catering for this purpose together with the result of its application to poplar sheltabelts in East Honan is presented. In soil survey, besides detailed profile descriptions, field determinations of important soil properties, including water permeability, volume weight, moisture content, texture, ground water table and composition, thickness and depth of clay layer, pH value, available N and available P have been obtained. All the data are later annalysed and interpreted from two rather different but complementary approaches. On the first hand, by the calculation of correlation coefficient, correlation between height growth of Populus pyramidalis and ground water tables is found to be significant (r=0.458 P<0.05), and correlation between height growth of this species and volume weight of soil at root-concentrating horizon highly significant (r=0.804 P<0.01). But correlation coefficient between height growth of the same species and all other studied soil properties fall below the significant leyel generally adapted i.e. 5% level. Secondly, on the comparative study of field determinations of soil properties and height measurements of this species, ground water tables with reference to tree heights are divided into 3 classes, soil textures 4 classes, pH values (at root-concentrating horizon) 3 classes, and volume weights 3 classes respectively. In vegetation survey, qualitative investigations are carried out following the ZurichMontpellier School's procedures with but a few modifications, and total estimation, sociability, aspect, life form, root system and plant height are recorded. Also, point quadrat method is employed to collect quantitative data such as cover and frequency. Populetum pyramidalise association is classified into two subassociation:P. Pyr. Imperata cylindrica subassociation and P. Pyr. Imperata cylindrica var. major subassociation respectively. The latter is further classified into Lactuca variant and typical variant. To the above-mentioned plant community units and their respective differential species, a weighted mean of the class value with respect to each soil property is calculated separately. On this basis their indicating values to the growth of the tree are interpreted. Meanwhile, quantitative criteria of soil properties and a list of plant indicators (including individual species and community units) for the choice of planting sites of Populus pyramidalis in the studied area are given. Lastly, merits and demerits of the present method are discussed.

During the period of August-November, 1960, observations were made to investigate the characteristics of radiation balance, heat balance, and microclimate in the forest of Hainan, Kwangtung. The results of the observations may be summarized as follows: 1) In the forest the radiation intensity and the heat exchange are much weaker than on the open ground. 2) The radiation heat is mainly spent on the soil heating and evaporation in the forest, but mainly on the air heating and evaporation on the open ground. 3) In the forest the soil and air temperatures are lower, but the humidity is higher than on the open ground. Therefore, the microclimate in the forest is cool and moist, while that on the open ground is hot and dry.