Effects of waterlogging on the growth and energy-metabolic enzyme activities of different tree species. Effects of Water Extraction from Roots of Carya illinoensis on Seed Germination and Seedling Growth of Two Crops Study on Nut Characteristics Variation and Superior Tree Selection of Carya illinoensis A Compara tive Study on Nut Character istics of Pecan Observation and Comparison of Flowering Phenology of Different Carya illinoensis Clones Comparison of Leaf Photosynthetic Physiological Characteristics in Vive Carya illinoensis Varieties Allelopathic Effects of Water Extractions from Leaves and Husks of Carya illinoensis on Three Plant Species