Studies On Possibility Of Biological Invasion Of Rhus Typhina

In this paper, the methods of the field investigations and laboratory testing were applied to come to a conclusion if Rhus typhina causes the biological invasion for the local environment. The main studies were the effects from Rhus typhina to the native species growth characteristic,the allelopathy of Rhus typhina,the effects on the diversity of understory of Rhus typhina,the effects to the soil physical and chemical properties from Rhus typhina .Finally, in large Rhus typhina tree breeding, will affect the economic, social or unable to meet demand, control measures can be taken.The results show that:(1) The effects from Rhus typhina to Populus tomentosa, Salix matsudana, Prunus tomentosa's growth were inconsistency, but basically it would not inhibit the growth of three species.(2)The roots extracts from Rhus typhina would not affect the own seed germination, but would be affected Amorpha fruticosa and Platycladus orientalis seed germination for different degrees. The allelopathy function from leaf extracts was more obvious than the root extracts'.(3) The vegetation diversity under Rhus typhina for different places, corresponding to the canopy growing and growing characteristics are individual differences. But the growing crown of Rhus typhina and the growth of Rhus typhina were no significant correlation to the characteristics of diversity under the Rhus typhina.(4) Contrast to open space, grass, Prunus tomentosa and Populus tomentosa, the soil moisture content under Rhus typhina was more rich , the gap degree was bigger, bulk density was smaller than other species'. The soil pH under Rhus typhina was approach to other species'.The soil nutrient content under Rhus typhina was more than other species'. So, Rhus typhina could play a huge role in improving soil fertility.(5) A comparison of 10% glyphosate agent and 41% roundup's different concentrations, artificial removed the ground part and uprooting the whole trees was applied. Considering combined control effectiveness and cost control, 41 percent of roundup, concentration 0.3 mL/m~2, the rate of control effect was 99 percent, it is worth promoting and appling in the production.All of the results showed that: Rhus typhina had a certain impact on the local native species growth, but the impact degree was not obviously. Rhus typhina was not dominant species, would not threaten the growth of native trees. So, at present Rhus typhina can not be defined as invasive plants.