Termite attacks on living trees, as have been reported, were globally reviewed from the viewpoints of regional details, ecology and practical control. To properly understand the phenomena of termite-tree interactions, it is necessary to understand both termites and trees adopt evolutionary stable strategies. Reviewing the phenomena with the viewpoints of termites' behavioral ecology and tree physiology leads to a hypothesis that almost all the termite damages on living trees all over the world can be elucidated as either (1) a consequence of symbiosis between termites and trees with little fitness loss of trees, or (2) a result of termites' optimistic attacks due to trees' weakening through the other causes. In controlling termites damaging constructions and surrounding trees simultaneously, trials based upon the theory of integrated pest management (IPM) are needed, utilizing bait formulations in most of the cases. Also in Japan, an administrative improvement is needed to facilitate the problems of separated registration systems of indoor and outdoor pesticide usage.

The effects of auxin and cytokinin phytohormones combined with girdling on the sprouting ability of Robinia pseudoacacia before and after bud breaking were examined. Experiments were carried out in a greenhouse of the Arid Land Research Center, Tottori University. The six treatments were a combination of girdling as auxin transport inhibition, exogenous auxin (NAA), cytokinin (BAP), or only lanolin (Control) as an application solvent. Sprouting was observed for seedlings with girdling before and after bud breaking. Girdling treatment increased the number of sprouts per seedling, but girdling treatment combined with NAA had negative effects on sprout development. These results suggest that sprouting of R. pseudoacacia was promoted by girdling, and that the promotive effect was lower before bud breaking. However, there was no significant difference in the growth of sprouting that occurred before and after bud breaking.

Brown root rot caused by Phellinus noxius is a serious plant disease, and has been causing serious problem in tropical and subtropical regions. At present, the only effective control procedure is entirely removing infected trees and the surrounding soil. However, these measures are labor-intensive and time-consuming, therefore practical alternatives is necessary. We evaluated the effects of two fumigants chloropicrin and dazomet on P. noxius. Branches artificially inoculated with P. noxius were buried in soil and subsequently fumigated. After fumigation, the branches were collected and examined for the presence of P. noxius. No P. noxius was isolated from branches retrieved from chloropicrin-treated soil, whereas the isolation rate of P. noxius from dazomet-treated was significantly lower than the control. In addition, to confirm the workability and safe practical use of chloropicrin, we established a test plot (6.5 m×12 m). The treatment took 7 hours by 5 workers. During the test period, no gas leakage was detected outside the covering sheet. In addition, any gas was not detected inside the sheet, 11 days after fumigation treatment. We accordingly confirmed that chemical fumigation with chloropicrin and gas barrier film could be safely applied for control of P. noxius even at practical scale.