Growth conditions,symptoms of ancient trees in the Master-of-Nets Garden were investigated,it was found that there were 6 ancient trees about 120-920 years old in this garden,belonging to 5 genera and 5 families.Generally speaking,ancient trees in this garden grow well due to the proper protection,and 3 of them need only regular management,specifically,Pinus bungeana Zucc.,Podocarpus macrophyllus(Thunb.)D.Don,Wisteria sinensis Sweet in south yard of Dianchun Yi(the Peony Study),while another three need key protection,specifically,Chaenomeles sinensis Koehne,Sabina chinensis(Linn.)Ant.,W.sinensis Sweet,2 of which need corrosion prevention and filling protection,and another one needs comprehensive techniques for the rejuvenation of tree vigor.In view of symptoms of these 3 trees requiring key protection,corresponding techniques were proposed as below:3 steps for protecting C.sinensis Koehne(A.clearing and sterilizing tree holes,painting anti-corrosion protective agent;B.filling holes;C.sealing holes);3 steps for protecting W.sinensis Sweet(A.clearing up rotten xylem;B.anti-corrosion and sterilization processing for trunk;C.painting anti-corrosion agent);4 steps for S.chinensis(Linn.)Ant.(A.clearing climbing plants around it;B.clearing rotten xylem;C.filling holes;D.improving rhizosphere and rejuvenation of the tree).
