矮化香椿园密度、整形和采芽技术研究

在保定郊区建立４种密度的香椿矮化密植园，根据４年的研究，１～４年内以最高密度（３．８株／ｍ２）和高密度（２．５株／ｍ２）的产芽量最高，第４年采完芽后，对最高密度应进行疏伐，保留２．５株／ｍ２；中密度（１．７４株／ｍ２）和低密度（０．８３株／ｍ２）５～１０年内可以不疏伐。结合采芽进行两种方式的整形，即矮干多侧枝型和灌丛型。前者的总产量较高，且可提早１年采芽。采芽３年后，两种整形方式的年产量已无显著差异。采芽与整形相结合，可以促进侧枝和树冠的形成。但是，高密度严重抑制侧枝形成和存活，以至不能形成树冠。矮化密植香椿园第３年的产芽量最高可达５２００ｋｇ／ｈｍ２，年均纯收益为３８９４０元／ｈｍ２。

STUDIES ON PLANTING DENSITY CROWN TRIMMING AND BUD HARVESTING TECHNIQUE OF DWARF CHINESE TOONA ORCHARD

In the suburbs of Baoding city,a closely planted orchard of Chinese toona with four densities wasestablished. Four years of study showed that, in the first four years,the highest bud yields were obtained inthe highest density blocy(3. 8 plants/m2)and the high density blocK(2. 5 plans/m2). After harvesting buds inthe fourth year,the highest density block was thinned to 2. 5 plants/m2. But no thinning was given to themedium density block (1. 74 plants/m2)and the low density block(0. 83 plants/m during the fifth year to thetenth year. Along withbud harvesting, trimming was taken to form 2 different crown shapes. Short trunkwith multi-branches and bush-like. For the multi-branch shape,bud yield was higher, and one year earli-er for bud harvesting. But thre years later,no difference was found in bud yield between the two shapes. Thecombination of trimming with bud harvesting could accelerate the formation of branches and crown. Howev-er,hign density may inhibit branch formation,branch surviving and crown formation. For the closely planteddwarf Chinese toona orchard ,bud yield in the third year can be as high as 5200kg per ha ,and annual incomecan be 38940 yuan per h.