Timing of Tree Attack. The seasonal incidence of
tree attack by ambrosia beetles was determined by
examining chestnut trees, Castanea mollissima Blume,
for new entry holes (galleries). Five trees (1.0- to
1.9-cmcaliper at 15.2 cmhigh) were transplanted at
four locations on the Nursery Station on 8 February
1999. Each plot was2 mfromthe edge of a deciduous
forest, and trees were planted at a 3-mspacing. Plots
were maintained with mowing, and trees were irrigated
as needed. On 9 February, a 35-ml volume of
Osmocote 8 mo slow release fertilizer (18Ð6Ð12; NP-
K) was broadcast around the base of each tree.
Trees were examined approximately three times per
week fromFebruary to late July by thoroughly examining
the trunk and branches for new ambrosia beetle
galleries. After July, trees were examined weekly until
15 May 2000. For each new gallery, information recorded
included the date of Þrst observance, the
height fromthe soil surface, the caliper of the limb at
the bore location, and the compass direction of the
bore entrance. The height, cardinal direction, and
caliper of the stemat the entrance site of each gallery
was compared between major species of ambrosia
beetles using analysis of variance (ANOVA) for a
randomized complete block design on log10 (X
0.0001) transformed data, and means separated by
least signiÞcant difference (LSD) Test ( 0.05)
(SAS Institute 1997). Other characteristics recorded
for some galleries included unusual location (e.g., bud,
leaf scar) or excrement nature (e.g., toothpick
strands). The number of new tree attacks was contrasted
with the number of trap captures for the dominant
species.
Timing of Tree Attack. The seasonal incidence oftree attack by ambrosia beetles was determined byexamining chestnut trees, Castanea mollissima Blume,for new entry holes (galleries). Five trees (1.0- to1.9-cmcaliper at 15.2 cmhigh) were transplanted atfour locations on the Nursery Station on 8 February1999. Each plot was2 mfromthe edge of a deciduousforest, and trees were planted at a 3-mspacing. Plotswere maintained with mowing, and trees were irrigatedas needed. On 9 February, a 35-ml volume ofOsmocote 8 mo slow release fertilizer (18Ð6Ð12; NP-K) was broadcast around the base of each tree.Trees were examined approximately three times perweek fromFebruary to late July by thoroughly examiningthe trunk and branches for new ambrosia beetlegalleries. After July, trees were examined weekly until15 May 2000. For each new gallery, information recordedincluded the date of Þrst observance, theheight fromthe soil surface, the caliper of the limb atthe bore location, and the compass direction of thebore entrance. The height, cardinal direction, andcaliper of the stemat the entrance site of each gallerywas compared between major species of ambrosiabeetles using analysis of variance (ANOVA) for arandomized complete block design on log10 (X 0.0001) transformed data, and means separated byleast signiÞcant difference (LSD) Test ( 0.05)(SAS Institute 1997). Other characteristics recordedfor some galleries included unusual location (e.g., bud,leaf scar) or excrement nature (e.g., toothpickstrands). The number of new tree attacks was contrastedwith the number of trap captures for the dominantspecies.
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