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Figure 2.--Changes in protein precipitating ability ("phenolics") of spruce needle extracts during the period of larval
feeding on stand A (identical flushing time). Asterisks indicate significant differences between once-affected (n
= 115)and unaffected (n = 15) trees (levels of significance: * p < 0.05, ** p < 0.0l). Dates of sampling: I) 18
May 1989, 2) 1 June 1989, and 3) 14 June 1989.
500 I
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= -i
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300 ..................................................................................
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i
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1/la total 2/2a basal 2/2a top 3 basal 3 middle 3 top
bud needles needles needles needles needles
Figure 3.---Changes in protein precipitating ability ("phenolics") of"spruce needle extracts of early flushers (i.e., unaffected;
n = 10), and late flushers (i.e., actually affected; n 10) during the period of needle expansion and larval
feeding on stand B. Dates of sampling: early flushers: 1) 3 May 1989, 2) 17 May 1989, and 3) 1 June 1989; late
flushers: la) 1 June 1989, and 2a) 14 June 1989.
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