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tn 8 O- H. radicis<br />

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DISTANCE FROM 1986 MARGIN OF TREE MORTALITY (m)<br />

Figure 2.--Progression of infestation in a declining red pine stand. Infestation rates of the pine root collar weevil, Hylobius<br />

radicis (above) and the pine engraver, lois pini (below) relative to the <strong>or</strong>iginally rec<strong>or</strong>ded margin of killed trees are<br />

shown.<br />

214

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