Figure 1— Location oi Armillaria survey plots installed in 1983. 



Table 3 — Incidence of Armillaria spp. rhizomorphs on healthy and 

 dead conifers or healthy hardwoods growing on random- 

 ly located 0.04-ha plots within habitat types supporting 

 Armillaria spp. in Northern Rocky Mountain National 

 Forests 





Number 



Number 



Proportion 





plants 



with 



with 



Materials 



Inspected 



rhizomorphs 



rhizomorphs 



Healthy hardwoods 



203 



162 



0.80 



Dead conifers 



110 



95 



.86 



Healthy conifers 



380 



164 



.43 



= 107.48, d.f. = 2, prob. of larger = 0.0005. 



Table 4 — Incidence of culturally verified Armillaria spp. rhizo- 



morphs on healthy conifers growing within habitat types 



supporting Armillaria spp. 









Number 



Number 



Proportion 





plants 



with 



with 



Conifer species 



inspected 



rhizomorphs 



rhizomorphs 



Ponderosa pine 



18 



6 



0.33 



Lodgepole pine 



39 



12 



.31 



White pine 



19 



6 



.32 



Douglas-fir 



72 



39 



.54 



Western larch 



51 



22 



.43 



Western hemlock 



14 



8 



.36 



Western redcedar 



25 



5 



.20 



Engelmann spruce 



50 



16 



.32 



Grand fir 



61 , 



39 



.64 



Subalpine fir 



31 



11 



.35 



X2 = 26.33, d.f. = 9 



, prob. of larger 



= 0.005. 





4 



