What's wrong with my plant? : Garden : University of Minnesota Extension

Pine > Trunk/Branches > Fungi growing on trunk or base of tree

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Infected trees have reduced growth, discolored needles, thin canopies; produce large amount of cones and eventually die
Flat white sheets of fungal growth (mycelial fans) between the bark and sapwood at the base of infected trees
Thick, black shoestring-like fungus can sometimes be seen under the bark at the root collar and in the soil near the base of the tree
Base of tree may be encrusted in resin
Wood is decayed, white, soft and spongy, beginning with the roots and may extend from the base of the tree well up into the trunk
Trees frequently break or fall over in storms
Clusters of honey-colored mushrooms may grow at the base of the tree in fall
More information on Armillaria root rot

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Infected trees have reduced growth, discolored needles, thin canopies; produce large amount of cones and eventually die
Heartwood of infected roots and trunks decays, initially turning reddish-brown
As infection continues white pocket rot develops; decayed wood has elongated pockets or pits and may appear honeycomb-like in cross section
Affected trees are often scattered, not adjacent
Infected trees frequently break or lodge during storms
Large mushrooms, velvety brown above and porous, buff-colored below occur at base of tree or above decaying roots some distance away
More information on Tomentosus root rot

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Slow growth, thin canopy and discolored needles in severely infected trees
Infection causes decay of heartwood in trunk and roots
Decaying wood has brown, cubical rot
Affected trees are often scattered, not adjacent
Infected trees frequently break or lodge in storms
10"-12" fungal conk on trunk or several feet away from tree, velvety dark brown above and porous, light brown underneath
Most pines and conifers are susceptible
More information on Brown root and butt rot

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Slow growth, thin canopy, and discolored needles in severely infected trees
Resin soaked bark at base of tree
Sapwood of roots and butt discolored brown
Groups of infected trees commonly found in area where trees have been removed
Wood decays with a stringy white rot
Trees eventually die, windthrow common
Popcorn like white fungal structures that grow into leathery fungal conk, white to reddish brown above, cream colored with multiple pores below
Fungal conks common on cut stumps but often rare on infected trees
Infects most pines and other conifers
Not yet identified in Minnesota; if found, contact Arrest the Pest: 1-888-545-6684 or Arrest.the.Pest@state.mn.us
More information on Heterobasidion root disease and butt rot