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Pine > Needles > Slow growth, discolored needles, thin canopy throughout the entire tree

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Adults bore numerous holes less than 1/8 inch diameter in bark which can resemble being shot by a BB gun or shot gun
Entrance holes often have a reddish-brown, resin-soaked fine sawdust
Larvae feed under bark
Needles turn yellow and reddish-brown
Adults are dark brown to black and range in size from about 1/8 to ¼ of an inch long
Favors stressed pines of all species
More information on Ips bark beetles

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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
Base of tree may be encrusted in resin
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
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 growing 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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Large amounts of pitch are exuded, darkening the root collar and nearby soil
Discolored needles, from yellow to reddish-brown on entire tree
Infested trees often tip due to feeding damage
Most pine attacked; prefers pine growing on sandy soils with heavy grass competition
Adults are ¼ inch long, reddish brown to black with whitish to yellowish spots (patches of scale); has conspicuous snout
Larvae about ⅓ inch long, whitish and grub-like
More information on Pine root collar weevil

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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