Root Diseases
Schweinitzii Root & Butt Rot Phaeolus schweinitzii (Fr.) Pat. Hosts-- Douglas-fir is by far the most common host. All conifers are susceptible, especially to butt rot.
Distribution-- Range of hosts in Idaho and Montana.
Damage-- Decays inner wood of roots, causes root galling, and decays butt heartwood. Windthrow frequently results from uprooting or butt breakage. Douglas-fir beetles and Armillaria ostoyae often attack P. schweinitzii-infected Douglas-firs.
Identification-- Trees infected with P. schweinitzii alone seldom have distinct root disease crown symptoms. Those that do are usually found on poor soils or rocky and dry sites. Crowns of extensively infected Douglas-firs are sometimes thin and show poor shoot growth and some branch dieback. Decay is dry and yellow at first, becoming brown and cubically cracked in advanced stages (figs. 129, 131). Thin, resinous felts are often present in cracks of advanced decay. Conks are occasionally produced on the ground near infected trees stumps. Less often, they develop directly on infected trees or stumps. They are annual, spongy conks with large pores on the undersurface. Caps are brown and velvety (figs. 130, 132); undersides are green when fresh becoming brown with age. Caps are usually 5-10 inches in diameter with short stems. Large clusters often form. Figure 129. Brown cubical decay in the butt end Small roots that are infected of the first log is the most common indication have dark red-brown, resinous centers of schweinitzii root and butt rot. (fig. 133). Roots may be stubbed with gall-like swelling. These stubbed roots have red-brown resinous heartwood which may also show brown cubical decay (fig. 134).
Similar damages-- The decay caused by Fomitopsis pinicola is also brown and cubically cracked. However, F. pinicola decays dead trees and decays both sapwood and heartwood. Mycelium felts in F. pinicola decay are thick and not resinous, and F. pinicola conks are frequently found in association with the decay. Figure 130. An old conk resembles a bovine manure pile in size and color. References-- See full guide. 84 Root Diseases
Figure 131. Schweinitzii root and butt rot is the most common brown cubical decay of Douglas-fir. It is common in other conifer species as well. The disease often starts in the roots when trees are young but is seldom seen causing butt rot until trees are mature or overmature. The cull usually only extends eight feet or less above the ground. Fruiting bodies are present on both of these examples but they are not commonly produced in this way. Usually they are found on the ground within a few feet of an infected tree. A single conk may indicate extensive infection throughout a stand.
Figure 132. Phaeolus schweinitzii conks are yellow-green when fresh but age rapidly to a yellow-brown and finally dark brown color. They have a velvety cap, a short stem (stipe), and a pored green to brown lower surface.
Figure 133. Small diameter roots sometimes have a dark red resinous heart when infected by P. schweinitzii.
Figure 134. Roots of windthrown trees with schweinitzii root and butt rot commonly are stubbed and have gall-like swelling. 85 Root Diseases
Table 3. Comparing Important Root Diseases.
OTHER BASAL FUNGUS HOSTS DECAY DISTINGUISHING RESINOSUS CHARACTERISTICS
,FW,FG,FD SE,FAS,FR roetihW depahs-nafkcihT Armillaria gnilpas ,hsiwolley etihwfostlef seY ostoyae senip htiwygnirts mycelium under senilenozkcalb bark srefinocllA
deroloc-maerC ,detanimaL retuonomuilecym FG,FD tagnitarapes stoorfokrab Phellinus ,sgnirlaunna ;ffudrednu seY sulphurascens rehtO htiwdettip wolley-nomannic srefinoc dezis-daehnip krabnimuilecym seloh maerchtiwskcarc muilecym
rognivlehssknoC ,FG,FD nidesserppa ,FW,FAS rospmutswolloh Heterobasidion FR occidentale roetihW stoorno rehtO ,hsiwolley ;dnuorgrednu srefinoc otygnirts ecafrusreppu oN tahwemos rewol,nworb ;etanimal rolocmaercderop etihwralugerri -nonnworbhtiw Heterobasidion PP htiwstkcop ;nigramderop skcelfkcalb deroloc-maerc irregulare Other pines rarely nottub(sdnuom gnildeesno)sknoc stoor
htiwstoorllamS nworb-der center;suoniser egral;stoordellag FD lacibucnworB ytevlev,nworb Phaeolus oN dnatoorfotor neerghtiwsknoc schweinitzii rehtO doowtraehttub eropnworbro srefinoc e;disrednunoreyal p nodecudor eertrodnuorg esab
kradrokcalB Leptographium PP,PNP edoN c ya niniatsnworb oN wageneri decudorp swollofdoowpas FD,PL sgnirlaunna
ronworb-deR niniatsnworb 5-2sknoc;toor PPL,SB,SE tekcopetihW Onnia otwolley,sehcni ,egralhtiwtor tomentosa oN reppunomannic rehtO s depahs-eldnip trohshtiw;ecafrus srefinoc stekcopytpme natotmaerc;epits rewoldiorop ecafrus
BS=Colorado blue spruce, DF=Douglas-fir, ES=Engelmann spruce, GF=grand fir, LPP=lodgepole pine, PP=ponderosa pine, PNP=pinyon pines, RF=red fir, SAF=subalpine fir, WF=white fir. 77 Stem Decay
Table 1. Comparison of Common Heartwood Rots.
FUNGUS HOSTS CONKS
Shape Upper Lowe r and surface surface Context Location
Echinodontium GF, WH, Tan; teeth tinctorium Hoof, under Brown, Orange SAF branch woody projecting Indian paint downward
DF, LPP, Phe llinus pini WL Hoof or flat Dark Cinnamon to Cinnamo n Pini or Other on bark brown tan red ring rot conifers
Onnia ES, LPP Mushroom- Gold to tomentosa like with brown, Tan to gold, Gold, leathery cap velvety; brown with brown with Other and central age; pores. age Tomentosus conifers 1-4 inch root disease stalk. On diameter ground
Phaeolus DF Non-woody; Green when schweinitzii Brown, fresh, brown Brown thick shelf or velvety Other on ground with age; Root & butt rot conifers large pores
Fomitopsis WL, PP Hoof or Ye llow, Yellow- officinalis cylindric, Ye llow or white; white, or white; pored Other large cream chalky Brown heartrot conifers consistency
Fomitopsis Ve ry Brown, Cream; pinicola All dead common; gray, red Cream; conifers corky thick shelf or band at small pores consistency Red belt fungus hoof margin
Heterobasidion GF, ES, Thin hoof or Cream; spp. WH, WPP, flat on bark, small pores; Leathery Gray or when fresh, SAF, DF inside hollow brown margin Annosus root stumps or on brown with woody disease PP roots age with age
Phellinus Conks very GF, DF, Tan; brown sulphurascens rare; thin, flat with age; WH on bark; light none Brown or SAF fuzzy setal yellow-tan Laminated weight, brittle hyphae root rot with age
Phellinus Conks are uncommon. Phellinus weirii (p. 26) and we irii P. sulphurascens (p. 82-83) are differentiated WR C mostly on the basis of host, although there are Cedar laminated butt microscopic differences in conks and cultural rot characteristics.
Postia Conks rare; White or sericeomollis ve ry thin, flat White or cream; WR C on bark or none cream, small very thin; Cedar brown decayed pores brittle with pocket rot wood; bitter age
Host key for Table 1 (p. 34): DF=Douglas-fir, ES=Engelmann spruce, GF=grand fir, 34 LPP=lodgepole pine, PP=ponderosa pine, SAF=subalpine fir, WH=western hemlock, WL=western larch, WWP=western white pine, WRC=western redcedar Stem Decay
Table 2. Decays of Common Heartwood Rots.
FUNGUS DECAY NOTES
Echinodontium Ye llow to orange, stringy; Conks common tinctorium confined to heartwood
Red-brown discoloration in heartwood; pronounced white, Phellinus pini spindle-shaped pockets with Punk knots and conks firm brown wood between; common becoming stringy, white decay in most advanced stages
Root disease; fruiting Pronounced white or hollow Onnia tomentosa bodies leathery, pockets, honeycomb mushroom-like, and rare appearance in cross section in this region
Brown cubical decay of stem Root disease; conks and root heartwood; thin, common on ground, Phaeolus schweinitzii resinous felts may be present occasional on butt; dark in shrinkage cracks of decay red-brown heart in small roots
Brown cubical decay of stem Conks rare; infections Fomitopsis officinalis heartwood only; thick, white, generally high in tree; mycelium felts in shrinkage not originating from cracks roots
Brown cubical decay of both Dead trees and stumps; sapwood and heartwood; decay not restricted to Fomitopsis pinicola forms crumbly decay with heartwood; conks firm cubes common
Root disease; butt Heterobasidion White rot; somewhat heartrot common in old laminating, stringy, with grand fir, hemlock, occidentale and irregular white pockets and H. irregulare spruce, cedar, and small black flecks ponderosa pine
Decay is distinctly laminating Root disease; butt Phellinus weirii along the annual rings; tiny heartrot common in live and white pockets or hollow pits grand fir, hemlock, P. sulphurascens throughout; often filled with white pine, and cedar cinammon-brown setal hyphae (comments in Table 1)
Brown cubical decay in large Heartrot very common Postia sericeomollis pockets (several inches to in western redcedar several feet in length)
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