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5`. t F !,e ^d, 6'.'4r '. - s ".. a `aF K " = rM { :. , x . }'2 ak` ' .7�"" af "� t c f i d t 4 i '4 { a s f �c ''° 't P �. , s� t 7y C ^ r�? "-". ,. "° A V yk r Y- VirA`, r 8/20/9 ? >� .. �:• I am offering these general comments%to the neighbors of Hendriekr Park and the City of Eugene Public Works Department in that the ihay be_ helpful in resolving the problem of the "Hazardous Trees "along t)ie Eastern border of the park. The Douglas Fir trees in the area of concern:: South East of the shelter and East of Heights Blvd.. as it progresses in a North /South direction. These trees are a lot older and less vigorous than the Douglas Fir trees south of the Rhododendron Gardens. These trees are located close to. the top of a North /South ridge and on the East face of this ridge up to the East boundary of Hendrick's Park. The soil series, taken from a Lane County soil map is a Steiwer Loam.. this series is found on a 12 to 20 percent slope. The soil depth ranges from 20 to 40 inches arising from a sandstone parent material. The e- ffective rooting depth is also 20to 40 inches. The soil is rather dro- ughty, deoons:ated by the presence of Madrone and other droughty species. The profusion of the existing root systems being partly above the gr- ound indicates the presence of a shallow soil.. Red RingRot formerly known as Fomes Pini is well represented in this stand of trees. The development of the rot is worth noting. The incip- ient and advanced stage of development of this fungus follows the win- ter wood leaving the summer wood generally intact.- The summer_ wood is characterized by a darker color representing the lignin component. The lignin is much stronger- "than;.the cellulose providing moretstructual in- te9rity to the tree. If the summer wood is 0.05 inches or wider the.sp- _ read of the fungus seems •to- z be 'confined`to 'the winterwood ' does" not spread as easily in a' "in - 'the bole of`the'tree. Thus the strucure of the tree pis not ,great y, affectedby this fungus in it's early advanced ::stage.: The, sapwood Gti pe` is rarely ; infected_ with this fungus due to the higher moidturexc�n eit`'of this tissue. Red Brown Butt Rot or Polyporus_Schweinitzii is a cubical brown rot generally affecting the lower eight feet of the first log of the tree. More often the first two to four feet of the tree is all that is.en- volved.. The fruitng body is a flat shelf,like velvety structure. None were observed in this area. Sometimes abtokma1 swelling of the bole is an indicator of this fungus infection. However in this case due to the proximity to the ridge line any swelling with no fruiting body observed would seem to be the result of normal buttressing of the tree bole in response increased wind velocity. Again the heartwood is more suscept- able to invasion by this fungus than the sapwood due to the higher moisture content of the latter. Tree 'failure occurs due to this fungus only with the development of the advanced stageand then only when that stage affects the root tissue. Yellow Ring Rot /Laminated Root Rot formerly . known as Poria Weirii.yis endemic to this area. This fungus's advanced stage weakens . the`;sup - porting root structure causing the tree to. fall.. Assessment of the_ pre- sence of the incipient stage of this fungus can only be determined „by a hand lens examination of the root crown and the bark on the 'roots. ' The fruiting body is seldom seen. My physical examination of the trees in this area on the 18th and 19th of August 1997 showed the existance of Red Ring Rot, that being demon - strated'by the presence of that rot's fruiting body. The stage of fungus infection- incipient or advanced is unknown A educated guess could be made by boring the infected tree with an increment borer, extracting the core, and examining the core with a hand lens to. determine the pre-