Forest Health Protection Pacific Southwest Region

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1 Frest Health Prtectin Pacific Suthwest Regin Date: June 7, 2013 File Cde: 3420 T: Subject: Patricia Grantham, Frest Supervisr, Klamath Natinal Frest Bilgical Evaluatin f the Jess Prject Area, Salmn River Ranger District, Klamath Natinal Frest (FHP Reprt N. N13-02) At the request f Marissa Jnes, Pete Angwin (Plant Pathlgist) visited the Jess Prject Area n the Salmn River Ranger District n May 9, Pete was jined by Marissa Jnes (Frestry Technician), Rger Siemers (Silviculturist) f the Klamath Natinal Frest, and Bill Jnes (Cntract Silviculturist). The prject area is near the Nrth Frk f the Salmn River and the twn f Sawyers Bar. Tw Prject Area Units, 122 and 101, were visited. Bill Jnes said that these Units were als representative f ther Units in the Jess Prject Area. The purpse f the visit was t assess insect and disease cnditins and prvide recmmendatins fr the enhancement f frest health and stand resilience. Backgrund While the Jess Prject Area is nt in a Late Successinal Reserve (LSR), it is in an area that is prpsed fr critical nrthern sptted wl habitat. The purpse f the prject is t imprve the cmpsitin, structure and functin f the frest ecsystem, prvide resilience t fire and insect and disease attacks, reduce fire risk t nearby cmmunities, and prmte the ecnmic stability f lcal cmmunities. Ideally, the pst-restratin frest wuld have a mixture f seral stages, prviding a sustainable habitat fr a diversity f terrestrial and aquatic species. Observatins Unit 122 Unit 122 is apprximately 80 acres in size, lcated at N , W Vegetatin in the mixed cnifer verstry and understry is dminated by Duglas-fir and lesser amunts f white fir, with scattered pndersa pine, sugar pine and incense cedar (Figure 1). Cunting the tree rings f the stump f a recently cut Duglas-fir indicated that the verstry is apprximately 180-years ld. A marked reductin in the size f the utermst 21 tree rings indicated recent grwth reductin, mst likely due t impacts f drught, disease and/r inter-tree cmpetitin (Figure 2). Duglas-fir dwarf mistlete (Arceuthbium duglasii), as indicated by brms in the branches, is widespread and cmmn in the Unit. The infectin level is high, with trees with a brm vlume ratings (BVR) f 4-6 were cmmn. Brm vlume rating is a 1

2 mdificatin f the Hawkswrth 6-class dwarf mistlete rating system, develped by Tinnin (1998). Under Tinnin s rating system, BVR classes range frm 0 fr nn-infected Figure 1. Vegetatin at Jess Prject Figure 2. Duglas-fir stump at Jess Prject Area, Unit 122. Area, Unit 122. trees, t 6 fr trees with at least 50% f the crwn vlume ccupied by dwarf mistlete brms in each third f the live crwn. White fir dwarf mistlete (Arceuthbium abietinum, f. sp.cnclris) was als widespread in the white fir in the Unit. Althugh heavily infected white fir was nt uncmmn, with Hawkswrth Dwarf Mistlete ratings (DMRs) f 4-6, it did nt appear t be quite as extreme as the dwarf mistlete in the Duglas-fir. Hwever, the dwarf mistletes are undubtedly cntributing greatly t tree stress and mrtality in the Unit, particularly during perids f drught. An apprximately 2-acre pcket f dead and dying Duglas-fir was nted in the Unit. Affected trees were heavily infected with Duglas-fir dwarf mistlete. Clse examinatin revealed n signs f black stain rt disease r any ther rt disease, thugh galleries f a wd-bring beetle (mst likely the flatheaded fir brer, Melanphila drummndi) were fund. Sme trees were streaming pitch high up in the ble, pssibly due t the wd brer. The flatheaded fir brer typically attacks trees that are under stress, prviding further indicatin that the trees had been greatly weakened by drught and dwarf mistlete. Unit 101 Unit 101 is lcated at N , W , and is a mixed cnifer stand that cnsists f Duglas-fir, white fir, pndersa pine and sugar pine in the verstry, with mstly Duglas-fir and white fir, and lesser amunts f pndersa pine, sugar pine and incense cedar in the understry (Figure 3). Stcking in the Unit is very high. As in Unit 122, infectin levels f dwarf mistlete in bth Duglas-fir and white fir are high, with many f the infected trees having DMRs r BVRs f 4-6. In additin, sme f the incense cedar were infected with incense cedar true mistlete, Phrdendrn juniperinum spp. libcedri. 2

3 Figure 3. Vegetatin at Jess Prject Area, Unit 101. Recmmendatins and Cnclusins It is bvius that the trees in the tw units in the Jess Prject Area are under a great deal f stress, due t the cmbined effects f high stcking and drught. The Duglas-fir and white fir in these Units are under added stress due t the impacts f the widespread and severe levels f their respective dwarf mistletes, which is causing mrtality in all sizes f these trees. While dwarf mistlete is a natural cmpnent f many frest stands, and prvides imprtant nesting habitat fr a wide variety f bird species (including the nrthern sptted wl), this level f the pathgen, which has been able t increase due t the effects f many years f fire suppressin, is nt. In additin, dwarf mistlete seed is cntinually raining dwn nt the understry, perpetuating and accentuating the prblem. Als, fire risk is high due t the mrtality and brms, creating fuels in all levels f the Units. Cntinued mrtality may be expected in the mst highly infected Duglasfir. Mallams (2007) evaluated a series f permanent mnitring plts that were set up t mnitr spread and impact f Duglas-fir dwarf mistlete in similar mixed cnifer stands in suthwest Oregn and fund that 45% f class 6 DMR/BVR-rated DF died in the 10- year mnitring perid, and 11% f class 5 DF died. In additin t the direct effects f drught and dwarf mistlete, the enhanced fuel levels culd lead t the lss f the area by wildfire. This situatin is nt sustainable. Withut active management, the Units will nt be able t maintain ld grwth characteristics r wildlife habitat (including nesting habitat in the brms f Duglas-fir), while the cntinued infectin f yunger understry Duglas-fir will limit the ability fr them t grw int large ld trees that will survive fr many decades. My recmmendatins fr these Units, and fr ther similar Units in the Jess Prject Area, are as fllws: 3

4 Thin t a wider spacing t increase species diversity and drught tlerance f the remaining trees. Favr nn-dwarf mistlete hst species including pndersa pine, sugar pine and incense cedar, then Duglas-fir and white fir Reduce dwarf mistlete levels in the thin. Discriminate against Duglas-fir and white fir with DMR/BVRs greater than 2.0 and thse with infectins high in the crwn. Smaller heavily infected understry DF and WF are very unlikely t reach large enugh size t prvide desired ld grwth and wildlife characteristics (Mallams, Gheen and Russell 2005; Mallams 2007), s discriminate against them as well. This treatment will invlve the remval f many heavily-infected large verstry Duglas-fir and white fir t reduce the amunt f dwarf mistlete seed raining dwn nt the develping understry. Because the impacts f true mistlete n its hsts are much less than thse f dwarf mistletes, and is spread by birds rather than by aerially-dispersed seeds t adjacent and vertpped trees, it is nt necessary t discriminate against incense cedars that are infected with incense cedar true mistlete. In areas where it is desirable t retain r maintain Duglas-fir dwarf mistlete brms fr enhanced sptted wl nesting habitat, fllw the recmmendatins f Marshall, Mamne and Barclay (2003), Mallams, Gheen and Russell (2005) and Mallams (2007) as fllws: Clump infected Duglas-fir tgether, surrunding the grup with ther nn-hst species (pine and incense cedar) t minimize lateral dwarf mistlete spread. Manage fr several clumps f infected Duglas-fir cvering ne-third t ne-half f a 20-acre nest stand. Manage current nest habitat t include ne heavily-infected clump having at least ne Type 2 r Type 3 brm and several lightly infected clumps. These will likely nt survive well ver the lng haul (will die due t stress r fire), s manage fr replacement nest trees as described in the next bullet statements. Nte: Type 2 brms are thse that riginate and are within a few feet f the ble and Type 3 brms riginate and are attached t the ble (Tinnin and Knutsn 1985). These are the best kinds fr nesting and cver. Select infected clumps fr replacement habitat that have infectins in the lwer third f the tree crwn and Type 2 r 3 brms wherever pssible. Manage these clumps t keep infectins in lwer third as lng as pssible. This will create the least negative impact n tree vigr. Thinning arund these trees can als help prmte tree vigr and brm grwth. Favr infected areas that are n the lwer t middle third f the slpe t minimize the rate f DM spread frm tree-t-tree thrugh the stand. Overall, the bjectives f the treatments are t increase tree vigr and significantly reduce the incidence and impacts f dwarf mistlete, while retaining sufficient numbers f nesting trees (with Type 2 and 3 Duglas-fir dwarf mistlete brms) fr wildlife habitat in specific areas, and prviding fr the recruitment f new nest trees t replace nes that die. Pst-treatment mnitring will be extremely imprtant t track any 4

5 additinal pst-treatment mrtality, increases r decreases in fuel levels, the release f retained trees, the status f existing nest trees and the recruitment f new nest trees, and t ensure that dwarf mistlete grwth is nt faster than tree grwth. This will nt be a treatment that can simply be dne and then ignred. If yu have any questins regarding this reprt r need additinal infrmatin, please cntact me at /s/ Pete Angwin Pete Angwin Plant Pathlgist Nrthern CA Shared Service Area CC: Marissa Jnes, Bill Jnes, Rger Siemers, Carl Varak, Sam Cuenca, Anne Mileck, Dave Hays, Phil Cannn References Mallams, K.M Permanent plts fr measuring spread and impact f Duglas-fir dwarf mistlete in the suthern Oregn Cascades, Pacific Nrthwest Regin: results f the ten year remeasurement. USDA Frest Service Pacific Nrthwest Regin, Suthwest Frest Insect and Disease Service Center, Central Pint, OR. SWOFIDSC p. Mallams, K.M., D.J. Gheen and D. Russell Dwarf mistlete brm develpment in mature Duglas-fir trees: a retrspective case study. Nrthwest Science 79(4): Marshall, K.M., M.M. Mamne and R.Barclay. A survey f Duglas-fir dwarf mistlete brms used fr nests by nrthern sptted wls in the Applegate Ranger District and Ashland Resurce Area in suthwest Oregn. Western Jurnal f Applied Frestry 18(2): Tinnin, R.O An alternative t the six-class dwarf mistlete rating system. Western Jurnal f Applied Frestry 13(2): Tinnen, R.O. and D.M. Knutsn Hw t identify brms in Duglas-fir caused by dwarf mistlete. USDA Frest Service Research Nte PNW-426. Pacific Nrthwest Frest and Range Experiment Statin, Prtland, OR. 8p. 5