) ENVIRONMENT -q=1rotection

Transcription

1 ) ENVIRONMENT -q=1rotection USDA FOREST SERVICE NORTHERN REGION Stte & Pvte Forestry Missoul, MT 5981 ccol' 931; JUN Sim,. p " r+- N opsn'y 1 1>N6-.k ill 91. g, v 52 Apl 1976 EVALUATION OF MOUNTAIN PINE BEETLE INFESTATIONS, GALLATIN RANGER DISTRICT, GALLATIN NATIONAL FOREST MONTANA, 1975 By M.D. McGregor, D.R. Hmel, nd R.C. Lood ABSTRACT Mountin pine beetle hs occurred t epidemic level in lodgepole pine stnds in the west Glltin River dnge since Infesttion now encompsses bout 5,5 cres. Since 1969, pproximtely 463,212 trees, with n estimted volume of 2,529,244 bord feet hve been killed. Approximtely 69 percent of the stnds on the Glltin Distct re clssed s susceptible. It is predicted tht bout 927,781 trees will be killed in Selective logging to remove infested nd susceptible trees is recommended to reduce the potentil for continued epidemic. INTRODUCTION Mountin pine beetle, Dendroctonus ponderose Hopk., developed to epidemic sttus in lodgepole pine stnds, Pinus contort vr. ltifoli Engelm., in the west Glltin River dnge in Number of newly ttcked trees incresed stedily through 1972, nd surveys showed pproximtely 22,354 trees contining 1,61,722 bord feet (212,344 cu.ft.) were killed through Direct control in 197 nd 1972, consisting of felling nd burning nd slvge logging brood trees, hd little effect in lteng the course of the outbrek. Since suppression ws only done on limited bsis, nd the mjoty of infested trees were left untreted, buildup rtio of old to newly ttcked trees exceeded 1:1 yerly.

2 A significnt increse in crege infested nd number of newly ttcked trees ws detected dung the nnul insect nd disese el detection flight in 1975 (Figure 1). Becuse of the mrked expnsion in outbrek re, the Glltin Rnger Distct initited opertionl surveys to determine number of newly ttcked trees nd volume loss per yer, nd to delinete res of most severe infesttion. By delineting these res, slvge logging or selective cutting of the more susceptible trees might be implemented to reduce the epidemic potentil in mny res. METHODS Groudd surveys were conducted on 5,457 cres (2,28 h) dung November Vble plots (BA=1) were locted t 5-chin intervls on lines 5 chins prt. Spiegl Relskops were used to tlly trees in ech plot. All trees 5 inches (13 cm) d.b.h. nd lrger were tllied in ech plot. Dt ws recorded ccording to FSM 52 R-1 Supplement No. 8, July Survey dt were nlyzed using modified Region One timber sle cruise progrm. RESULTS A totl of 29 res were surveyed (Tble 1). Stnd dt.--stnds surveyed re mixed, consisting of lodgepole pine, 68 percent; Dougls-fir, Pseudotsug menziesii vr. gluc, 18 percent; Engelmnn spruce, Pice engelmnnii, 9 percent; nd sublpine fir, Abies Zsiocrp, 4 percent. Grnd fir, white brk pine, nd spen compse minor component of the stnd. Hbitt type ves from Pseudotsug menziesii/symphocrpus lbus t low elevtions to Abies Zsiocrp/ Vccinium scopum t higher elevtions (Pfister et l. 1974). Elevtion within the infesttion rnges from 5,35 to 8,2 feet (1,63 to 2,499 m). Infesttion dt.--estimted tree mortlity nd volume loss dt re shown in Tbles 1 nd 2. Averge d.b.h. of infested trees, percent of lodgepole pine killed, nd buildup rtio by yer is presented in Tble 3. A totl of 463,212 trees with n estimted volume of 2,529,244 bord feet (4,15,848 cu. ft.) hve been killed dung the 6-yer peod, 1969 to Size of infested trees rnged from 9 to 2 inches (23 to 51 cm) d.b.h. dung tht peod, verge 12 inches (3 cm) d.b.h. A totl of 51 percent of the lodgepole pine hs been killed in res surveyed. Buildup rtio of old to newly ttcked trees exceeded 1:1 yerly. In 1975, 56 percent of the trees killed were 1 inches (25 cm) d.b.h. nd lrger; 53 percent in 1974; 66 percent in 1973; 87 percent in 1972; nd 78 percent in Approximtely 62 percent of the remining green lodgepole pine is 1 inches (25 cm) d.b.h. nd lrger. -2-

3

4 ra J J sl CD 1 AD N. N 11 CD ra CO CD 11 CD CD st As As AD CD C) r1 AD VI.1 1 J \ ) CO AD 31 CD JJ oi N. J, ra ra VI VD -. op VD 11.1 st CD st st ra M 4. ft ft. OD r4 VD ra CO CO C1 JCm CV CD ui J ch CV CD r1 ch J rl 1l1-1 Ch OD CM ra Ch VD As CD,7 ra st c tr, VD Ch on CO ra CO st C) VD C4 ra r- O1 11 VD N OD ra ul on J CO c CV C) N..D N ch 11,A N. C) ra rl r- ra As ra C4,T c VD 11D un r- CD og. O CO N s 1 VD Ch CO J,A CO C) J J CT Cn ra ri lin In Crn N N 1 AD CN 1 r1,1 11'1 CI C1 CO Ln vi ra r 1 'H st N 11 CO 11.1 VI ul,7 11 Ch N. N C, ra vi ul op 1 As ra N. i - C) Ch N Cm,y. ol.--i N N. Cl r, ra 1. ra Cnt N O q L. q,! L,, - O l- rl cr. ra Cr, 4 '...7 C) N on ra 1 AD CD N ra ra 11 ra rn CD AD VD VD V, r4 NI CO c VD As.. AD OD Ch ra N ra on on cv 1 ch r- C) C) J nt VD n7 r, CV 1 r,.. - ul cd CO,7 OJ CD VD 1 CO C) CD,7 CI Ch CD JO r- ol 1 CD CD I 1 As CO J CV ma st CD C) CD J Ch VD st N..4 ra VD 11 N 1 1D As st C1 ra CD r1. Cm MN. r C) CO 1 1 r CD CD,-I cp st VD As 1 CV I-1 N e-4 AD rn 11 OD r- CD rl.. VD CO AD CD.1 CO VD CD ' ca C).1,4 Cl V1 OD AD J st An,7 1 C) C) ra, QD rl n1 ma r-i ra st.1 CD ON 1D 1D 1 C) 11 CD CD ra 1-.1 r4 r-.1,a 4-1 CD r, 11, n-n *7' M Ch C' 'H 1 eml N..V 111O AD O1 ON Otrrn N ra Io+ Yi VD N. CD C) CD C) CD C) CD CD CD C) C) 11 C) C) 11 un 111 u-) CD CD C) 11 CD r- cm 11 C) VD C) CD st V1 CO CD CD 1,7 1 ra,4 r, ca ma 1,7 CV 1 N M ol rl el o1 cq N. C7,-1 r1 O 1 CD T 4.1, CD 1 ca,t O ij N, W rl r L -cl C %..d-i. o -k X g.. 1 Q ,.bd ILI 'C 1 C 4) NI G.Y.id ).m l s.. 1-n.= n-n I. s-, l 1,1 CU J..--i...y w P-I Le.34 I-,....L3 C.1 '1'1 ( ) - ).. ) I -GI w ;-, G ) c..1. cur u X U > ce u r, X 1..,14 u.a11...w, o. t G ;4 14 CJ L) I,..=,-1 I-, 1:4 q I.., W C4 1.., q A 1:4 1,,- M L C-, C.J' r,), ti.-i ' C.) v. -,,J E.'n!1:1! 3',1' ci Co' s 1' 11 t.,,-4 V, g R. -I 5 Z' E R. ' 71 ":1; t.11 W -I 1-1 l - L. C 6. $.1,-1,*-1 C G..,1 L.. q -.A q U1 O. 3.. C 3.- C.4 o)..-1 FA C 4 v., 3 CD CD CL p4., u z z cn ci tn pl. u1 Ln CD (..1 F.- t..7 F...:C L.) '

5 p u1 CD.7 7 Ch Ch v. ' CD. C) CD ul 7 Ch 7,-I C N- ^4 'PI CD OD VO VD.7 V) CD r- CD 1-4 C) 1 VI 1 AD VD 1 Ul OD CO 3 vl r4.7 V VD V1, 177.4, VD VD VI 1 Ul CV VD,On 7.4 ch A A Om A A A A A A A A A A... A A A A A A A A. CO CV 7 VD C) 7 4D AD OD VI Ch CD VI VT OD 1.4 CV vl p..7 Ul C) 1-4 VD CD CV V.4 C4, r4 CO.. r-i.-i c r-i,--i...-i Tn 1 1 'N Ch C) r-4 csi Cr+ nr,.4.4 AD Ch Cl 1 C VD Ch C4 M VO,4 C) CD.4 ) CV V1 N C. N, Ul.7 V VD 1 7 r, CD VD V CD 1 C. ra.4 1 Ul v) on r,,4 qd AD VD 1 r, 4 c) 4.4 on ca N r, CD md CD -4 4 u1 CD Ch 1 CD A A A A A A A A A A A A A A. A VD Ul C. 1 VI Ul ul. Ch un 1 %JD ra 77 r, CO 1 u1 u1 4 r, ol ol CO n.4 r,.4 cv un CD 1-1 cv un r,.4 CO 4 1 r, Ch VI CO si ch 1 un CD CD ' VD 1 CV VD CD OD CD,N.7 Cn CO ON 1 CD 77 1 CV 4,1 V CO U I' Ch CD Ch ul CV 1 VD u1.4 c) ul cm in Cn,. Cn h. A A A A A A A n A A A A A A A A. A..... CD CD 1 OD 1 VD CD 7 4,1 %.o.1.4 n yl VD try 3 MD rl 1",.1' I-4 --I N,--I 1--1,-I in NN.-4 VD C. CV 1 VD AD 7 ) If) Ln If)... ON 1. A VD CV -I r-i r4 c) 1-4 AD OD V 1.4 e-i 4 i.-4 Col... 1/41 oh..,.. CO...7 ul Ch.1 1 cl s. M tf) ri O gr. 1 CO.4 rn CV CD ul Ch.4.7 VI.7 O CO CI Cr, ij CIA un rn ch,4 r- 11^, rn r- Lin 4 OD C).4 un un V1 ' CD CD N.4 C) CD m C) r, VD ON.4 CD N 1 CD CM CD. VD CV '.7 C. VD CD r, un un N 4) 7 ul 4 N un r, ch ch.4 on r, 4 CD VD CO 1 4 r, ol 1 ul 41 4 CV Cl ra 7 CT C. VI rn 4 C. CO AD ' V1 r- n n.4 N CD un 1. CV Ul 4D CO CD cr 1 CV V17 CV C. r. un 4 c.47 V ul.4 un un rl C4 CO VD 1 on.4 C4 7 r, CO C).4 Ch md ev.4 ( ul.4.4 1,4 CV CO 7 7 CO CO 1 C) 7.7.-I V CO Ul Ch 1-4 VD C) VD.4 Cl VI.7 VD VD U1.4 CD r, r- cv OD c) ol N, 1.I r, r, u1 N...1,) ul.4 c) 4 c ol 1 C) VD Nut nine-in.... In O 1-1 CO E N r- N Cr en C) CV, el CO Ul 1 7 CV ^ rl Ch 4.4 u1.4 r,.4.4 VD r4 1 1 C) Ul r...i ul 1 in O,P4 In 4-1 O, N st, 4 C4 1-1 CD.. ID G W. w -,1 OJ.. CZ.14.. t9 3.1 cl..% CI CD 41 W.-- k >,.. C).n J 1-4 l O C4 C 1-1C C.1G CII.SC 1..% W k X,-I W 5-1 -,-.1 W. 1-,,- Ctl,--, W W tl).a di....x....s ] uhul)...i 1.4 i.. i..) W cv - e k l W c W o W l U q w >, C4 El. D-d ei Z S-I 14 W --I 47 i-, 43 1 G 4) ill >. M t q rle k U A U --,-4 k LI. k k 4.-r-i 3-1 C4 q Ci k 61 d 1-1 O s-, u 4-1 M.1 L) L) OMR. C.),4 1D CJ $.4 (1JJJ C 61 C. M 4-1 7,.1 M 3 W -H ci W..G 3-1 r-i m m.,-.1 W V) 4-1 w MID - M M M Cl. C Li G..L 44 V G Ct. in 44 WG WO.--4M14 W C WW- C., ODW O14 M,4 4.4 [AM n WM. C O OJ...WM14 Cl ZIW 3.M3M1. M 'A 4 DO.3 U LD :: Cw C4 ink on z x Lei m cn, ) cn i:ci 4.) 4. E. CD F...,M C.)

6 Tble 3.--Averge d.b.h., percent of lodgepole pine killed nd buildup rtio by yer, , Glltin Rnger Distct, Glltin Ntionl Forest, Montn. IP Avg. d.b.h. of Lodgepole pine infested trees in killed yerly Buildup rtio Yer inches (centimeters) (percent) old:new in (51 cm).1 1: in. (28 cm) 3.5 1: in. (25 cm) 3.8 1: in. (33 cm) 3.6 1: in. (28 cm) 9.8 1: in. (25 cm) 8.1 1: in. (23 cm) 22.2 Totl or verge 12 in. (3 cm) :2. DISCUSSION The mountin pine beetle hs cused significnt mortlity of lodgepole pine on the Glltin Distct since Tree mortlity incresed stedily through 1972, then shrp increse in number of infested trees (from 18 to 56 per cre) occurred from 1973 to Averge dimeter of infested trees did not chnge pprecibly from 1973 to The pttern of infesttion, i.e., verge dimeter of trees killed nd ccumultive tree mortlity over yers of infesttion is shown in Figure 2. Although this does not show the sme pttern found by Cole nd Ammn (1969) in mountin pine beetle infested lodgepole pine stnds in Wyoming, it does show preference by the beetle for lrger dimeter trees. Entomologists studying other infesttions hve found tht besides tree dimeter, other fctors tht re importnt in governing epidemic infesttions of mountin pine beetle in lodgepole pine stnds re phloem thickness, stnd density, ge, hbitt type, elevtion, nd wether conditions (Ammn 1972; Cole 1973; Sfrnyik et l. 1974). -6-

7

8 Sfrnyik et Z. (1974) used these fctors s bsis for hzrd rting lodgepole pine stnds in Btish Columbi. A similr mp using stnd ge, density, size nd hbitt type ws prepred for lodgepole pine stnds on the Kooteni Ntionl Forest, Montn in Hzrd rtings on the Kooteni were prepred for lodgepole pine res supporting significnt lodgepole pine component greter thn or equl to 6 yers (Hmel nd McGregor 1976). The Glltin Rnger Distct prepred similr mp nd hzrd rted their lodgepole pine stnds bsed on ge, density, elevtion, nd tree dimeter (Figure 3). Mngement poties were subsequently ssigned to lodgepole pine stnds s follows: Poty 1: Highly susceptible; lodgepole is dominnt serl, stnd ge is > 8 yers, trees re 11 inches (28 cm) d.b.h. nd lrger. Poty 2: Modertely susceptible; lodgepole is dominnt serl, stnd ge is >8 yers, trees re 5 to 11 inches (13 to 27 cm) d.b.h. Poty 3: Highly susceptible; mixed lodgepole - Dougls-fir, south fcing slopes; stnd ge is> 8 yers; trees re 11 inches (28 cm) d.b.h. nd lrger. Poty 4: Low susceptibility; lodgepole is dominnt serl; stnd ge is -c 8 yers; trees re < 5 inches (12 cm) d.b.h., nd lodgepole is t the upper end of the size limit. Poty 5: Low susceptibility; ll species over 8,2 feet (2,499 m). On the Glltin Rnger Distct, pproximtely 56,1 cres were ctegozed highly susceptible to mountin pine beetle infesttion. In this re, 2,97 cres (3.7%) re infested. Approximtely 68,176 cres were ctegozed s poty 2 stnds, of which 2,7 cres (3.9%) re infested. In poty 3 stnds, 5,64 cres re susceptible, nd 1,58 cres (28%) sustin current epidemic infesttion. Poty 4 stnds compse 18,627 cres of which 1,148 cres (6%) re infested; however, susceptibility for epidemic infesttion is low. Stnds in poty 5 clssifiction contin 32,18 cres nd only 19 cres (.5%) re infested. Poty 5 stnds re bove 2,499 m nd re low in susceptibility; however, inflight from epidemic infesttion t lower elevtion stnds will result in some tree mortlity in stnds t 2,499 m nd higher. n n -8-

9 Bsed on buildup rtios from 1974 to 1975, nd on the formul Y' = y+bx (Bker 1968) where: Y' = the potentil cumultive number of trees killed predicted through X = number of trees killed in X 1 = number of trees killed in b = x x 1 it is predicted tht 927,781 trees will be infested in 1976, bnging the cumultive kill through 1976 to 1,231,421. This is bout 1:2 buildup rtio of old to newly infested trees for 1976 in the west Glltin dnge. Sufficient crege of susceptible (Poty 1, 2, nd 3) stnds (129,916 cres) occur on the Glltin Rnger Distct to continue the present infesttion t epidemic level for severl more yers. Susceptible stnds mke up 69% of the lodgepole type shown in Figure 3. RECOMMENDATIONS Pst studies (Ammn nd Bker 1972) hve shown tht individul tree control, whether with chemicl or by felling nd burning, will only extend the yers of n infesttion nd cumultive mortlity would probbly be comprble with or without direct control. Methods tht hve been used for direct control in stnds infested with mountin pine beetle re: 1. Tret ll infested trees.--this cn be effective in slowing impetus of the infesttion, but only reduces losses temporly. 2. Logging.--This requires tht every infested tree be cut, removed from the re nd processed por to beetle emergence so stnds djcent to mill yrds do not become infested. 3. Slvge logging.--removl nd utiliztion of ded nd/or trees under ttck by the beetle. Green trees re usully included in these sles to mke them economiclly fesible. 4. Individul tree protection.--usully used in high vlue res. This method requires sprying of ech tree with protective chemicl. No such chemicls re registered t this time. -9-

10 We recommend tht concerted effort be mde to log infested nd susceptible stnds in the Poty 1, 2 nd 3 ctegoes, tht do not hve mngement constnts such s: 1. Spnish Peks Pmitive Are nd proposed wilderness dditions. 2. Inventoed rodless res which would preclude wilderness until Lnd Use Plnning or the EIS evlution is completed. 3. The Porcupine - Bufflo Horn re where mngement prohibits dditionl rod construction. Timber hrvest or slvge must be ccomplished by other thn roding methods except from existing rods. Poty 1, 2, nd 3 stnds tht cn be logged should be reduced to stte of low susceptibility by removing green lodgepole, 1 inches (25 cm) d.b.h. nd lrger. Ded nd infested trees should be removed from high-use res por to beetle flight yerly over the durtion of the infesttion to reduce hzrd to cmpers. S S -1-

11 REFERENCES CITED Ammn, G.D Mountin pine beetle brood production in reltion to thickness of lodgepole pine phloem. Jour. Econ. Entomol., 65(1): Ammn, G.D., nd B.H. Bker Mountin pine beetle influence on lodgepole pine stnd structure. J. Forestry 7: Bker, B.H The use of "buildup rtios" s indictors of mountin pine beetle popultion trends. Insect nd Disese Prevention nd Control, Fire Mgmt., USDA Forest Serv., Ogden, Uth, Office Rept., 6 pp. Cole, W.E., nd G.D. Ammn Mountin pine beetle infesttions in reltion to lodgepole pine dimeters. USDA Forest Serv., Intermountin Forest nd Rnge Expt. St., Ogden, Uth, Res. Note INT-95, 7 pp. Cole, W.E Interction between mountin pine beetle nd dynmics of lodgepole pine stnds. USDA Forest Serv., Intermountin Forest nd Rnge Expt. St., Ogden, Uth. Res. Note INT-17, 6 pp. Hmel, D.R., nd M.D. McGregor Evlution of mountin pine beetle infesttions; Lp, Cool, Lng, nd Cbou Creek dnges, Yk Rnger Distct, Kooteni Ntionl Forest, Montn, USDA Forest Serv., Stte nd Pvte Forestry, Missoul, Montn. Rept Pfister, R.D., B.L. Kovlchik, S.F. Arno, nd R.C. Presby Forest hbitt types of Montn. USDA Forest Serv., Intermountin Forest nd Rnge Expt. St., nd Northern Region, Missoul, Montn. Sfrnyik, L., D.M. Shmpton, nd H.S. Whitney Mngement of lodgepole pine to reduce losses from the mountin pine beetle. Pc. Forest Res. Center, Cndin Forestry Serv., Victo, B.C., Forestry Tech. Rept. 1, 25 pp.

12

13