=r<€/zt fpt-/

FORESTPEST CONDITIONS IN CALIFORNIA 1990

\

\

A Pttblication of the CaLiforntu Foresf Pest Co.uncil

I THE CALIFORNIA FORESTPEST COUNCIL (formerly the California Forest Pest Control Act'ion Council) was founded tn 1951. Menbership is open to pubtic and private forest managers, foresters, silviculturists, entonologists, pathologists, zoologists, and others interested in the protection of forests from danage caused by animals, diseases, insects, and weeds. The council's objective is to establish, maintain, and improve communication among individuals nanagers, administrators' and researchers -- who are concerned with these issues. This objective is accomplished by four actions:

1. coordination of detection, reporting, and conpilation of pest damage information.

2. Evaluation of pest conditions.

3. Pest control recommendations nade to forest managing agencies and landowners.

4. Review of policy, Iegal, and research aspects of forest pest control, and submj-ssion of reconmendations thereon to appropriate authorities.

The California Board of Forestry recognizes the Council as an advisory body in forest pest protection. The Council is a participating menber in the Western Forest Pest Committee of the Western Forestry and Conservat.ion Association.

The reporL, FORESTPEST CONDITIONSIN CALIFORNIA- 1990, is conpiled for public and private forest land nanagers to keep then lnformed of pest conditions on forested land in California, and as an historical record of pest trends and occurrences. The report is based largely on information provided by three sources: (1) the state-wide Cooperative Forest Pest Survey, in which federal, staLe, and private foresters and land managers participate, (2) information generated by Forest Pest Management, Pacific Southwest Region, USDA-Forest I Service, while making fornal detection surveys and biological evaluations, and (3) reports and surveys of conditions on private lands provided by personnel of I the california Department of Forestry and Fire protection. r

This report was prepared by the U.S. Forest Service in cooperation with other menber organizations of the Council. It was duplicated and distributed by the California Department of Forestry and Fire protection.

Cover: Forest pests in California include a wide range of of insects, weeds, plant diseases, and danage fron animals. Each vegetative type and situation. such as recreation sites, has its own complex of potential pest problems.

Sacranento January 2f, 1997

-l-- FORESTPEST CONDITIONSIN CALIFORNIA - 1990

TABLE OF CONTENTS

THE CALIFORNIA FOREST PEST COUNCIL

TABLE OF CONTENTS L1_

HICHLIGI{TS OF PEST coNDrrroNs- 1990

STATUS AND CONTROLOF INSECTS

STATUS AND CONTROLOF DISEASES 18

STATUS AND CONTROL OF ANIMAL PESTS 29

STATUS AND CONTROL OF WEEDS 35

KNOI,{YOUR FOREST PESTS 37 Index of Past Toplcs 39

SURVEYSAND EVALUATIONS 40

FORM: FORESTPEST DETECTIONREPORT 48

COUNCIL AND COMMITTEE OFFICERS 50

-11-

T HTGHLTGHTS0F PEST CONDTTTONS- 1990

The continuing drought was the nost salient factor that affected the forests of California in 1990. Across California, over seven nillion trees of commercial size have died as a result of the insects and pathogens that gain advantage from the moisture stress in host trees initiated and nagnified by drought. In the Tahoe Basin, 800,000 trees, one out of five, have died. Tree mortality continued to be widespread throughout Southern California forests, where the effects of drought are accented by air pollution.

STATUSOF INSECTS. Defoliating insects occurred at endemic levels. Sucking insects, such as aphids and scales, were reported, but did not have major irnpacts in forest settings. Bark beetle attacks on drought-sLressed trees continued into and throughout 1990. All commercial conifer species were represented in the mortality. Losses in numbers of trees and volume have been particularly severe in the true firs of the Sierra Nevada Mountains. Losses in some Southern California pine forests continue to severely deteriorate stand s tructure.

STATUSOF DISEASES.

Dwarf mistletoes and root disease fungi were the nost important pathogens interacting with drought to cause tree mortality. Water theft by the parasltic dwarf mistletoes and inadequate rooL capacity brought about by root disease help create the host stresses that make feasible successful insect attacks. Tree species most affected were ponderosa pine, white fir and red fir.

Dutch elm disease has expanded into the Central Valley. Five trees were confirmed from Isleton, a town 30 miles south of Sacramento. Subsequently, four trees were confirmed in the city of Sacramento, which has a street elm population of 17,500. These are the first diseased elms reported in Sacramento County. A quarantine has been establ-ished in portions of Sacramento, San Joaquin and Yol-o Counties.

Pitch canker was reported as found on planted ponderosa pine near Cabrillo College (Santa Cruz County). This is the first report of pitch canker on ponderosa pine in California. Pitch canker was al-so seen on planted Coul-ter pine in Monterey County.

Hardwood foliage diseases were nore noticeable in 1990 in northern California, presumably as a result of rains in May.

STATUS OF ANIMAL DAMAGE

A variety ofl nammal species caused damage to forest trees. A11 of California's major timber producing regions and timber types reported damage caused by vertebrate species. The majority of damage reported lvas caused by deer, pocket gopher, porcupine, rabbit, and domestic stock. No damage was reported for birds.

-1- STATUS OF IiIEEDS

A fourth year of drought intensified vegetative eonpet,ition 1n much of carifornia and impeded reforestation efforts. Private land managers continue to use a spectrun c,f available herbicides to ensure successful regeneration; neanwhile the U.S. Forest Service has completed a seventh growing season without herbicides.

Figure 1. Attendees at the insect connittee field meeting discuss research examining the potential of populations insect for the selective suppression of competing vegetaLion, Lassen National Forest, May 2J, 1990.

-2-

I STATUSAND CONTROLOF INSECTS

A Report to thn Ca,li,fornln Fweat Peet Corlncil lrorn th.e hwect Cvmrnittee

Don Outen" Chair John V. Dale, Secretary Edtted Uy John l. Daln Deeenber 14, | 990

-3- r STAIT]S AI{D CONTROLOF INSECTS

WESTERNPINE BEETLE, Dendroctonus breviconis.

North Coast. Ponderosa pine mortality increased from previous years, and inciderrce is Uelieved to be a result of the cumulative inpacts of drought. Specific areas of infestation include the area east of Morgan Hill (Santa Clara County), throughout pine areas of Lake, Napa, and Mendocino Counties, and in southwestern Trlnity County. Numerous group kills of fire-injured ponderosa pines occurred in Trinity County. Several groups contained 30* mature and overmature trees. Managenent at Boggs Mountain Demonstration State Forest (Lake County) renoved or targeted for renoval nearly 225 trees attacked in groups ol 2 to 5 by the western pine beetle. Normal stocking levels had become overstocking during the current drought.

Aerial surveillance revealed Coulter plne nortality in southeastern Alameda County. The size of dead trees lndicated atlack by western pine beetles, but Lrees were not observed fron the ground.

Northern. Mortality caused by the hrestern pine beetle increased in nortfiwGtern California. Single trees or small groups of ponderosa pines were conmonly involved, but some groups contained up to 30 trees. Some larger groups of kills also occurred in stands danaged by high winds on the Covelo Ranger District, Mendocino National Forest, and around the edge of the l{ernit Fire, Yolla Bolla Ranger District, Shasta-Trinity National Forest.

Ponderosa pines kllled by h,estern and nountain pine beetles usually r^rere associat.ed with annosus root disease centers on the Devil's Garden Ranger: District, Modoc National Forest. Trees killed varied from the small pole class to overmature sawtinber. Although scattered, nortality was cornmonenough that the total may exceed one tree per acre. Ponderosa pine dyi.ng in the McCl.oud Flats and Pondosa areas (Siskiyou County) usually were weakened by blackstain root disease before they perished.

Sierra. Western pine beetle/drought-related mortality continued at above normil tevels throughout the nnid- to lower-elevation westside pine and mixed conifer stands. Increased levels of mortality were particularly evident in the southern Sierra, especially on the Mariposa and Kings River Districts (Sierra National Forest) and the Tule River, Hot Springs, and Greenhorn Districts (Sequoia National Forest). Mortal.ity occurred as scattered, relatively small, three to Len tree groups as well as large centers of 100+ trees covering several acres. Such large pockets of nortality were reported fron the Deer Creek SOHA (Spotted OwI Habitat Area) on the Miwok District (Stanislaus National Forest) and Lhe Davis SOHAon the Greenhorn District (Sequoia National Forest).

Southern California. As a result of the continued drought and related impacts causea bV smog; bark beetles continue to cause linited but widespread danage on the San Bernardino National Forest. However, insect populations have increased during the spring and sumner of L99O, and larger group-kiIls are expected in late fal-l and the spring of 1991. It is estimated that 210 acres of coniferous vegetation has experienced damage thus far. The San Jacinto Ranger District has a majority of the mortality. The San Gorgonio and Big Bear Ranger Districts are experiencing increasing and scattered amounts of timber

-4- killed by bark beet,les. Approxinately J.l MMBFof tinber trees have died on the San Bernardio National Forest as a resul-t of all species of bark beetles.

Heavy mortality (2000+ t,rees) continued in the vicinity of Mt. Palomar and Julian in San Diego County. Entire Coulter pine stands have been lost, although resj.dual pockets of the blgcone Douglas-fJ.r/coast live oak component remaj-n. Approxinately two-thirds of the nortality is occurring on private land within the boundary of the Cleveland National Forest. It appears that mortality will continue untll a break occurs in the drought. Snall salvage sales are ongoing, but there is a lack of operators.

PINE ENCRAVERBEETLES, Ips spp.

North Coast. Pine engraver activity was prevalent in pine areas throughout the region. fn addition to areas with western pine beetle, pine engravers also attacked Monterey pines stressed by pitch canker infections in Hayward, Alaneda County, and several areas in Santa Cruz County. Other San Francisco Bay Area conmunities incurred pine engraver attacks on ornanental pines likely stressed by wateri-ng restrictions.

NorLhern. Top-killing of pines by pine engravers rdas evident in a few locatior,s in northwestern CalLfornia. Several spots lnvolving at least 30 savrtinber size ponderosa pine were top-killed near Mendocino Pass, Mendocino County. Pine engravers, along with rdestern pine beetle and red turpentine beetle, were responsible for numerous one-acre mortality spots from Trinity to Lake County in ponderosa pine J0-100 years of age. Pine engravers also killed groups of knobcone pine in the Sacramento Rlver Canyon (Slskiyou County).

Sierra. Pine engraver activity was associated wlth nuch of the continued abov5--i-ornal levels of mortality throughout the Sierra (see Western pine Beetle). Pine engraver nortality was also reported to residual pines left after a pre-comnercial thinning of a f to 8 year-old plantation near McCornick Meadows on the caraveras District, Stanislaus National Forest.

Southern California. Species of engravers, along with the leestern pine Ueette, rea turpentine beetle and flatheaded borers, have caused the loss of 3.5 MMBFon the San Bernardino National Forest. Engravers also were active in the losses occurring in the Mt. Palonar, Lost Valley, and Julian areas of San Diego County. Sanitation-salvage crerrs of the California Departnent of Forestry and Fire Protectlon have renoved 2 MMBF of dead and dying trees on private property in San Bernardlno and Riverside Counties.

FIR ENGMVER, Scolytus ventralis.

North Coast. Scattered mortality of white fir occurred in portions of Mendocino, Lake, and Hunboldt Countles. Several grand fir were killed j.n and near Dunlap Canpground in Jackson Denonstration State Forest, Mendocino County. Several attacked grand firs in the nearby drainage of the North Fork Big River were wi-thin centers of annosus root disease. Fi"s in the canpground also were attacked by the roundheadedfir borer, Tetropiun abietis.

Northern. Mortality of red and white fir was scattered, but visibly at nigh leve1s in northwestern California. The fir engraver and Scolytus praeceps were commonly involved in the white fir mortality. Ttre fir roundheaded borer,

-5-

T Tetropiun abietis, and Scolytus subscaber were found attacking red fir. The highest concentrations of both red and white fir nortality were within the lower elevational dlstributions of the species. Mortallty of isolated white fir of all size classes was conmon in the nixed conifer type.

Sierya. High levels of true fir mortality associated with fir engraver activity continued in and around Lake Tahoe. Above normal fir mortality was also reported in nid- to upper-elevation nixed conifer and fir stands on the Pacific and Placervl-l1e Districts, Eldorado Natlonal Forest; the Calaveras and Sunnit Districts, Stanislaus Natlonal Forest; the Mariposa District, Sierra National Forest; and in the vicinity of Breckenridge Mountain, Sequoia National Forest. Poor crown condltl-on, reduced live crowns, and clear pitch streaming on the bole of true firs were frequently assoclated with the mortality.

North of Mamnoth Lakes, Inyo County, scattered dead and dying trees, nostly fir, occurred mainly to the west of Highway 395, Areas with higher concentrations of mortality included the Sherwin Range and Smokey Bear FIat. The najority of tree nortality is inaccessible due to terrain or the lack of a road systen.

SouLhern California. Tree and branch mortality fron this engraver occurred acro3E-T66Jan Bernardino National Forest. Danage increased on the Amowhead Ranger District, but the majority of engraver activity was found on unmanaged lands adJacent to Barton Flats, oD steeper slopes of the Big Bear Ranger District (San Bernardino County), and on the San Jacinto Ranger District (Riverside County). Drought and engravers also were responsibJe for mortality of white fir on private properLy in Rlverside County.

RED TURPENTINEBEETLE, Dendroctonus ventralis.

North Coast. Ponderosa pine in several areas had red turpentine beetle assoEidIEd-TftE attacks by h'estern pine beetle. Monterey plnes with pltch canker (Santa Qruz County) rdere attacked and killed by the red turpentine beetle alone.

Northern. Evidence of attack by red turpentine beetle on ponderosa and sugaF-piieF was widespread ln northwestern California. Both the number of attacks per tree, and the height of the attacks on the boles, indicate that the red turpentine beetle was an important mortality facLor this year. Prolonged drought was the underlying factor responsible for widespread infestations of this beetle. Attacks were nore concentrated in areas suffering from additional stress factors, such as harsh sites, overstocking, or dwarf nistletoe infestation. Red burpentine beetle attacks were very abundant around established black stain root disease centers on McCloud Flats, Siskiyou County. This beetle also was involved in mortality of 2O-year old Monterey pine planted at Lake Mendocino Park, Mendocino County.

Southern California. Jeffrey pine on Barton Bench, San Gorgonio Ranger Ofstrict, and in Crass Valley, Arowhead Ranger District, San Bernardino National Forest, have been attacked to a height of 20 feet. This unusual height is indicative of severe host stress.

-6- FIR FLATHEADEDBORER, Melanophila drunmondi.

North Coast. Borers attacked senescent Douglas-flr at Howard Forest, Uenaoci-.ro Counff. Incidence elsewhere ln the region has declined fron previous years.

Northern. Douglas-firs lnJured by fires fn 1987 and 1988 in northwestern California are beginning to die fron infestations of fir flatheaded borer. Several consecutive years of drought have undoubtedly been a major factor in this nortality. Fir flatheaded borer, in conbination with drought and exposure, has also caused the loss of sone mature Douglas-fir along the edges of several areas that were clearcut in Trinity County approxinately five years ago.

MOUNTAINPINE BEETLE, Dendroctonus ponderosae.

North Coast. Attacks by the mountain pine beetle caused nortality of drougfrt-stressed nature and old growth sugar pine in many parts of the North Coast Range. From Lake County northward to Del Norte and Siskiyou Counties, t-here are numerous areas were it is possible to see fron J to 10 currently dead sugar pines fron a single observation point. Near Mendocino Pass, Mendocino County, mounbain pine beetle also began to kill small groups of suppressed, understory ponderosa pine whlch were infected wlth dwarf nistletoe. A11 five of the identified blister rust resistant sugar pines located on the Mendocino National Forest were treated with carbaryl insecticide during the spring of 1990 in order to prevent attacks by nountaln plne beetle.

Northern. Groups of 20 to 30 sawtimber-size ponderosa pine were killed in tfre a"ea tron Plun Valley Canpground to Benton Meadows, Warner Mountain Ranger District, Modoc National Forest. Drought stress made successful attacks possible. Ponderosa pines killed by nountain pine beetle usually were associated with €rnnosus root disease centers on the Devil's Garden Ranger District, Modoc National Forest. Scattered ponderosa pine mortality in the vicinity of Grass Lake (Siskiyou County) was attributed to the nountain pine beetle and Ips pini.

ROUNDHEADEDFIR BORER, TetropJ.un abietis.

Northern and Sierra. Thls wood borer has been conmon in red fir during the curr@ks1oweronthebo1emaypreceedorfo11owattacksby the fir engraver higher up the bole and in the crown. It was not uncomnon to find red fir with either green or slightly off-co1or foliage. These firs had exit holes ofl the fir borer, and its white boring dust was lodged in bark crevices.

DOUGLAS-FIRBEETLE, Dendroctonus pseudotsugae.

North Coast. About one dozen Douglas-firs at Howard Forest, Mendocino County, attacked by Douglas-fir beetles. Most of these trees al-so were "ere attacked by fir flatheaded borers. A group of four overnature Douglas-firs infested with the Douglas-fir beetle was discovered in a timber sale near Pothole Creek on the Covelo Ranger District, Mendocino National Forest. The infesting beetles were thought to have originated in windthrow resulting fron a

-7-

T storm in Decenber 1988. Evidence of Douglas-fir beetle breeding in scattered windthrow from thls storn has been noted in several locations ln the Coast Rahge. However, only sone of these situations resulted in an increase in Douglas-fir nortality.

JEFFREY PINE BEETT.R, Dendroctonus Jeffreyl.

Sierra. Jeffrey pine beetle nortality was reported as only slightly above normal on the Manmoth and Mono Lake Districts, Sierra National Forest.

CALIFORNIA FI-ATHEADEDBORER, Melanophila californica.

Southern California. This beetle has often been a very important pine pest on ttre San gernarai.no tlational Forest. In 1990 it was a primary cause of pine nortality in Garner Valley, San Jacinto P.anger District, and Barton Bench (Heart Bar Recreation Area), San Gorgonio Ranger District.

EUCALYPTUSLONGHORNED BORER, Phoracantha semipunctata.

North Coast. Thls borer was not detected ln any new counties within the region. ftowever, a new detection was confirmed in Livermore, Alameda County.

Southern California. Applications of traditional forest nanagement principles have reduced problems in urban stands.

DOUGLAS-FIRTUSSOCK lttOTH, Orgyia pseudotsugata. Populations on the Plumas and Lassen National Forests renain at endemic levels.

MODOC BUDWORIIT,Choristoneura retiniana. Visible defoliation of white fir occurred on the Warner Mountain narrger District, Modoc National Forest, fron Benton Meadow to Lake City Canyon (Modoc County). Defoliation was not reported in 1989.

A CALIFORNIA SPRUCEBUDWORII!, Choristoneura carnana californica.

Northern. This defoliator of Douglas-fir has renained at endemic levels since ttre end of the Trinity County outbreak in 1985.

GYPSYDIOTH, Lymantria dispar.

California.

North Coast. Ttre California Departnent of Food and Agriculture applied a ground treatment of dimilin at a Bay-front apartment complex in Marin County in the spring of 1990. This was the Tiburon property where 1/ noths were trapped in 1989. Male moths were trapped in both Santa Clara and Santa Cruz Counties. In Santa Clara County one noth was caught in Los Altos Hills and one in San Jose. In Santa Cruz County one noth was caught in Aptos and one in Henry Cowel1 Campgroundnear Felton (Tables I, II).

-8-

I Northern. Moths were trapped in Nevada, Sacramento, and San Joaquin Counties.

Southern California. Moths were trapped in Los Angeles, Santa Barbara, and San Oiego Counties. One pupal case was found in La Mesa in Septenber 1990. An egg mass survey will be conducted in 1991 in the vicinity of the trap catches that occurred in Santa Barbara County.

TABLE r. CALTFORNTAGypsy DTOTHSTTUATTON - 1gg0a

Properties with Traps Adults Viable Egg Masses/ Sites Years Placed Trapped Counties Pupal Cases Treated

1984 30,000 25 g 2 5 rg95 2B,000 28 10 3 2 1986 27,OOO 20 g 1 0 7gB7 19,000 6 5 1 1 1988 20,000 13 5 0 0 1g8g 21,000 56 L4 2 0 1gg0 21,000 24 I 0 L aAs of August B, 1990.

TABLE II. LOCATIONOF GYPSYIIOTHS CAUGHTIN CALIFORNIA IN 1990

County City

Los Angeles Dianond Br (1), Lynwood (1), Long Beach (1), Mira Mesa (1) Nevada Grass Valley (2) Sacramento Carnichael (3) San Diego La Mesa (4), Vista (2) San Joaquin Stockton (1) Santa Barbara Santa Barbara (4) Santa Clara San Jose (1), Los Altos Hills (1) Santa Cruz Aptos (1), Felton (1)

(#) Number of adult noths trapped.

^b uregon

An extensive outbreak of the gypsy noth was detected in Lane County, Oregon in 1984. The proxinity of this outbreak to California presented the greatest potential to date for the introduction and establishnent of gypsy noth into California. For this reason, Forest Pest Condltions tn California continues to report on the status of gypsy moth in Oregon.

Status at the end of the 1989 Season. In 1989, approxinately 22,250 gypsy noths traps were placed statewide. 0n1y two gypsy noths were detected, about three niles apart in Euguene, Lane County. This was the fewest caught in the state since 1979, the year gypsy noths were first detected in Oregon. No Gypsy

-9-

I noths were caught in Lake Oswego, Clackamas County -- the only site receiving eradicative sprays of Bacillus thurin8iensis in 1989. For the first tine since 1980, no eradication programs were planned for 1990.

1990 Survey Program. Approximately t6,335 traps were placed statewide. efong 11,680 detection traps and 3,755 delimitation traps, 9OO additional delimitation"itt, traps were added in response to ner4rgJapsy moth detections. As in previous years, gypsy moth survey and detection traps r^rere concentrated in western Oregon, where most of the suitable habitat and population centers occur. The standard detection trap density was 1-4 traps/square nile. Delimitation trap densities of 16-49 traps/sq ni r^rere placed at all 1989 detection sites, and were used to monitor previous eradication areas. No nass trapping was done in 1990. Special si-tes such as state and national parks, public and private canpgrounds, and RV parks were also trapped.

Nineteen gypsy noths were detected (Table III). AII detections were in west,ern Oregon; only two traps had nultiple catches. Detections were nade in nine general areas from north to south as follows: Warrenton (two moths in one trap), Hil-lsboro (one moth in one trap), West Portland (two single noths in two traps), Lake Oswego (four noths in one trap, plus four scattered singles), Estacada (one moth in one trap), Eugene (two single noths in two traps), Rogue River (two single moths in two traps), and Cave Junction (one moth in one trap) (Tab1e III).

The two gypsy moths in Eugene were caught about a mile southwest of each of the two single detections made there in 1989. Over 19,000 moths were detected in Lane County in 1984, and the 1990 trapping reflects the success of the earlier eradication projects in combination with the detection and delimitation trapping programs. About 6,000 traps were placed in Lane County this year. The nultiple detection in Lake Oswego (four moths) is about t/3 nile northeast of the 1!8! eradication area. This is likely to be a new introduction site as several new residents fron the northeast have been identified in the innediate area.

Projected Eradication and Survey Programs in 1991. Additional surveys of recenL arrivals from the Northeast and subsequent egg nass searches are planned at up to five sites where new detections were made: Cave Junction, Estacada, Lake Oswego, Rogue River, and Warrenton. Any eradication programs for 199t will be based on the results of egg tnass searches and detection data in those areas. Eradication programs would likely be less than 640 acres and use Bacillus thuringiensis applied from the ground. A reduced trapping program is projected for 1!t1 because most of Lane County has been free of gypsy moths for four years. Delinitation trapping around all 1!!0 gypsy moth detections, and any eradication sites, will supplement the usual survey program.

Eastern United States.

Estimates of defollation by the gypsy noth in 1tt1 exceed 7 nillion acres -- a 4 nillion acre increase over 1989 and nearly 6 nillion over 1988. This may result in increased detections of gypsy noth by the California DepartnenL of Food and Agriculture in 1!t1 or 1992.

- IU- Table III. Summary of 1990 Gypsy Moth Detections in Oregonb

County City/Area Total Males Caught Trap Density

Clackamas Estacada 1/sq nt ( increased)

Lake Oswego 15lsq ni ( increased)

Clatsop Warrenton 2/sq nl (increased)

Jackson Rogue River 1/sq mi (increased)

Josephi-ne Cave Junction 1/sq mi ( increased)

Lane Eugene 16-49/sq ni ( increased)

Washington Hillsboro 4/sq ni

Raleigh Hills, W. Portland 4/sq ni (lncreased)

Sylvan Hi11s, W. Portland 4/sq ni ( increased) StatewLde total 19

bs,rbriar.d by AIan D. Mudge, Oregon Departnent of Agriculture, 635 Capitol St. NE, Salen, 0R 97310-0110

GMSSHOPPERS,Acrididae.

Sierra. A detection report fron Tuolunne County indicated that Jeffrey pi-ne and wtrite fir plantation saplings 3 to 6 ft in height were danaged by short-horned grasshoppers. In the same county low levels of feeding injury were observed in two, 7-year old ponderosa/Jeffrey pine plantations on the Calaveras District, Stanislaus National Forest. No damage was observed on nearby one to two-year old plantations. The potential for significant grasshopper damage is recognized by the Groveland District, Stanislaus National Forest, in the large, often contiguous areas, that need to be regenerated following the recent fires.

C0NIFER APHIDS, Cinara spp.

Sierra. Aphids continued to be abundant, but not at the levels of 1989.

-rl--11

I TENT CATERPILLAR, Malacosoma sp.

Sierra. Low to moderate levels of defoliation on antelope bitterbrush were reported along Highway 89 between Truckee and Sierraville (Nevada and Sierra Counties). Tent caterpillar activlty renaj"ned low in the Mommoth-Mono Lake area (Mono County).

SEQUOIAPITCH UOTTI, Vespanlna sequoiae.

North Coast. This insect continues to be a pest of ornanental Monterey pine tfrrougtrout the region.

CALIFORNIAOAKIIOTH, Phryganidia californica.

North Coast. Defoliation of coast live oak occurred in a few locales in Santa Cruz County.

FALL WEBWORM,Hyphantria cunea.

Norttr Coast. Webbing and associated defoliation of Pacific nadrone were note-d--li-E6ieiEl areas of Santa Cruz County and in the Brooktrails area near Willits, Mendocino County.

BALSAII{fiilIG APHID, Mindarus abletlnus.

Sierra. This aphid probabl-y was responsible for damaged terminals and buds on aFpi6*hately half of the white flr seedlings planted along with Douglas-fir over 20O to 25O acres of the Oroville Ranger: District, Plumas National- Forest, Plumas County.

Research on life history, danage, and suppression continued into the second year at Placerville Nursery, Eldorado County. Collections subnitted to a specialist at the Illinois Natural History Survey indicate that the species nay be Mindarus victoria, and not M. abietinus.

SPRUCEAPHID, Elatobium abietinum.

North Coast. Continued attacks keep foliage sparse on planted roadside sitka spmce south of Eureka, Humboldt County.

MATSUCOCCUSSCALE, Matsucoccus sp.

North Coast. One to two dozen ponderosa pine in and around Loch Lonond, t atce-Eoilntir, ftad branch flagging sinilar to that caused by Matsucoccus scale. Only a few larvae sinilar to Matsucoccus were recovered from twig bark and ldentlfication h'as not concluslve. However, thls area has had danage fron MaLsucoccus in the past.

-12- OAK PIT SCALE, Asterolecaniun ninus.

North Coast Most samples of branch decline of coast live oak fron niprdffio had twig danage fron oak pit scales. Linited sampling of oak branch flagging did not allow an accurate delimitation of oak pit scale incidence.

A GELECHIID LEAF SKELETONIZER,Chionodes trichostola.

Northern. Larvae of this noth caused widespread defoliation of blue oak around ttre Sacramento Valley, especially Shasta and Tehama Counties. The l-arvae skefetonize the leaves, causing them to turn either partially or completely brown. There is one generation per year with nost feeding damage being completed by the end of May. The majority of trees maintained their original conplinent of leaves, albeit danaged, through the summer. Only the most heavily damaged trees refoliated. Although some locally severe defloliation was observed, little or no tree mortality occurred.

AN OAK LEAF GALL MIDGE, unknown.

North Coast. This was the second consecutive year of leaf ga11s on black oal*s rtear Ukiah, Mendocino County. Damagewas also noted on black oaks at Lake Pillsbury, Lake County. In the Ukiah infestation, there lvas an average of 4.] ga1ls per leaf throughout the crowns of infested bfack oaks. Attempts at noanino fha 1an.7sg for purpoSes Of adult ident,ifiCation were UnSuCceSsfUl.

ASH WHITEFLY, Siphoninus phillyreae.

Southern and Northern California. Also known as the pomegranate, pear or peac in California in Ju1y, 19BB on heavily infested ash trees in the San Fernando Vatley area of Los Angeles County. New county records in 1990 extend the general distribution to 35 of the state's 58 counties (Figure 2).

-13-

I CHRONICLEGP,APHIC

Figure 2. California counties with at least one collection record of the ash phi11l're-ae, since the originat derection in Los Angeles uounty:lt_t:tt{' 9*P1!H ln 19ud. (From: Gill, R.J. 799O. The Ash whitefry in California. Cal' Dept. Food & Agr- 14 p., updated Decenber 24, San FrancisJo Chronicle.)

-14-

E TABLE Iv. INSECTS oF LESSER IITIPORTANCEIN CALIFoRNIA . 1988

INSECTS WHEREEXAMINED OR REPORTED Scientific Name Connon Nane Host County Remarks

Adelges cool-eyi Cooley gall Siskiyou Galls on twigs near aphid Knopti Creek, Gasquet R.D., Six Rivers N.F.

Altica ambiens alder flea hrA Trinity & Defoliated alder on beetle Shasta Willow Creek, Grass Valley Creek, Coffee Creek, and Trlnity Lake. AL Eldorado SmaLl number of trees on private land.

?Bucculatrix Oak ribbed- Nevada Leaf skeletonizer. afUertieffa case maker

Calophya schini Peppertree Contra CDF&Areport psyllid Costa

Cleridae Checkered Tuolumne Commonbark beetle beetles predators.

Collops sp. A soft-winged Humboldt Found under bark of flower beetle dead saplings, probably secondary.

Cylindrocopturus Reproductlon PP, Butte Both species appeared eatoni and C. weevils DF in a mixed, 5-6 year furnissi old plantation.

C. eatoni Reproduction PP Trinity Plantation C. furnissi weevils DF Sonona Christmas trees.

Cynipidae Cynipid ga1l OA Calaveras Injury to foliage. wasp QW El Dorado Injury to foliage.

Dioryctria sp. A pyralid noth DF Butte Christnas trees

Halisodota Silverspotted WF Tehana Defoliated 0.5 to 1 argentata tiger noth acre on Croney Ridge. PP Trinity Incidental co]lection fron plantation tree.

Neodiprj.on sp. Pine sawfly PP Lake Sapling trees.

Neophyllura Madrone psyllid MA El Dorado Most were arbuti parasitized.

Nuculaspis Black pineleaf Santa Vandenburg AF Base californica scale Barbara

-15-

I TABLE IV. (Cont. )

INSECTS WHEREEXAMINED OR REPORTED ScienLific Name CommonNa-ne Host County Renarks

In 2-O Douglas-fir gtiorhynchus-sulcatus Black vine DF Hunboldt weeviL beds

Present at Chico Tree -Platynota Omnivorus DF, PP Butte stgftana leafroller GS Inprovement Center.

Pseudopityoph- Western oak 0A Riverside & Widespread in oak thorus bark beetle San Diego stands pubipetrttis

?Puto cupressi Fir nealybug DF Tuolumne 0n plantation saplings.

scolytus A Scolytus bark DF Butte christnas tree praeceps beetle Plantation

Scythropus sp. A pine needle PP, Placer & Light danage in weevil JP Riverside Plantations.

Sterennius sp. A root-collar PP Shasta Very minor danage. weevil

St,omacoccus Sycanore scale PA Marin CDF&AReport platani P0 San Mateo CDF&AReport

Trisetaeus Pine bud mite SP Lassen Only a few trees ehmanni involved.

Unknown Cutworm DF Hunboldt Danage linited and scattered in 2-O Douglas-fir

Unknown Leafhopper BM Shasta, Leafhopper abundance Siskiyou, associated with & Trinity severity of leaf scorch.

Unknown Scale MA Amador Widespread on host within the nixed conifer type.

Xanthogaleruca Elm leaf beetle HW Plunas Residential trees. luteola

Xylotrechus Oak cordwood 0A Mariposa Very common on a nauticus borer residential property, abundance probably was related to drought stress.

-16-

E HOST ABBREVIATIONS

= nL- Alder BP Bishop pine BS= Brewer spruce BM = Bigleaf rnaple lldtlOltC-T1n EU = Eucalyptus spp. Lr:) = Giant sequoia HW = Hardwood Jeffrey pine MA = Pacific madrone 0A= Oak PA = London plane PO= American plane PP = Ponderosa pine QA= Coast live oak QD = Blue oak nl.l - Interior live oak SM = Peppertree SP= Qrrqan ninp WA = White alder t^lF - wn].te r 1r

F'isrrre ?- Attendees at the insect field comrnittee neeting discuss baiting with bark beetle pheromones to Protect leave trees from successful attack by bark beetles, Roseburg Resources, Shasta County, ttlay 2J, 7990.

-17 -

I STATUSAND CONTROLOF DISEASES

A Report to the Cd.liforntn Foreet Peet Council lron the Dil'eose Cortmittee

Melisec Moro*y, Chuir Ti'rn TiduelL Seereta:ty Edtted b3l Suson Fro;r*el Decentber | 4, 1990

- l8- r S'TATUS AND CONTROL OF DISEASES

ABIOTIC DISEASES.

l,krre than seven million trees of commercial size irave died in Calif'ornia during the cr.rrrent drought. Alt.hough mortality generally leas scaLr--ei'ed as individual Lrees or small €iroups n ext ensive mortal it-v areas sorneLjmes t:xt.errded to I 50 ilcres. In the Tahoe Basin, 800,000 trees, or. or)c c-if every five, harze dicd. 'free mortality occurred througirout Southr:rn Calj.fornia florests. Exceptional,ly high 1e','e1s of mortalit.y we-rrefotrnd in t..he Mt. I'alcr:rar. LosL Va1.iey, and Julian areas of San Diego County.

California experienced excepbional 1y cold LCrnpl'ps1u1'.tdrrr:irrg laF.e l)ecentber, 199C. Da.mageLo native vegetatiorr should be minirnal unless planted well out of tl'o nrr r'rra nrnl€. Ilowever, exoLic vegetilLiorr was severely af fected in soule locatiorrs. It will be splr'ng before ti-re irnpact can be fu111'deLr--rmined.

AIR POLLUTION. The aniount of visibl.e fol iar ozone in j rrr5, t r; 1>ines in Lhe souLhern Sierla Nevacla has decreasecl over Llre 1as;t- 1l yoors . l'his corncicles ,.,i I h o n^nir'rt ^fl dr.ougltL st.r.ess whi ch 11ir.ycarrsc pondcrosa arr,l .),:f f n

FOLIAGE DISEASES. Oaks in Trinity and Siskiyou t:orlntieii were af fect.ed by Sept.oria leaf sprct. Calif,ornia black oaks were partiall.v defol j ated by Scptoria dryina jn mar)y areas, but especially along the fllanrath and'i'r'inity Ri"anslnd around Clair Engle Lake. Oregr,rn whj te oaks in l{a;';6pp Val1ey /Tlini+rr t/rnrrnF,--*.. -y ) were severely af fec t-ed by an rlndeterm i r)o(l species of 'l'he Sclptoria" increased amount of L:af spotting in t.he two corrnly area \rr

SIiqrnina thujina was ldentified from PorL-OL'ford-ceditr on Freirclr Hi1,l , Gasquet nangc" Dlstrict. Six Ri.,,ers Natiorral l.-orest (De1 Norte Count-.v) . 1'l'ris is the fi.rst record of the disease on Port.-Orflord-i::erlar wltl'rin its native ranse.

T'here has been little change in tlri: i nc j den,.:e of' othcr coni. fer fol iage diseases. El_ylfgqggrng deformale caused h'lgh15' r'isible darnrage;erlong certain roadsides and Rock Creek on t.he Mlnarets Rarrger. Dis tricL , S:ierra Nartional ForesL (Madera Courrt.y). R!$!oS!t_t'g rpp. on DougLtis-fjr arrd Scirllria pini and \g{C1:Jgf"t rp. on Morrterey pine were incjderrtal. Incidence' of lltqglyplepLtg garinral)nion Dorrglas-f i r. near Arcatc (Ilurr'bo1d,;Cor-rrrr y) has srrlrsidcd.

pd lnfostaticrns hv Car.r-nqrrnnplvvr vv"Hvr v1 1le u tninhrrnhi I n in'i ti nt nrpmAf rrrF dei'OliaLiOn Of' 'l'rini Orcgon as,h in t.he Coffee Creek area of cy Counly.

Maplc tal spot (!b!i_s;1rlq acer:inrrm) infccted rrrrrple alorrg Hock Cleck liuLure I'rai1 (Nevada County) . This fur-rgus caLrses a riittrcf slrowy, but irarnlr:s:: spol- on natple leatzc:s .

-1q-

I NURSERY DISEASES. Disease problems at Humboldt Nursery (I{rrmboldt Cour':t1') included: Sirococcus strobilinus, a cause of tip blight, rleformed and killed 1-O Jeffrey pit.e; gr.y -old- car.rsed by Botr),t_is sp., produced tip djeback ot' redwood seedlings and loss of lower needles in Douglas-fir:; cedar leaf blight, caused by Didymascella (59_f$:g) thujinq, was responsible f'or foliage 1,rss arrd mortality of 2-0 western red cedar; and Septoria sp. caused a leaf spot of rr:d alder. Powdery mildew defoliated 10,000 bigleaf maple seedJ-ings. Tlvo thousand white alder seedlings were infected with a rust, most likely llelg4parryc]191 a1ni. Dothistroma pini, the cause of red band needle bligitt, &ttackerl app"o*inmtet-V f ,OOO t-t ponderosa pine seedlings.

At- Placerville Nr:rsery (El Dorado Corrnt5'), Fusarirrnr spp. causcd sca.ttelt:rf mort-ati.ty and chlorosis of 1-0 Jef f re.y pine. Seerllings werc prcdisposecl to disease by overf'ert.ilizat.ion and hot weaLher-. Sun scorch caused damage to lower needles and scattered mortality of 1-O Jeffery pine.

At Magerlia Nrrrsery (Brrtte County), Frrsariurn spp. continued to kill 30 to 40% of the sugar pine, red f ir, and whj te f ir in rinfumigat.ed areas " Mort.alil-y w.rs between I and 1,0'/"on fumigated and experirnentally treat.ed so:i.ls" Charcoal roc.rL disease (caused by Macrophomjnq phaseolina), a new disease aL this rrursery, \{as found on giant sequoia (9ggggigqg1qlel gir!!1{_euq) .

Fusarium spp. caused rnortality in 1-O Douglers-fir at the Chico Tlee frlpro'remenr- CenLer (Butt.e County) . Losses due to Ftrsar:.um spp. and olher rrnknowrr cal.lscs were sustained in 1-O ponderosa pine, 1:O ;iigai' pine, 2-O sug:rf pine, and 2-O Douglas-fir. Gray mo1,ddamaged 1-0 giant sequoia, brrt nrorLalit.,,',ras ljrnit.cd b.1, fungicide treatnrenL. Pgllyllg sp. also dantag;ed coastal redwood trt. Lhe L. A. Moran Reforestation Center (Yolo Countv).

Phoma sp. caused mortality in giant sequola and rvhite fir at Bcn l,onrond Sbate Forest Nrrrsery (Santa Cruz Corrnty) . Phytopht.hora spp. af so car.rsed nrj nor- Losses of white fir.

ROOT DISEASES.

Black Stain Root Disease (caused b.y L,eptographium wagoneli ) . St-ands of ponderosa pine near Pondosa (Siskiyou County) were reported Lo have black slairr infection centers. Near Viola, Shasta County, approxi.mately 30 infect-crl ponderosa pine trees were scattered across 2 acres of prirrate Iancl. An additional center in Shastri County was located in a ponderosa pine stand jusl west ofl Day Iload and Big Valley Mor.rntaln. North of Covelo. irr northeiast.r:rn Mendocj no County, bf ack stain was seen irr pondelosa pine, tl're f -ir:st f ind of black stain in pine in It'lendocino County.

Severaf Dor-rglas-fir plantations on the Mad Rirrer and Orl.eans llarrger DisLrjcts, Six Rivers Nal-ional Forest (liumboldt and Trinity counties) also had i.nfection cerrters. Many scattered Douglas-li r rreaf Ruth Reservoir, Tr-iniLy Co. , were declining f'rom black stain root disease. A few of these t-rees were attacked t-ry the Douglas-fir beetle. Concern continued about this disease jn Douglas-fir and its relationship to precommercial thinning.

Port-Orford-cedar Root Disease (car-rsed l,y Phyt-ophthora lateralis). frr Califor-nia, Port-0rford-ceda" .oot disea-te-ret alns fini tcA-t.; ll'e S"r th Rjver drainage (Del Norte courrty) and a few small infections on the Siskiyou Nalional Forest. A new infect.ion area r,vas i

-20- sale is being considered on the Gasquet Ranger District. An eradication attempt on a tributary to the Middle Fork of the Smith River near Sanger Peak, Gasquet Ranger District, appears to be successful thus far. No infected trees ldere observed downstream 20 nonths after the operation. Dead €tnd dying Port,-Orford-cedars near Cedar Canp, Ukonom Ranger District, Klamath National Forest (Siskiyou County) were infested with Phloeosinus bark beetles, but were notinfectedwithPort-0rford-cedarrootai@1ateraliswas isolated from discolored stem tissues of Pacific yew on the Gasquet Ranger District. This is the first report of Phytophthora lateralis on Pacific yeh,. Tests to determine the degree of susceptibility of this tree species to the fungus are in progress.

Annosus Root Disease (caused by Heterobasidion annosum). Annosus root Oi,se ation, Hat Creek Ranger District, Lassen National Forest (Shasta County). This plantation was planted in 7985 after the site had been harvested and prepared for planting. Site preparation included stump removal. A group of about 12 ponderosa pines was observed to be infected and dying. Small pieces of root material fron the previous stand were found in the soil where mortality was occurring. Annosus root disease also caused nortality of giant sequoia (40 ft, t2-16" dbh) on property of the Saint Germain Foundation in Dunsmuir (Siskiyou County). Several adjacent, row-planted incense-cedars had been killed in previous years. and it appeared the fungus hras spreading underground through rooL contacts. This root disease also occurs in scattered locations on Mc0loud Flats (Siskiyou County).

Annosus root disease contributed to windthrow scattered over 40 acres of mixed-conifer type on the Downieville District, Tahoe National Forest (Sierra County) at a rate of 6 to 12 trees per acre. Infected trees often hosted Armillaria root disease and the fir engraver, but these pests were secondary. Annosus root disease continued to predispose grand fir to attack by the fir engraver beetle in the North Fork Big River area of Jackson Demonstration State Forest (Mendocino County) .

A 5O-foot strip was cleared of all host trees around the perimeter of a very Iarge annosus root disease center on the Manmoth Ranger District, Inyo National Forest (Mono County). The project was an attempt to stop the spread of root disease into a pure stand of Jeffrey pine in the pole and small sawtimber size classes. A11 stumps were treated with borax.

An incidence survey for annosus root disease was completed in t eastside pine type timber sale areas on the Mono Lake Ranger District, Inyo National Forest (Mono County). The survey focused on finding conks in stumps to determine infection frequency. No root disease was found in one area that was pure lodgepole pine. Stump infection varied fron 27% to 5Ol in the other four areas that r^rere predominantly Jeffrey pine. All of the sites had been logged at least 10 years previously.

Damage from this disease continued to contribute to mortality of conifers on the San Bernardino National Forest in Southern California. The disease was confirmed as the agent responsible, for the mortality of a small population of giant sequoia trees in the vicinity of Snow Valley Ski Area. Other plantations of sequoia are being monitored.

Armillaria Root Disease (caused by Armillaria sp. ). Armillaria killed seve" n State Forest (Lake

-2L- County). The surrounding ponderosa plne saplings were not affected. A group of several tanoalcs and one large Douglas-flr were killed by this root disease at the Mt. Hermon Conference Center near Felton (Santa Cruz County).

Laninated Root Disease (caused b . Ttris root disease hras iaen River Ranger District, Klanath National Forest (Sisktyou County). An opening of two to three acres has been created Ln this white fir/Douglas-fir stand. Additional scattered nortality and windthrow also are present in the stand.

CATIKERDISEASES. Pitch canker, caused by Fusariun subglutinans, continues to infect Monterey pine in both Santa Cruz County and Alaneda County. Some of the noderately to heavily infected trees were klIIed by pine engraver beetle and/or red turpentine beetles. Pitch canker has now spread one to two nlles northward of.the Santa Cruz city linits along Htghway 1. Pltch canker also appears to be intensifying in the Watsonville area (Santa Cruz County) according to the local Farn Advisor. Detections in other south bay area countles are unchanged.

Pitch canker was reported on planted ponderosa pine near Cabrillo CoIIege (Santa Cruz County). This is the flrst report of pitch canker on ponderosa pine in California. Pitch canker was also seen on planted Coulter pine in Monterey County.

Pitch canker research at the University of California, Berkeley indicates that pitch canker appears to be intensifying in the Santa Cruz area (M.8. Schultz, T.R. Gorden, and A.H. McCain, personal communication). Their findings are based on pruning studies. One hundred new infections were identified on trees in which all observable infections had been removed the previous season. The complete epidemlology of pitch canker is not understood and it is unknown tf these infections were undetected prior to pruninS, or if they occurred in 1!!0.

Cypress canker, caused by Serl.diun cardinale, was noted in one ornamental redwood in lJkiah, and in a few drought-stressed Monterey cypress near Hopland (Mendocino County).

Although sanpling of branch flags on oaks rras linited, oak branch dieback, caused by Diplodia quercina, apparently intensified on coast live oak throughout nost of California. The oak pit scale occumed ln conjunction with these infections.

Madrone canker, caused by Fusicoccun aesculi, (Leleonorph = Botrysphaeria dothidea) was prevalent in most counties in Northwestern California.

Branch and stem infections caused by Bobryosphaeria ribis continue to kill branches and tops of giant sequoia planbed on dry sites at low elevation. Infections have been noted in Napa, SonoDa, Mendocino, and Humboldt Counties. The fungus is also contributing to declLne of chaparral species including manazanita, ceanothus, and Tecate cypress in Riverside and San Diego Counties. The plants are predisposed to fungal infection by drought, air pollution, and other undeternined environnental stresses. The dead brush plants pose a severe fi-re hazard.

DWARFUISTLETOES, Arceuthobium spp. The abundance and distribution of dwarf nistletoes change only gradually over tine. Nevertheless, dwarf nistletoes are

-22- f requentl.y f actors that lead to decline and mortality of rl,nfected trees. Such Has the situation iu 1$!0 when urortality and abundant branch flagging occurred throughout the central and southern Sierra Nevada on red fir and white fir irifecled wit.tr dwarf mistletoe. Drorrght stress, at-tacks by Scolytus bark bec:tles, and infecf.ions of Cyt_o_s_porag!_Lelie (the cause of cytospora canker) were contributins factors.

Brewer spruce near: Baldy Mountai-rr, Happy Canrp Ranger: DistricL, Klamath National Forest (Siskiyou Courrt-y) were heavil,y broomed by dwarf mistletoe, probably white fir dwarf nrlslletoe (Arceuthobiuq gf_fglilUm f.sp. concolqris). Also on the Happy Camp Rangel DistlJct, DougJ.as-fir dwarf mistletoe, Arceuthobium !g9g_] att_i, and white f ir dwarf mistletoe are adversely i.mpacting stands in DooliLLle Creek drainase.

lnJestern dwarf mistletoe (Af.Sgqgqr_gq qggpylglgglg) was associated wj th rnortality of ponderosa pine on the Covelo Ran5;er District, Mendocino Nat.ional Forest (lt'lendocino County). Western dwarf mistleLoe continued to spread slowly in ponderosa pine at Boggs Mountain Demorrstration State Forest (Lake County).

Efforts 1-o survey Nationa-l Forest lands infested wittr dwarf mistletoe were rntensified in 1990. Pt'e-srrppression surveys were conducted on over 600O acres cn t,he Ange1es, Cleveland, Inyo, Los Padres, Mendocino, Plumas, and San Bernaldino National Forests, with plans to survey an additional 2100 acres on tire Angeles, Cleveland, Klamath, Inyo, Los Padres and Mendocino National Forests in 1991. Treatment of over 6500 acres on the Angeles, Cleveland, P-Lunras,and San Belnardino Nabional Forests is plernned f'or I99I .

A dwarf rnist.l.etoe suppress,ion project was implement-ed on Newhouse Ridge, Covelo Rarrger District, Merrdocino National Forest (Mendocino County). The objective ri.ras to protect a 4O-acre plantation of ponderosa pine from infect.ion by arr o!'erstufy source of vresLern dwarf mistletoe. Pheromones of the western pine beeLie (lg:lQfoSlglllle !fg"l!.,Uf ) were applied to target trees to attract tlee-killing insects in ordel to kill the infected overstory pines. Any trees {"'11'/ rrrjt. >u(_('L:i5t \/ Lr-) attacked and killed will be either gir:dled or felled in 1!!1"

A r-,lv;:,rtrfmistletc-re plr'e-supi)r'ession survey ',ras conducted in Twin Lerkes Cantpg-round, cn the illammoth )iarrgel Di strict , Inyo National Forest (Mono C,:. ) . Dat:r r:oilecLed I'ronr the Jli-acre carnpgfound wilI be used to clecide which t.l-eal.tirr,:trt or conrbination of treaLnrents ar.'e feasr-b1e for the Lreavily infected sj.trj" If a. cont-rol project de:velops, it will be the first suppression project j I tliat tar-geLs I odgepole pi ne dwar,f rnistietoe n Cal ifornia. I t1

l nlJSf DISEASIiS. Idhite pine blister' rLrst (caused by glgg_f!1fiq ribicola) r-:ontilr'.red to affect sugar pine in Cal.ifornia. As efforEs to identify and protect resistant sugar pines acceleraLe, one of the six known homozygous lesj.sbanL tfees irr the state succumbed to att.ack by the mountain pine beetle (.P_g1_d11gq_!onousqe!_qglgqae) in September. The tree's genotype tras preserved by gral'ting. Ottrer resj-sterrrt trees on Lher Stanr'slaus and Sequo:ia National- Forests ltave been attercked bv bark beetles and ace faclirrE"

Thirty-six sugar pines resistant to wl-rite pine blister rust have been identif ied in the southern Sierras on Itlountain Home Demonstration State 'Iirree Forest. a'-'e holnozygous (RR), while the remainder are heterozygous (Rr) for nra.;ol' €lcr)e resistance (MGR). A toLaI of 161 sugar pines (known resistant

-)'7-

I and candidates) were sprayed twice wi.th carbar:yI (Sevin 80S) in 1"p$0 to protect against attack by red t.urpentine and mountain pine beetles.

Eleven heterozygous resist,ant sugar pine have been j.dentified in the northern Sierras on Lal-rcur Demonstration State For:est. A total of 136 trees (knowrr resist.ant and candidates) were treated once in 1990. No protected trees have been kil-l-ed in either forest by bark beetles since spraying was first begun in April of 1989.

Five white pine blister rllst resistant sugar pines on the Mendocino National Forest were sprayed with carbarl'l to protect then against attack by mountain pine beetle and red turpentine beetle"

White pine blister rust caused incr"eased leve.tr-s of branch flaggi-ng of sugar plne on Mt. Sanhedrin, Lake County. Areas of infect,ion appeared in or near areas burned in the 1987 Mendenhall fir:e. Growth and abundance of alternate hosts (81!9-.1spp. ) of the fungus have irrcreased in the area since the fire.

Western gal-l rust, caused by Periderni-um harknessii, degraded ornanental plantings of Monterey pine and-natirre* stands of knobcone pine in Sonona Cr-runty. Branch mortality and stem cankers occur in these and several other pine species.

yglql_Igst Diseases. Several l-esser-known rust diseases were reported in 1990. Fir-fireweed rust carrsed necrr:sis of current year lvhite fir needles on more than 100 trees on private forest l-ands in Siskiyou County. Pucciniastrum _e$leLi! causes the rust. UglggpgglgUg @, which causes yello* witches broom of true fi-r, infected 5 to 10 trees per acre on 26 acres of the Sierr:avi11e DisLrict, Tahoe lrlaLional F'orest (Sierra County) .

Douglas*fir rust, caused by Melampsora riedusae, was found on saplings on private land near Quincy (Plumas Cr-lunty). The alternate hosts of this rust are cottonwood or poplar. The rust. crruses needle necrosis and discoloration, which usually results in ninor damage. Blueberry rust, caused by ru9g1rc!ry gorqperlrgnqq, infected end ruined several hundred white fir Christmas trees west of Willjts, Mendocino County" The alternate host in the vicinity is black huckleber:r'y.

DUTCH ELIII DISEASE. Dutch e1n disease, caused by qe_Iglggy€_t€ ulmi, has expended intr: the Central Valley of California. F-ive trees were confirmed from Islet,on, a town 30 nj1es soulh of Sacramento. Subsequently, five inflected trees have been confirmed in the city of Sacramento, which has a street elm population of 1/,500. These are the first diseased elms reported in Sacramcnto County. A quarantine has been established in porticns of Sacramento, San Joaqui.n, and Yo1,oCor.rnt.ies. (See Sur:veys and Evaluations" p. 43)

-L'a-rlr

I TABLE V. FORESTDTSEASES REPORTED - rgg}a

ABIOTIC INJURIES

Air pollution JP Kern, Fresno, Tahoe

Drought AIl species Statewide

FOLIAGE DISEASES

Cercosporella trichophila FL Trinity

Elytroderrna deformans PP, JP Statewide

Maple scorch BM Trinity, Shasta, Siskiyou

Naemacyclus sp. MP Hnqf Ranoo

Phaeocryptopus gaumanni DF Humboldt

Rhabdocline pseudotsugae DF Mendocino

Rhytisna acerinuq Nevada

Scirrhia pini Mendocino

Qanfnni q cn uuHvv!ru ry. Trinity County

Stigmina thujina P0c DeI Nort.e

NURSERYDISEASES

Botrytis sp. DF, RF, Humboldt I GS Butte ! I A I Rtd Yo1o, Ilumboldt I ,! I Didymascellq (Keithia) thuj ina ll]Rc Hunboldt I

Dothistroma pini WWP,PP Hurnboldt

Fusarium sp. DF. PP Butte WF Humboldt, E1 Dorado, Butte RF El Dorado, Butte SP Butte, El Dorado, Santa Cruz

-25-

I TABLE V. (Cont. )

AGENT HOST COUNTY

NURSERYDISEASES

Melampsoridiuq alni WA Humboldt

Phoma sp. DF Humboldt SG, WF Santa Cruz

Phomopsis sp. DF Humboldt

Phytophthora sp. WF Santa Cruz

Powdery mildew BM Humboldt

Sonl nr--i q qn 4!+ vr. AL Humbold t

Sirococcus sp. JP Humboldt

Srrn scorch TP El Dorado

ROOT DISEASES

Armillaria sp. SP Lake DF, T0 Santa Cruz

Ileterobasi.dion annosum WF Sierra, Plumas ur Mendocir-ro PP Shasta GS Siskiyorr

Lcpt j ograph un1 qagener i PP Shasta, Menclor:ino, Siskiyou

DF Tninifv Hrrrnhnldf Mendocino

Phellinus weirii DF, WF llunboldt, Siskiyou llvr,o_plltgrs lateralis POC De1 Norte PY Del Nort,e

CANKER DISEASES

Rni nrznqnhqoni q v' r:rqvtr +u ribis GS Sonoma,Napa, Mendocino, Hurnboldt Chapparal Ri rror.ei do San Diego.

- zo- TABLE V. (Cont. )

HOST COUNTY

CANKERDISEASES

Cytospora abietis Flnqf rnnoa

Fusarium subglutinans MP Alameda, Monterey, Los Angeles, San Benito, San Diego, San Francisco, San Luis Obispo, Santa Barbara, Santa Cruz. PP Santa Cruz. CP Monterey.

Fusicoccum aesculi MA Humboldt., Sonoma, Mendociiro

Seridium cardinale RW, MC Mendoci.no

PARASITIC PLANTS

Arceut-hobium spp. WF Plumas, Siskiyou PP Lake BS Siskiyorr nr Host range DF Siskiyou

l)horadendron sp. WF San Bernardino

RUST DISEASES

Cronartium ribicola SP Lake

Melampsora medusae DF Plumas

Melampsorella caryophyllacearun RF Sierra

Peridermium harknessii MP Humbofdt KP Sonoma

Pucciniastrum epifobii WF Siskiyou

Pucciniastrum goeppertianum WF- Mendocino

a. Not a complete listing for all locations reported, nor for reports of comnon diseases,

-27 -

I HOST ABBRE:VIATIONS

AL = Alder BS = Brewer spruce BM = Bigleaf maple BP = Bishop pine CN = Conifer CP = Coulter pine DF = Douglas-flr FL = Oregon ash FV = Modesto ash GF = Grand fir GS = Giant sequoia Hli = Hardwoods IC = Incense-cedar JP = Jeffrey pine KP = Knobcone pine LP = Lodg;epo1e pine MA = Paclfic madrone MP = Monterey pine PC = Pear PM = Pinyon pine POC = Port-Orford-cedar PP = Ponderosa pine PY = Pacific yew DP = Digger pine RF = Red fir RW = Redwood SP = Sugar pine TF = True firs T0 = Tan oak WA = White alder WF = White fir WJ = l{estern juniper WRC= Western red cedar WWP= Western white pine

-28- r STATUSAND CONTROLOF ANIMATPESTS

A Report to t/l,e Corlfiollnfa, Forest pect Counsil lron tha Anhrto,l Dorruge Cunmittee

f"\ t ) 5'. fl :#) lr.r{.1

Gregory A. Cittrlti" Clwtr Robert S chtni.d,t S ecreta:ty

\tpy! Compilnd W: Jotm E. Botreeco Ed;ited,,by hegory l. e*wA Deeernber 28, | 990

-29- t STATUS AND CONTROLOF ANIMAL PESTS

INTRODUCTION

This report summarizes the Animal Danage Committee's survey of vertebrate damage of forest trees sent out as part of the California Forest Pest Council's annual overview of pest conditions in California. In August 1990,1!6 surve-v forms were nailed to federal, state, and privaLe foresters, forest companies and other agencies throughout California. A total of 48 (3O%) responded from JJ counties and are included in this analysis.

RESPONDENTSAND LOCATIONOF REPORTS

Surveys were returned by representatives of the U.S. Forest Service (n=18), California Department of Forestry and Fire Protection (n=12), private timber companies (n=B), and other organizations (n=10); these include the Bureau of Land Management (4), National Park Service (3), California Department of Parks and Recreation (1), University of California Cooperative Extension (1), and the Nature Conservancy (1) (Figure 4). Counties represented by the retur:ned reports cover approximately 3/4 of the land area of Cal-ifornia. These include: Butte, Colusa, DeI Norte, E1 Dorado, Fresno, Glenn, Humboldt, Inyo, Kern, Lake, Lassen, Los Angeles, Madera, Mariposa, Mendocino, Modoc, Monterey, San Bernadino, San Diego, Shasta, Sierra, Siskiyou, Tehama, Trinit-y, Tulare, and Ventura (Figure 5).

ORGANIZATIONSRESPONDING N=48 .'''"'. lll (10)20.83%

(8) 16.67%

EICDFFP[i]lusFs EPRTVATEmOTHER

Figures 4 & 5. 4, Organizations responding to the Animal Dalage Committee's survey of vertebrate damage of forest trees in 1990; 5, California counties represented by returned reports.

-30- SPECIES CAUSING DAMAGE

A variety of manmal species caused danage to forest trees, and the damage varies by area and agency. The najority of repondents reported danage fron deer, pocket gopher, porcupine, rabbit, and donestic stock. No damage was reported for birds, and other "mice" (which nay include shrews) (Table Vl,Figures 6 & 7).

Table VI. Number of Respondents Reporting Damage. (n = 48)

Species USFS CDFFP Pri-vate 0ther Total

Beaver 1 U o 1 z Birds 0 0 0 0 0 n Black Bear I 2 o 9

Deer t< 9 5 4 3r_ Dusky-footed Woodrat 0 2 z 0 4 tr1k 1_ 1 1 0 2

Meadow Mlce U 1 0 0 I Mt. Beaver l_ 3 0 o 4 Pocket Gopher 5 A l_ .l

Porcupine 6 5 z 1 14 Rabbi t 6 2 0 z 1n Tree Squi.rrels 0 2 0 0 2

Domestic Stock 1n 5 3 1 1_B Ground Squirrel 1 ,l 0 o 2 Feral Pigs 0 0 0 - 2

lr') Total Reports 53 'rJ 19 72 L26

SPECIESCAUSIT{G DAIIAGE ROOEr(TS 05'r0 1520

2 WOODRA 2 ul 2 pocrET

'ro 15 20 25 HO.OFDATIAGE REPORTS

Figrres 6 & 7. Species causing damage as reported in the Animal Darnage Comrnittee's survey of vertebrate damage of forest trees in 1990; 6, rodents; 7 szma an i m=-l q It

-31 -

I SCOPEOF DAMAGE

Damage from aII sources was reported on land in excess of 755,000 acres. Al1 of California's najor timber producing regions and tirnber types have reported damage caused by vertebrate species. In several cases respondents indicated that injury fron vertebrates occurred, but not at, levels sufficient to justify the amounL of time and effort to quantify the data.

In nany cases respondents reported danage from nultiple species of vertebrates that requires highly variable approaches to ninimize danage. Figures 8 and 9 demonstrate the scope of the danage being caused. Species are divided into game animals and non-game groups (rodents) in order to easily distinguish the control and managemenLoptions available to the practicing forest manager.

ACRESOF REPORTEDDAMAGE RODENTS

4,000

MT.BEA

POCKETGOPHER

PORCUPINE 9,700

GR.SOUIRRE

GAMEANIMALS

BABBITS&

TREESOUIR

FERALI

ACRES

Figures B & 9. Acres of damage reported to the Aninal- Darnage Committee's survey of vertebrate damage of forest trees in 1990; 8, rodents; t, gane animals.

-?)- ANIMAL DAMAGE TRENDS BY FOREST TYPE

'largest, Redwood - Douglas-fir Type. Vertebrate species represent the single pest problefi in ttre redwood/Douglas-fir forest type. In terms of geographic focations this type is restricted to the northern coastal counties of Calif'ornia. The counties of De1 Norte, Humboldt, and Mendocino have all reported stable to increasing problens with bl-ack bear, black-tailed deer, dusky-footed woodrat, elk, mountain beaver, and tree squirrels.

The primary species of concern, black bear, deer, eIk, and tree squirrels, are all classified as game animals by the California Department of Fish and Game. Because of game status, management options are highly restricted and must often be implemented during times ofl regularly scheduled hunting seasons, precluding Lire need to tine control or management options Lo tines when Lhese may be nost, effective.

The dusky-footed woodrat often can cause severe darnage in localized areas. As with most rodents, the damage is characterized by gnawing of the bark and feedir-rg on the cambial layer. Private timber companies reported a totaf of 4,000 acres impacted by this species in I99O. In light of newly enacted legulations regarding the spotted ohrl, control options for woodrats are ttncerLain at this time. The woodrat is considered a preferred food species for Lhe ow1. This designation will certainly affect future control strategies.

True Fir Forest Type. Respondents to this years survey were of the opinion tl'at.-ryatepeStSwaSgenera1lyontheincrease.Speciesof gleatcst concern were deer, pocket gopher, porcupine, rabbits and hares, and dornestic stock. In many cases respondents reported damage on more than a si rre'le l.l-ee snecies.

Species such as deer, pocket gophers and lagomorphs (rabbits and hares) intpacted trees generally less than 10 year old. In many cases management options flor protection of above ground tree parts favored the use ofl some type of exclusionary device, e.g. netting, shel-ters, and tubes. In selected cases forest personnel have relied on repellents to provide some level of control.

Pine F-orest Type. This forest type suffered high levels of damage frorn toth pocket gopfter and porcupine. Recurring drought conditions throughout California appear to have benefitted both species by allowing populations to remain at relatively high numbers throughout the winter nonths. These species by fal represent, the greatest threat to plantations and natural stands of trees. In some areas plantations were replanted for three consecutive years because of repeated danrage caused by pocket gophers. Damage from pocket gophers and porcupine were reported from the counties of: Butte, Colusa, El Dorado, Fresno, Glenn, Humboldt, Inyo, Kern, Lake, Lassen, Los Angeles, Madera, Mariposa, Mendocino, Modoc, Nevada,0range, Placer, Plumas, Riverside, San Bernadino, San Diego, Shasta, Sierra, Siskiyou, Tehama, Trinity, and Tulare.

The other major vertebrate pest of this forest type is domestj-c livestock. This is a recurring problem and is often one of the most difficult to manage. Ilistorj-caI grazing patterns, large acreage allotments, and relatively light stocking densities all conpound the problen. The most effective nanagement option is total exclusion through fencing; I3/, of those reporting livestock damage have used this approach. More forest nanagers are trying to implement forest grazing management strategies that mininize darnage. This will probably increase due to the increasing costs associated with fence construction and

-33-

I maintenance. Counties reporting danage from donestic stock ltere: Fresno, Inyo, Lassen, Madera, Mariposa, Modoc, Nevada,Orange, P1acer, San Diego, Shasta, Sierra, Siskiyou, Tehama, Trinity, and Ventura.

Hardwood - Conifer Type. Reports of damage to oak (Quercus sp. ) by feral pigs a domestic stock were given again in 1990. The inpact was reported to be on regeneration efforts. This is only the second year that feral pigs have been reported in the survey. fn 1989 danage reports were given from only two counties. In 1990 the nunber of counties reporting danage increased to five Kern, Monterey, Sacrsmento, San Benito, and Tehama. In all cases control was reported to be exclusionary fencing. In some cases nanagers are using direct nethods of population reduction in conjunction with fencing to minimize danage.

i; I I :

-34- STATUSAND CONTROLOF WEEDS

A Report to tlw Caltlotndn Fweet Peet Counctl frorn ilw Veed, Corrvnittee

Nelson trlonny, Chetr Glenn Luttok, Se ereto,ry

Edited W Clenn LLLna* Decentber 14, 1990

-3 5-

I STATUS AND CONTROL OF WEEDS

California continues to have a diverse problem with weed competition that affects the survival and growt-h of forest plantal-ions in all forest types. Plant species creating cornpetition are many and f requently include otl-rer conifers. The followjng fist includes some of the nost common:

annual grasses lupine bear clover madrone bigleaf maple nanzanita, nonsproutlng bitterbrush manzanita, sprouting bitter cherry mountain whitethorn black oak oceanspray gnnsses nor.cnn! vrrr ial bracken fern F! broadleafl her:bs rabbitbr:ush canyon live oak lllgr rpp. chinkapin sagebruslt conifers snowbrush deerbrush tanoak.

Insects infesting regenelation such as the gouty pitch midge, Lhe pine needle sheathnriner, and pine reproduction weevil find favorable hosts in pines under severe competition stress. Relief from the stress lrsuallv a11eviates the insect problem.

The recent comblnation of drought and fire l'ras created a serious problem wilh weed competition. Private Land managefs conlinue to use a spectrum of available herbicides to ensure successful regerreratiolt; meanwhiie the U.S. Forest Service has completed a seventh glowing seasor) without herbicides. Thus, a dramatic contrast can be seen in Tuolunne County where, after the l-9B7 Stanislaus Fire, private forest lands have been almost completely reforested while the Forest Service has had serious problerns in establishing plantations. Resunption of the use of herbicides on the l.iational F'orests depends on resolution ofl the 22 appeals to the Vegetation ManagemenL Environnental Impact Statement. As of November 9, 2I of Lhe 22 appeals have been processed by the Office of General Counsel in Washington, D. C.

The following herbicides \,rere available for use in California forests duling 1,990: atrizine, glyphosabe, hexazinonc, triclopyr, and 2,\-D. Astrlarn, dichlorprop (2,4-DB) , and picloram are no long;er availab-le for forest use. KNOTYYOUR FORESTPESTS

CALIFORNIA FI.,A,THEADEDBORER

The California flatheaded borer, Melanophila drunnondii, is prinarily a pest of weakened or stressed Jeffrey or ponderosa pines in most of California. More often than not, it is found:'-n trees along with one or more bark beetle species the western pine beetfe in ponderosa pine, the Jeffrey pine beetle in vurrrvJraffnorr yrrrLtnino ond pine engravers and the red turpentine beetfe in bOth hOStS. Other tree species attacked are sugar, Coulter, Monterey, digger and knobcone pines.

In Southern California this insect is more aggressive and frequently kills pines in the absence of its fellow insecl- pests, and even without the frequently concomitent annosus root disease. Usually larger trees are atLacked, but trees as smal1 as saplings roay be attacked. Attacks may occur over the entire tree, part of a tree, €.8. the top or mid-bole, or a strip on one side ca1led a strip attack. Attacks on boles are usual, but tops and limbs may also be successfully colonized. Borers may continue their developrnent in boles, tops and limbs when trees die or are felled and utilized.

Evidence of Attacks. When a tree dies from flathead attacks, croh,n fading is indistinguishable from the fading due to attacks by bark beetles. This seems only logical as both flatheads and bark beetles may be in the tree at any one tine. Like bark beetles, the adults may have energed before the foliage is noticeably changed in cofor. However, unlike bark beetles, the exit hole will be oval and sma]1. noL round and small.

Galleries of larger larvae wind through the inner-bark. Galleries are 3/B to 5/8" wide (10-1"5 mm) and solidly packed with frass and borings, which are deposited in a clearly defined, crescent pattern (Fig. 10). Attacks may produce thin resin streams down the bole if the tree has some ability to resist. Trees under great stress do not produce streqrns for resin. Pitch tubes produced from attacks by bark beetles do not occur with attacks by the California flathead borer. Neither wiII you find boring dust caught in bark fissues as may occur wj-th some bark beetles.

Life Stages. The adult beetle is a small elliptical, flat beetle somewhat boat-shaped when viewed from above, or a bit like a patch in plywood. It is black or near black above and nay bear 1 to 3 ye11ow spots on each wing cover. However, many adults have no spots. The under side is a dark brassy green. Eggs are about l- mn in size and difficult to locate.

Young larvae match the sapwood in color. The area behind the head is enlarged laterally, which gives larvae the characteristic of being shaped like a horseshoe nail (Fig. 10). In the last instar, prepupal stage, the larvae shortens, thickens, and the body is bent double within the pupal chamber. The pupa is a stage wherein the final transforrnation to an adult occurs. lrlings, antennae, eyes, and other externaL body parts are visible at this stage.

Life Cyc1e. Adults emerge May to August. In Southern California one would assume early rather than later, but portions of the population may not be synchronized. Local weather;,ry be influencial in timing from year to year.

-37- I

When adults emerge they feed on foliage, which is necessary for the female to develop viable eggs. Damageto the foliage is seldom noticeable.

Eggs are placed under bark scales bordering on crevices. Hatch occurs in 1 to ] weeks. The first instar larva mines directly into the cambium, turns horizontally, and nines at the phloem-xy1em interface. These tiny mines heal if the larva dies or becomes an "incipient" larva. The result. is a warty ridge on the xylem that will become encased if the tree continues to live.

Normally the life cycle completes within one year. However, larvae that become 'rincipientr may survive up to 4 years in this relatively inactive state. Mortality rates of these larvae are high and trees can be found that have survived numerous attacks indicated by the abundance of "warty" ridges.

However, should the host lose vigor for any reason, the incipient larvae are somehow stimulated to initiate normal growth and complete their life cyc1e. The result is a dead tree or a strip of dead bole. Thus, stress placed on a tree up to 4 years after the initial attacks may tri.gger tree death from an earlier flathead population residing under the bar:k in the incipient stage.

Year X x+l X+2 X*3 X*4

Drought, nornal Damage to Incipient or l-atent larvae flathead moisture roots or complete life cycle, killing attack return of tree. drought

Figure 10. Larva and galleries of the California flatheaded borer.

-JO- Index of Previous Topics Utilized in KNOI.IYOUR FOREST PESTS.

YEAR TOPIC PAGE NO.

1qqo CALIFORNIA FLATHEADEDBORER 37 r qRq None written 1_gBB BLACK BEAR DAMAGE 3o 1aq'l THE COUTYPITCH MIDGE 20 1986 THE EUCALYPTUSBORER 22 1 oRq BRANCHAND TWIG DIEBACK OF OAKS L9 1984 GYPSYMOTH 20 1qB? TANOAK L9 t qAz WOODRATS 17 1gB1 DUTCHELM DISEASE 18 lgBo PHYTOPHTHORAROOT ROT OF PORT-ORFORDCEDAR I6 1q7q TRUE MISTLETOEON WHITE FIR 16 't olR MYCORRHIZAE 2T t977 FOMESANNOSUS IN RED AND WHITE FIR 72 1o'7 6 NURSERYDISEASES 1-L CYTOSPORACANKER OF TRUE FIRS 13 rY t1 SALT DAMAGETO ROADSIDECONIFERS 13 r973 BLACKSTAIN ROOTDISEASE 13 1Q'7) PHLOEMNECROSIS OF DOUGLASFIR 14 1971 ELYTRODERMANEEDLE DISEASE OF PINES 13 r97o FOMESANNOSUS ROOT ROT 79

The State Conditions report is available at the following libraries:

LIBRARY/CITY YEARS

California State Library, Govt. Publications Section, 1946 to present Sacramento

University of California - Berkeley 1946 to present University of California - Los Angeles 1955 Lo present University of California - Santa Barbara L956 Lo present University of California - Riverside Sporatic years University of Oalifornia - Davis Sporatic years University of California - San Diego Sporatic years

Stanford University, Palo Alto Unknown

USDA Forest Service, Pacific Southwest Range and Experiment Station - Berkeley 1946 to present

-39- SURVEYSAND EVALUATIONS

DEMONSTRATIONTHINNING PLOTS IN THE EASTSIDE PINE TYPE ON THE IASSEN NATIONAL FOREST. In 1978-1979 the Forest Service established plots in the eastside pine type to show the effects of thinning on pest-caused losses in areas of high tree mortality. The stands chosen were mostly pole-size ponderosa pine mixed with sone white fir and incense-cedar, growing on medium to low sites, and nanor'no in ad6 qb" from 7A to 90 years. Within the demonstration plots, four levels of stocking density -- 40, 55, 70, and 1OO percent of normal basal- area were established to demonstrate the biological and economic alternatives available for managementplanning. (Norual basal area is the basal area that a stand should have reached when fully stocked with trees, which in the demonst.ration areas, ranges fron 185 to 2r5 sq ft/ac, depending on site quality. ) Ten years after thinning, the treatments had reduced mortality frorn !O to 100 percent of the l-eve1 in unthinned stands (Table VII).

TABLE VII. COMIIMRCIAL TREE MORTALITY BY STOCKING LEVEL, TEN YEARS AFTER THINNINGA

Residual Stocking After Thinningb Year 40% 55% 70% LOO'/" Trees per Acre qBo 1 0.0 v.1 o.2 2.4 1gB1 0.0 0.0 o.7 2.4 1qB2 0.0 u.) 0.3 J.o 1983 0.0 0.1 0.8 4.r 1984 0.0 0.0 0.0 1.0 1985 0.0 o.2 0.0 0.6

rgB6 0.0 0.0 0.0 r.J qR" 1 0.0 0.0 0.0 14 lgBB 0.0 0.0 0.0 0.0

10Ro 0.0 0.4 0.0 z.o 1AOn 0.0 0.0 0.0 2.6

Mean 0.0 0.1 o.2 2.O

Percent Mortality Reduction Compared with Norrnal Basal Area 100 95.0 90.0 acommercial trees are B inches dbh and larger, with straight bores, yielding at least one 1O-foot 1og with a 6-inch top. Trees were killed r_ by the mountain pine beetle. "Percent of norrnal basal area.

-40-

I DROUGHTMORTALITY IN THE NATIONAL FORESTS OF CALIFORNIA.

TABLE VIII. ESTIMATEDMORTALITY AND SALVAGEON NATIONAL FORESTSIN CALIFORNIA TO JUNE 30, L99O*

National- Est. Total L0 Yr Ave. Salvage Salvage Sales, Vol. Estimate Forest. Merchantabl-e Softwood Tnnqof MMBF Dead Timber Sell, 79-89 trY-qo Salvage Est. Offer (5) MMBF (1) MMBF(2) MMBF(3) Offer (4) for FY90 to6

Angeles (*) ll (*) (*) Cleveland (*) .0 (*) (*)

Eldorado 1000 r29.9 145.o L)+..+) 250 Inyo o.2 7.3 0 0 0

Klamath 59 176.8 1.06.7 54.89 37.5 Lassen 150 158.4 35.o 18.47 40.0

1 Los Padres (") .I (*) (*) X{endocino 1- 79.2 30.o 0.986 10.0

I{odoc 45 53.0 4.0 0 0 Plumas 300 178.6 10.0 38.29 r20

San Bernardino 60.0 0 1".5 Scquoia 5O 77.4 3.0 1.18 I5 q Shasta-Trinity BO 2nn l.u 37.73 40 Sierra 150 118.9 57.o 5o

Six Rivers 16.6 23.O 10 Stanislaus 500 704.2 60.0 62.O3 1 2tr,

Tahoe 250 1)1 0 81.o 19.13 100 LTBMU 50 '7 18.0 2.BB 20

Totals zoll 151.4.6 640.2 4r7.98 810 uTirb." Management Staff, Pacific SW Region, San Francisco, CA 94111. (1) Total estimated mortality from CAS (Capable, Available, & Suitable) land due to the current drought (est. 6/29/90), (2) Ten year average seff from CY-1,979 through CY-1989 of softwoods (Source: cut and sold reports). (3) Management attainment target 17.2 (Salvage Timber Offered, 1tJ0 Feb. 1990). (4) New salvage sales offered from PSTAR (Periodic Timber Accomplishment Report - STAR-based), 6/30/90. (5) Salvage volume that could be offered or added to existing sales in FYIO. (*) Salvage volune included with San Bernadino NF estimates.

-41- NEI,rlDWARF MISTLETOES IN CALIFORNIA. Three new species and one new subspecies of dwarf rnistletoe have been confirned for California by Frank Hawksworth, Rocky Mountain Forest and Range Experimer:,t Station, and De1 Wiens, University of Utah. Two of the new species, Arceuthobium siskiyouense and A. monticola, occur in the Siskiyou-KIamath Mount.ain floristic province of northwestern Cal-ifornia and Southwestern Oregon, an area well known for its high degree of plant endemism. The third species is A. l-ittorum, and the subspecies is A. tsugense subsp. mertensianae.

Arceuthobium siskiyouense, a parasite of knobcone pine, was segregated from A. campylopodum, a widespread species that commonly occurs on ponderosa, Jeffrey, and other pines. 4. monticola, a parasite of western white pine, was separated lrom A. californicum, which is now considered to be a California endemic esse.tiiafly restricted to sugar pine. Arceuthobium littorum parasitizes Monterey and bishop pines in coastal California. It was formerly included under A. occidentale, which is now considered to be an interior species prirnarily pa"asitic on digger pine. The new subspecies, 4. tsugense subsp. mertensianae, which infests only mountain hemlock, is distributed from southern British Columbia to the centraf Sierra Nevada Mountains in California. The coastal, typical phase found only on western hemlock, which is rare in northwest California, thus becomes A. tsugense subsp. tsugense.

ANNOSUS ROOT DISEASE CONTROL. Mechanical harvesting with various types of shearing equipment is increasing in areas of eastside pine. This forest type is known to have high levefs of annosus root disease introduced into stands through pine stumps. Most timber sales in these areas use borax on stump surfaces to prevent infection by the causal fungus, Heterobasidion annosum. The granular borax registered for this use has limited solubiliLy, and there is irrterest in finding a soluble material that might be applied by the equipment during shearing. This could reduce labor costs. Also, some of the shearing equipnrent causes uneven stump surfaces and flracturing of the stllmps that cannot be effectively treated with granular borax. A material has been tested in the southeastern United States for this purpose andrgimilar tests were performed in California. The material is known as TIM-BOR-" and is produced by US Borax for use as a wood preservative for the treatment of lumber.

Tleattnents were performed in two areas: (1) a tinber sale on tl-re McCloud Ranger District, Shasta-Trinity National Forests, with the use of a Temco Roto-saw, and (2) on the Devils Garden Ranger District, Modoc National Forest, with the use of a Hydro-Ax 7LI shearhead. Both naturally and artificially inoculated stutnps were treated. The following 1evels of stump infection occurred B weeks after treatment.

McCloud Devifs Garden Treatment: Chainsaw, Control Uninoculated r) /o )vh Chainsaw, Control Inoculated 1J 95 1 Chainsaw, Borax Inoculated I 95 Shearer, TIM-BOR fnoculated 0 60 Shearer, TIM-BOR Uninoculated 0 10 TM TIM-BOR-" appears to be at least as effective as standard borax application in these trials. Levels of infection were hieh in the Devils Garden trial

-42-

I because of the high level of inoculum used. Conversely, the McCloud inocula{fions did noL appear to be effective. fn both cases however, the TIM-BOR^" treatment did reduce the amount of infection.

DUTCH ELM DISEASE. The California Department of Forestry and Fire Protection confirmed 2lt diseased elms in 1990. 0vera11, the number of diseased trees was cornparable to disease activity in previous years (Table IX).

Dutch e1m disease (DED) has expanded into the Central Valley of California. Ten t,rees were confirmed from Sacramento County, and a quarantine has been establ-ished in portions of San Joaquin, Sacramento, and Yolo Counties.

The incidence of DED in Santa Clara and Alarneda counties increased dramatically from past years. The city of San Jose had 47 ofl Santa Clara County's 5I DED elms with most of the confirmations coming from several concentrated areas. In Al-ameda County, DED was widespread with confirmations in Piedmont, Oakland, and Berkeley. Alameda County is the only Bay Area county without a DED interior quarantine.

Marin County continued to show a reduction in diseased trees compared to previous years. Disease incidence was stable or increased slightly in Contra Costa, Napa, San Mateo and Sonona Count,ies.

TABLE IX. NUMBER OF CONFIRI'{ED TREES I,IIITH DUTCH ELM DISEASE

COUNTY 1969 100n Afameda 0 11 7 3 23 Contra Costa 21, 30 35 35 34 3B Marin I54 83 o1 BZ 46 q Il Napa 2 3 2 ,) a Sacramento O o 0 0 0 10 San Francisco 0 0 0 0 n 0 Iro '7n San Mateo 63 44 1l 4B 61, Santa Clara 34 41 20 35 ?2 5r Solano 0 1 0 0 0 Sonoma 28 14 I6 ),2 3 6 Total z 21,O 25

a-Through December 11, I99O

TREE DIAGNOSES, CDF&A. The California Departnent of Food and Agriculture is frequently requested to identify the cause of injury or disease on various species of trees. The latest listing is gi-ven in Table IX.

-43- Table x. CALTFORNTADEPARTITIENT oF FooD AND AcRrcuLTURE, TREE DrAcNosES Lo/89 THRoucH LL/L3/9o

HOSTTREE DIAGNOSIS

Abies concolor ( seedlings ) Fusarium oxysporum Butte

Abies concol-or (Christrnas trees) Pucciniastrum goeppertianum Humboldt Twr'lte-FirI- ( fir-huckelberry rust)

Abies magnifica ( Seedlings ) Fusariun oxysporum Butte

Abies magnifica (Christmas trees) Armillaria mel1ea Nevada (red fir)

Acer sp. Xy1el1a fastidiosa Glenn (bacterial scortch)

Acer macrophyllum Rhytisma acerinun

Acer palmatun (Japanese maple) Phenoxy herbicide injury Sacramento

Acer palmatum (Japanese maple) Verticillium wilt Sacramento, (Y. dahliael Humboldt, Santa Barbara, Placer

palmatum Acer var. "Bloodgood" Verticillium wilt Santa Clara (Japanese maple) (Y. dahliae)

A1nus sp. Cyl-indrosporium sp. Mendocino ( leafspot )

Alnus sp. Septoria alnifolia Mendocino ( leafspot )

Afnus sp. (firewood) Trametes versicolor (conk) State of Oregon ( alder)

Arctostaphylos sp. Fusicoccum aesculi (canker) San Diego (Manzanita)

Calocedrus decurrens- (seedlings) Fusarium oxysporun, root and Butte Tlncense-c"da") hypocotyl rot

Casuarj-na glauca Genetic fasciation Fresno ( beefwood )

Chamaecyparis pisifera Pestalotiopsis funerea Santa Barbara (Sawara cypress) (twig blighr)

Chamaecyparis lawsonia,na Stignina thujina Humboldt (Port-0rford-cedar )

-44-

I Table X (Cont. )

HOST TREE DIAGNOSIS COUNTY

Cocos pl-umosa (nursery) Gliocladium vermoseni Santa Barbara Tprnk bud rot)

Cupressus macrocarpa Pestalotiopsis funerea San Francisco (canker)

Cupressus sempervirens Botyosphaeria ribis (canker) Sonoma

Eucalyptus sp. Lignotubers (normal) Stanislaus

Eucalyptus camaldulensis Salt damage Fresno

Eucalyptus globulus Hydnangium carneum, false Glenn (blue gum) truffle, mycorrhizal

Eucalyptus globulus Hymenogaster albus, Glenn (blue gum) mycorrhizal

Eucalyptus gl-obulus Setchelliogaster tenuipes, Glenn (blue gurn) false truffle, mycorrhizal

Eucalyptus lehmanii Glyphosate injury & oedema Santa Barbara

Eucalyptus rudis Oedema Santa Barbara

Eucalyptus sideroxylon Oedena Sacramento (Red ironbark)

Fraxinus sp. Cercosporella trichophila Trinity ( ash) (leaf spot)

Fraxinus sp. Pleurotus ostreatus Sacramento (ash) T"ood rot)-

Fraxinus uhdei Pleurotus ostreatus & Sacramento =--=-- Polyporus sp. (wood rot)

Heteromel-es arbutifolia Fusicoccun aescufi (canker) Orange

Liquidambar styraciflua Glyphosate injury Sacramento ( sweetgum)

Magnolia soulangiana Oedena Santa Cruz

Myrica californica Ranularia destructiva Humboldt (a wax myrtle) Tleaf spot\

Osmanthus fragrans 0edema Santa Cruz

Persea americana Ganoderma lucidum Shasta

-+)-lt- Table X (Cont. )

HOST TREE DIAGNOSIS COUNTY

Pinus lanbertiana (seedlings) Fusariun oxysporun Butte

Pinus monophylla Sphaeropsis sapinea Santa Barbara (singleleaf pinyon) (=Diplodia pinea)

Pinus ponderosa (seedlings) Phona eupyrena Anador (ponderosa pine)

Pinus radiata Fusariun lateritium Alameda (l,tonterey pine)

Pinus radiata (Sall, western Fusariun subglutinans Santa Cruz gall rust) (pitch canker)

Pistacia chinensis Verticillium dahliae Sacramento TChfnese pistactriol TVe;tr;IEnm '^rir.t)

Platanus sp. Discula unbrinella San Mateo ( "Colunbia sycamore" ) (antnracnosel--

Platanus ori.entali-s Microsphaera penicillata Sacramento torienr"arEanil (powdery nildew)

Populus sp. Cytospora chrysosperma Siskiyou (poplar) mechanical wounding, borers

Populus trenuloides Marssonina castagnei Siskiyou ( aspen) TGaf spot)-

Prunus domestica Pseudomonas syringae pv. Yolo (coonrnonga.ae.t pfur) syringae (bacterial canker)

Prunus hyedoensis Armillaria mellea Sacramento

Prunus hyedoensis Plun line pattern virus Placer var. akebono

Prunus persica Sphaerotheca pannosa Yolo (peach) (powdery mildew)

Prunus persica Tranzschelia discolor San Luis Obispo (peach) GGT]-

Prunus persica var. Sphaerotheca pannosa Yolo nucipersica (powdery mildew)

Prunus virginiana Apiosporina norbosa Tulare (choke cherry) (=Dibotryon norbosun, "black knot" )

Pseudotsuga menziesii Phellinus pini Siskiyou

-46-

I Tab1e X (Cont. )

HOST TREE DIAGNOSIS COUNTY

Pyrus comnunis Erwinia amylovora Placer (common pear) (fire blight)

Pyrus kawakamii Armillaria mellea Sacramento

Pynrs kawakamii Entomosporium mespili San Francisco (leaf spot) Sacramento

Quercus agrifolia Sphaerotheca lanestris San Luis Obispo (coast live oak) (powdery nildew)

Quercus kellogii Septoria dryina (1eaf spot) Trinity (California black oak)

Quercus ]obata Diplodia quercina Sacramento

Quercus lobata (seedlings) Macrophomina phaseolina Sacramento (valley oak) (charcoal rot)

Quercus wislizenii Cryptocline cinerescens Butte (irtte"ior f itre oat ) (twig dieback)

Salix sp. Melampsora epit,ea San Mateo

Sequoiadendron glgenqge Botryosphaeria ribis Napa (giant sequoia) (canker)

Sequo i aden dron g1-sqleq Botrytis cineria Yolo (giant sequoia) (seedling blight)

Sequoi adenend ron gigelltelm Macrophomina phaesolina Butte ( seedling)

Ul"mus pumi la Phoenix herbicide injury Sacramento (Siberian eIm)

!e!h'_!e!s!re _!94€!q Epleereqeqlsneowashint- Santa Barbara tonj-ae ( leaf spot )

-+ l- - inltlD r?atE3 otpatlrrrt 07 lcelcul.fltt.B FoR!lIl 3rnvrcu crlltEstlr 'ar!{. pE:t|-a;; FOR.EST PEST DETECTIOI\T R.EPOFTT--'-'

I. nED IXIUIAflU (Seeirctnrtiom onreverse)

l. c0ulrTt: 2. toRISl(FS CIitr): 3. DrSrRrCl(rS0t{rl):

{. LXGATDTSRIPIIO}I: 6. [fflTl0r: 7. ttilNNfltHSSlP: ?._R._ rorustsmncB section(s) _ mmPmnn sltTg 5. DITB: PRIUN

8. S0SPECTTDCrUSE(S) 0f nnm: 9. SrW(S)0rnm rfPECr0: t0. Prm(sl0F lTtt lfFDCtB: f. ilstcT 5. ffruCll 1.stmr,nc E {. smTuBnE 1. RMT 5.mc F 2. oISEISI 6. IECIAI{IC& 5'ovnrAT{'RE Lr 2. BRITCH 5.rourcE 3. NITIT H H 7. tEtD l: Hrlt*' 3. LnDn 7.BUD H {. TEATIER 8. Iilnml {. B0tE g.c0{r | |

1I. SPECIHIffif,TID: 12.IUMN AI?ECIE: t]. t&$ tffECIID:

I{. IilJINYDISTRIBIITIOT: 15.sutlls 0t ixJI]RY: 16.H.tvMIO[: L sctTTmxDf] 2.cRoupm ! r. DrcRxrsn{cn 2.sTATrc X 3.r}rcRxAsnc n

17. PH}ITATIO}I? 18. STA}IDCOI{POSITIO}I {SPECIISI : 19.STAilD TGE IID SIIBCIISS: - 1.rBs H 20. sTluIDDEISITY (BASII ARXA): 2r. SITE0UAtiTY: 2. ll0 LJ

22. PIST$lcs (Ip fffiit{) Al{0RixARxs (syl0T0{s ilCI c0lft?t80TlliG flcr0RS):

lz:.smn 2{.lml0{ RilulsrlD: 25.RIP0RTR'S ll?ilCI: 25.RXFORIER'S AGECI: roRxARnm? I l. liForu{Anoiloril E |"oF 2. ru rDE{TiFrClTrol{H 27. RMORIIR'SADDRXSS T PflOI{E I{UltBil: i 2.)i0 r I 3. PIzu[VAu]Anoil I I

u. nprr{Prn rurcnffi wB) 28.RB[utSE:

29. RtPoRlilUBIR: 30. DATEI ]i. NOTINN'SSIGIIATI]RI:

*48- Rs-3100-l{nrv. 3/90)

I TnECSPEP_ATIVI IORIST PEST DtTECIIol{ sURVEY is spnsored by t}re california Forest Pest council. Thecouncil encourages federal, state, andprivate land uanagers ard individualsto contributeto the Surveyby subnittinqpest injury reportsand salples in thefoilouinq Danner.

pEDmLpERSo[fn. Send aII detectionreprts throughchannels. ltail injury salplesnit]r a copyof this rePortto oneof tbe followingaPProPriate offices:

USDAForest Service ForestPest llanagelent ForestPest llanagelent State andPrivate ForestrY Shasta-Trinityllational forests Stanislausltational Porest 630SansoDe Street 2{00flashington lvenue 19777Greenley Road SanFrancisco, CI 9{l1I Redding,Cl 95001 Sonora,Cl 95370

STATSpzksoillm. Sendall deteqtionreports tbrough cbamels. I{ail injury sauplesuittr a copyof tXis reprt to oneof tie f ollouingappropriate off ices:

California Dept.of forestry CaliforniaDept. of Porestry CaliforniaDept. of Forestry andFire Protection andPire hotection andFire Protection P.0. Box1590 5105tirprt Road 776S. StateStreet, 1107 Davis,Cl 95517 Redding,CA 96002 Ukiah,Ct 95{82-5891

PRIVATEL,MD I{AIIAGERS N{DIilDIqD0US. Send all detectionreports and sanples to tbe closestCalifornia Departrent of Forestry andPire Protection office listed above.

coxPl,EliltcTf,l DnBolotf RlFonTI0Rll

[L\DIilc(BInCKs l-7). EnteraII infornationrequested. In Block5, L0CAlI0il,provide sufficient infonation for tie injury centerto berelocated. if pssible, attacha locationmp to this forl.

IIJURYDESCRIPTI0X {BIrClG S-15). Checkas mnyboxes as are applicable, and fill in t}e reguestedinfonation as coupletely as possible.

STilIDDESCRiPTIOI{ (BItrKS 15-21). Thisinfonation uill aid the exarinerin deterniningbow the standconditions contributed to the pestsituation. In Block18, indicatethe mjor tree speciesin the overstoryand understory. In Block19, indicate the standage in years,and/or tbe size class (seedling-sapling;pole; youngsarrtinber; mture sartider; ovenature,or decadent).

PESTXfms (BI0CK22). I{rite a detaileddescription of the pestor pests,the injury syuptons,and any contributing factors. fCTIOxRE0UBSTID (BL0CK 2{). l{arkiField Rvaluation'onlyif youconsider the injury seriousenough to rarranta professional evaluation.llark ilnfonation Onlytr if youare reporting a conditionttrat does not requirefurther attention. All reprts riII be acisror,rledgedard guestions ansuered on t"belouer part of t"hisforn.

RIPLY{SKTI0tf II). llakeno entriesin this block;for eraliningpersonnel only. I copyof ttris reprt riII be returnedto youuith the infornationrequested.

IAI{DLIIGSII{PLIS. Please sublit injury sarplesritJt eachdetection report. If possible,send several spcirens illrstrating tbe stagesof injury anddecline. Keepsarples cool ald ship theuiuuediately after collection. Sendtner in a strudy container,and enclose a conpletedcopy of tbe detectionreprt.

Y00RPAXTICIPITIOI{ Il{ TIE CO0PERITM FORIST PEST DETECTI0I{ SffiVH IS GREATIYIEDED ll{D IPPRICIATID.ldditional copiesof this forn are avaiiablefron the PorestService, torest Pest llanageuent, ard fror tie CaliforniaDeputrent of Forestryand Fire hotection.

-49- @UNCIL AI{D CO{IIIiITTEEOFFICERS, 1990.1991

Councll ChaLr: Lloyd Bradshaw (Sinpson Timber Co., Klanath)

CouncLl Vl.ce-ChaLr: Dave Burns (RPF, Auburn)

CouncLl Secretary: Gregg DeNitto (USDA-Forest Servlce, Redding)

STANDING COITIIIITTEES

Insect CosmLttee: Chair: Don Owen (CA Dept. of Forestry & Fire Protection, Redding)

Secretary: John DaIe (USDA-Forest Service, San Francisco)

DLsease Coml.ttee: Chair: Mell-ssa Marosy (USDA-Forest Servlce, San Francisco)

Secretary: Tim Tidwell (CA Dept. of Food & Agriculturer Sacranento)

AnLnal Damage ComLttee: Chair: Greg Giusti (UC Cooperative Extenston, Lakeport)

Secretary: Robin Breckenridge (CA Dept. Food & Agriculture, Sacranento)

Weed ComLttee: Chair: Nelson Money (PG&E, Crass Valley)

Secretary: Glenn Lunak (Diamond Lands, Sterling City)

Southern CalLfornia Pest Comlttee : Chair: Dave Neff (CA Dept. of Forestry & Fire Protection, Riverside)

Secretary: Paul Rippens (L.A. County Fire Departnent, Los Angeles)

Edltortal ComrLttee: Chair: Don Perkins (CA Dept. of For. & Fire Protection, Sacra.mento)

Editor-in-Chtef: John Dale (USDA-Forest Servlce, San Francisco)

EXECUTIVE C'IIIIII TTEE

The Executive Comnittee is composed of the Council Chalr, Vice-Chair, Council Secretary, the Standing Connit,tee Chairs (5), and 3 nenbers-at-1arge:

Herb Baldwin (Roseburg Resources Co., Anderson)

Scott Johnson (Witbur-Ellis Co., Stockton)

Robert Schnidt (U0-Berkeley, Hopland Fie1d Station, Hopland)

-50-

I CALIFORTIA DEPARTMBNT OF FORESTRY AND FIRE PROTECTION 1{16 NTNTH STREET P. O. BOX 9{42{6 sAcR-AtfElfTo, cA 942rt-2460

TO: