Sarah Pickel - PA IPM Program PA Department of Agriculture

 Diseases Diplodia Tip Blight Rhabdocline Needle Cast Swiss Needle Cast Leader Death  Insects Bagworm Cooley Spruce Gall Adelgid Cryptomeria Scale Douglas-fir Needle Midge Elongate Hemlock Scale Fir Coneworm Mites – Eriophyid (Rust) and Spruce Spider Mites White Pine Weevil

 Managing a problem is much easier when that problem is just beginning.  The farther along a problem becomes, the more extreme the solution may be.  Does your farm have someone designated to conduct pest monitoring?

 Fungus affecting only Douglas-fir  Yellow defined spotting on current year’s growth first visible in October.  Generally starts on lower branches of tree.

March 7

May 6

End of June

Detection - Look in areas that remain wet:  Low lying areas  Shady areas  Along tree lines with more mature trees  Northern exposures  Around ponds  Areas with poor weed control  Tightly spaced trees

 Extremely damaging disease.  Only occurs on Douglas-fir.  Intermountain provenances most susceptible. (Lincoln)  Distribution: Australia Europe North America  Endemic in natural range (PNW).  Introduced to other areas.  PA in Susquehanna Co.

 Needle tips of current and/or previous years needles yellow and gradually brown during late winter  No distinct margin between healthy and infected needle  Mottled appearance September

 Looks like drought stress or winter burn.  Needles eventually defoliate and leave interior of tree bare.  Stunted growth.  Loss of vigor.  Some growers report almost complete needle loss to young trees and subsequent death.

Management:  Fungicides used for management are protectants, so the product needs to be applied to new growth to prevent infection.

Management:  Carefully scout symptomatic trees in spring for bud break and fungus sporulation. Four fungicide applications (most commonly Bravo) #1 - when 1st trees in plantation break bud. #2 - one week after first application. #3 - two weeks after second application. #4 - three weeks after the third application.  4th application necessary only if spring is prolonged by cool, wet whether, or Swiss needle cast is detected.

 All fungicides are protectants.  Timing of first application is critical. Carefully scout symptomatic trees in spring for bud break and fungus sporulation.  Five fungicide applications * #1 - when trees in plantation break bud. #2 through #5 – 7 – 10 day intervals – Carefully monitoring weather conditions – Later sprays most important for Swiss Paul Shealer, 2014

 Plant coastal varieties - Shuswap  Weed control for good lower branch coverage  Removal of old/overgrown trees  May take 2 -4 years to “clean up a tree”  Good timing Monitor for bud break Weather conditions (prior to wetting)  Right product  Thorough coverage

 Disease infecting a season’s new shoots  Infection begins in spring and continues to spread throughout season.  Spread in wet weather

 Hosts: Austrian and Scotch pines (Damage potential severe), Douglas-fir  Symptoms: browning of twigs starting at bud, wilting of new growth, black fruiting bodies found under bark

 Management: For light infestations, prune out damage and remove from field. Be careful not to uses same pruners to clip healthy twigs. For heavier infestation, make a few applications beginning at bud break. Bravo (chlorothalonil) is not effective against Diplodia. – Heritage, Quadrid (azoxystrobin) – Topsin (thiophanate-methyl) – Kocide, Champ (copper hydroxide)

 Leaders become stunted, needles drop and eventually die.  One possible cause of death is canker formation.  Temperature swings in winter can cause wounding on leaders.  Where these wounds occur, diseases can enter and form cankers.  Could also enter through pruning wounds. Jill O’Donnell, Michigan State University Extension

 Fungicides not effective in controlling secondary diseases entering.  Don’t plant Douglas in frost pockets.  Prune leaders in late summer or early fall to allow plenty of time for wound to heal.  Prune leader back to the branch collar without injuring the collar. * Recommendations made by Jill O’Donnell at Michigan State University Extension. : USDA Forest Service Archive, USDA Forest Service, Bugwood.org

 Hosts: Douglas-fir, Pine, Spruce – Any tree Cathy Thomas, PA IPM Program, PDA

Late May – June: Larvae exit bags on silk threads. Sandy Gardosik, Entomology Department, PDA

Bagworm Early damage

OVERWINTER – Eggs are protected in the case over winter and through spring. LATE SPRING / MAY – Larvae hatch inside the cases and exit to begin feeding on needles. THROUGHOUT SEASON – Larvae continue to feed and grow. Early Fall / September – Larvae pupate and the male moths exit cases to fertilize the females in their cases. Fertilized females produce eggs. Spraytargetinglarvae

 Management: Physical – Remove bags from trees by hand before larvae emerge in late spring. Bio-Rational – Apply a Bacilus thuringensis (Bt) spray in early summer, targeting newly emerged bagworms. – Javelin, DiPel Chemical – Apply a registered insecticide at the time of bagworm emergence. Wait until majority have emerged to spray, and make one application. – Pyreth-it (Pyrethrin), Conserve & Entrust (Spinosad)

 Small, sucking pests  2 hosts: Douglas-fir – needles affected Blue Spruce – twigs & buds affected  Form protective waxy, wool-like coverings outside of gall

 On Douglas-fir Kinked needles Adult with eggs Fall/Early Spring: Nymphs with no wax

Nymphs on new growth Brian Schildt, PA IPM Program, PDA

Sandy Gardosik, Entomology Department, PDA

OVERWINTER – EARLY SPRING – Nymphs exposed on the needles. EARLY SPRING / APRIL – Nymphs mature into adults and develop protective waxy covering. CLOSE TO BUD BREAK – Adelgids develop eggs. AFTER BUD BREAK – Eggs hatch and nymphs move to new growth. This process continues through the season. OCTOBER – Nymphs will settle for the winter on the needles (uncovered). Spraytargetingnymphs

 On Colorado Blue Spruce

 Management: Treat with dormant oil in late fall or early spring when trees are dormant. Or apply registered insecticide in early October or before bud break in Spring to target overwintering nymphs. – Damoil (Mineral Oil), M-Pede (Insecticidal Soap), Provado (Imidacloprid), Talstar (Bifenthrin), Movento (Spirotetramat) – Additional control options on the fact sheet Insecticides & Miticides for Christmas Tree Pests.

Sandy Gardosik, Entomology Department, PDA

 Light orange, fly-like midge  Long, delicate legs  Tiny – adults are 3 mm in size  Carries out life cycle by forming galls inside Douglas-fir needles.

Tracey Olson, Plant Pathology, PDA Sandy Gardosik, Entomology Department, PDA

 Douglas-fir needle midge is spread throughout much of the United States.  Has been a large issue in the northwestern US.  If Douglas-fir is present, potential for DFNM is there.

Adults emerge at end of April – early May. Eggs are laid about 5 days after adult emergence and hatch about 3 days later.

Gall becomes evident about 3 weeks after larvae enter needles. About the 4th week in May. Infested area swells on bottom side of needle.

Larvae begin exiting needles in mid November. Midge pupate and overwinter in the soil.

OVERWINTER - Pupae are in the ground at the base of a tree. BUD BREAK / APRIL – Adults emerge to mate and lay eggs in the new buds. About 5 days after emergence, eggs are laid inside the buds. EARLY SUMMER - Galls in needles become noticeable as swollen, bent areas. NOV/DEC – Larvae exit needles and drop to ground to pupate Spraytargetingadults

Look alike: Cooley spruce gall adelgid Sandy Gardosik, Entomology Department, PDA

RHABDOCLINENEEDLE MIDGE Sandy Gardosik, Entomology Department, PDATracey Olson, Pathology Department, PDA

Detection: Emergence Traps  Monitor adult emergence if infestation is high Scout Douglas fir in fall to detect infestation  Simple Construction: Cardboard Box (keep flaps for anchoring) Mayonnaise or Peanut Butter Jar. Duct Tape  Place at base of previously infested trees.  Put traps out April 1 st.

Adult Emergence Trap

Traps should be placed on the side of the tree where the most damage was found

As bud break approaches, check traps daily. Sandy Gardosik, Entomology Department, PDA

 Look for swarming midges in fields with previous infestations.  DFNM will fly around the buds.

Management:  Because of long, thin ovipositor, females can lay eggs in buds before full bud break.  Usually too late to wait until 10% bud break  Orthene label allows for application up to 2 weeks before bud break. Acephate (Orthene) Azadirachtin (Azatin) Chlorpyrifos (Lorsban, Whirlwind ) Lambda-cyhalothrin (Lambda T, Warrior)

 SYMPTOMS: Yellowed needles on lower branches, beginning at trunk Damage moves upward as population increases. Scale coverings on the underside of the needles Tree may appear flocked Premature needle drop Eventual branch and limb dieback and death of tree with severe infestations Fiorinia externa (Ferris)

 HOSTS: Douglas-fir Hemlock Spruces True Firs Pines (less common)

MARCH – MAY - As scales develop, male and female armor differs. Male scales mature into adult winged insects Oval females produce protective “elongate” covering. THROUGHOUT SEASON – Eggs are laid within female casing. LATE MAY – Crawlers begin to appear & continue to throughout season NOVEMBER - MARCH – Scale overwinters in several stages FEMALE MALE Sprayactivecrawlers

 LIFE CYCLE: Similar to Cryptomeria, but all stages may be present at anytime through the season. Crawlers can be active in April as soon as temperature warms, but are most prevalent in Late May / Early June.

MANAGEMENT: Method supported by Penn State research:  When crawler numbers increase in Late May or Early June, begin spray program of 3 applications every 4 weeks, or 4 applications every 3 weeks with a registered insecticide. (This may not be necessary every season.) Method supported by Connecticut research:  A single basal trunk application of Safari prior to bud break Alternative:  Some growers have found success with only 1 or 2 sprays of the newer product Movento

 Dioryctria moths Zimmerman Pine Moth - Dioryctria zimmermani (Grote) Fir Coneworm – Dioryctria abietivorella (Grote)

 Hosts: ZIMMERMAN - Pines (Scotch, Austrian, Eastern White), Douglas- fir and spruce. FIR CONEWORM - Douglas-fir, true firs, a variety of spruces, pines and hemlocks.  Larvae feed inside the trunk, commonly at the site of a wound or a limb junction.  Cause lots of sap flow and weakening / breaking of limbs. Rayanne Lehman, PDA

 Damage: Large amounts of sap running from wounds. Large amounts of frass (excrement) found at wound site. Dead or dying branches or leaders of trees, but no wilting. Sam Lovenwirth, PDA

 Management: Mechanical - Removing and destroying infested trees before adult emergence. Should be done in early to mid-July. Chemical –  Zimmerman: Early Spring Application – targeting larvae before they move inside the trunk (April); must penetrate foliage to the trunk.  Fir Coneworm: Mid Spring Application – targeting adults before they can lay eggs (May). * Has been attempted by growers but not tested by research. – PRODUCTS – dimethoate, chlorpyrifos, endosulfan, Bt (Dimilin)

 Sarah Pickel Phone: Address: PA Department of Agriculture 2301 North Cameron Street Harrisburg, PA  Christmas Tree Scouting Report Provide me with your to be added to distribution list List. Website: Hotline: PENNIPM