Northeastern forest pest reporter

Historic, Archive Document

Do not assume content reflects current
scientific knowledge, policies, or practices.

No< 2 August 14, 1961

FOREST INSECTS

The probability of insect attack in a given area is affected by many factors.
Some factors, such as the relative abundance of the insect and the time of the year,
are obvious and routinely incorporated into the planning and conduct of surveys and
control operations every year. Others, such as tree vigor and location with respect
to sources of infestation, are generally recognized also. Less well understood are
the changes brought about by the insect itself. Here, the entire micro-environment
can be affected as well as the condition of the host tree. The insect and the tree
or stand are in a continual dynamic state, and the changes that do occur are impor-
tant because they directly and indirectly determine the probability of attack and
subsequent injury by the insect.

SPRUCE BUDWORM (Choristoneura fumiferana). Aerial spraying in northern Maine was
completed on June 26 this year with the follow-up survey of survival being under-
taken 7 to 10 days later. The aerial survey of current defoliation was conducted
by Maine Forest Service personnel July 7 and 8. The regular egg mass survey was
initiated July 31 and will be completed in several weeks. Infestations expected
in 1962 will be delineated when the data of the aerial and egg mass surveys are
compiled and summarized.

PINE SAWFLIES A pine sawfly (Neodiprion sp. ) is reported more widespread on
pitch pine this year in Massachusetts in the towns of Wareham, Rochester, Carver,
Plymouth, and Bourne. Many egg masses of the red-headed pine sawfly (Neodiprion
lecontei) are expected to hatch and cause damage to young red pine in a planta-
tion near Harrisville, Lewis County, New York. In Virginia, heavy defoliation of
pines is expected also in several areas. Pine sawflies (unidentified) have been
heavily attacking 3- to 5-year-old loblolly pine in Somerset, Wicomico, and
Worcester Counties, Maryland, The introduced pine sawfly (Diprion similis) was
observed in light local infestations in Strafford County, New Hampshire. A

Neodiprion sp. severely defoliated pitch pines near Londonderry, N. H. ; whereas
the larvae were very abundant, the cocoons were very sparse (indicating either a
much reduced population or failure to search for the cocoons in the right places).
The red pine sawfly (Neodiprion nanulus) is reported locally abundant in eastern
Maine .

WHITE-PINE WEEVIL (Pissodes strobi ) . Damage by this insect to white pine appears
relatively unchanged from last year in Rhode Island. Preliminary results indi-
cate good control of the weevil on 150 acres of white pine in western Pennsylvania
using a back-pack sprayer and DDT. Damage to Norway spruce by the weevil has been
heavy particularly at Cook Forest, Clear Creek, and other State Parks in western
Pennsylvania. On the Allegheny National Forest approximately 700 acres of Norway
and white spruce were sprayed in April by helicopter with DDT for weevil control.

A complete check on the results of this control project will be undertaken in
August or September. Continued heavy damage to white pine in New York State is
reported. Current control recommendations are available on request from the
Forest Insect Laboratory in New Haven. An experiment at New Haven to test the
effectiveness of lindane and malathion with three different extenders applied by
mistblower and hydraulic sprayer showed that lindane was definitely more toxic
than malathion and reduced feeding by adult weevils much more markedly. Aroclor
5460 extended the toxic effect of both insecticides most efficiently. However,

Rex Wall Size (available in any paint or hardware store) was equally effective
in reducing feeding. As egg laying by the weevil in the spring involves chewing
an egg niche in the bark of the leader, this material might provide satisfactory
protection with, or even without, a toxicant.

PINE LEAF APHID (Pineus pini foliae) . A recent report from Vermont indicates that
gall formation on red spruce was late (May 20) this year and very spotty. Several
small scale tests using DDT, Sevin and malathion apparently revealed that these
insecticides were not very effective in preventing the gallicola form of this
insect from becoming established on white pine. The test was designed to simulate
aerial sprays by ground equipment — this is difficult to do. In eastern Maine,
continuing heavy infestations are found on white pine. In New Hampshire, this
insect is relatively abundant in all but the southern tier of counties. Parti-
cularly severe damage to white pine has occurred at Hanover and Passaconway.

Other gall aphids were fairly numerous on spruce in the northern part of the State,
making identification of the pine leaf aphid more difficult.

RED-PINE SCALE (Mat suco ecus resinosae) . This has been found at four other loca-
tions in northern New Jersey — at Demarest (Bergen County), Ringwood (two spots
just north of Wanaque) , and Mahwah (Bergen County, at New York Line).

EUROPEAN PINE SHOOT MOTH (Rhyacionia buoliana) . In Indiana, Cambria, and Armstrong
Counties, Pennsylvania, this insect has been especially serious in red pine plan-
tations. Damage has been so serious in the southern tier counties in Pennsylvania
that planting of red pine has been discouraged, as has been the case in northern
New Jersey and southern Connecticut. The shoot moth is present again in the coas-
tal area of southern Maine. There is no record of this insect from New Hampshire —
observers should be on the lookout for it, however, in the coastal portion and per-
haps elsewhere in Strafford and Rockingham Counties.

SOUTHERN PINE BEETLE (Dendrocto nus frontalis ) . A cooperative aerial survey by
Delaware, Maryland, Virginia, and the U, S. Forest Service over the Delmarva

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Peninsula revealed some additional beetle activity around the areas noted last year.
The survey was conducted from June 26 through June 30. Since new attacks were
found in about three-fourths of the 1960 areas in Virginia and Delaware, it was
recommended that another aerial survey be flown this fall to record any further
changes in these infestations.

MISCELLANEOUS INSECTS ON CONIFERS The pine bark aphid (Pineus strobi) is re-
ported less severe on white pine in western Pennsylvania this year — in Rhode
Island infestations are increasing on the same trees infested previously. The
balsam fir sawfly (Neodiprion abietis) is reported common in survey collections
from northern and eastern Maine. Local infestations of the larch sawfly (Pris-
tiphora erichsonii ) on larch and the yellow-headed spruce sawfly (Pikonema
alaskensis) on spruce are also reported from the same general area. Several
species of leaf miners have been heavily damaging northern white cedar in central
Maine. The European spruce sawfly (Diprion hercyniae) is reported scattered on
spruce in eastern Maine. Ami area of 4 acres of white pine near Middlebury, Vermont
was so heavily infested with the pine needle scale (Phenacaspis pinifoliae) that
aerial spraying with two pounds of malathion in about eight gallons of water with
Plyac as a sticker was carried out on May 27. No new crawlers were observed on
the current growth on July 17. Turpentine beetles (probably Dendrocto nus tere-
brans) are causing some mortality of scattered pines in Lunenburg, Amelia, Camp-
bell, Princess Anne (10 trees on 5 acres), and Isle of Wight (2 trees on 10 acres)
Counties, Virginia. Most damage has been found in loblolly, shortleaf, and
Virginia pines. Ips bark beetles have caused scattered mortality of pines through-
out Virginia. Pales weevil (Hylobius pales) has caused some shortleaf and loblolly
seedling mortality in Amherst and Nelson Counties, Virginia and has also caused
some mortality of white pine seedlings in western Pennsylvania. The pine false
webworm (Acantholyda erythrocephala) is reported light on Austrian and red pines
in the Lewis County Experimental Forest, New York. Infestations of the eastern
spruce gall aphid ( Che rme s abietis) are reported throughout the region, A heavy-
infestation of the pine gall weevil (Podapion gallicola) is reported in the Pack
Forest, Warren County, New York. A moderate infestation of the Saratoga spittle-
bug (Aphrophora saratogensis) is reported on 50 acres of red and Scots pine in
Clarion County, Pennsylvania.

NOTE : In addition to releases on the Green Mountain National Forest in

Vermont the predator of the balsam woolly aphid, Laricobius erichsonii , was also
released on state and private land in Vermont during May (see July 12, 1961 issue
of PEST REPORTER).

GYPSY MOTH (Porthetria dispar) . Widespread egg masses found last winter in New
Hampshire indicated subsequent widespread defoliation, which did not actually
occur this spring. Only localized heavy defoliation was found. In Maine,
’’hundreds” of acres of hardwood were stripped in the Waterboro, Lyman, Alfred
areas of York County. In the Acadia National Park approximately 1,000 acres
were heavily defoliated, and a total of 1,800 acres were defoliated near Tunk Lake
(TIO S.D.) and Beech Hill (SW corner T24 M. D. ) Washington County, Maine. In Ver-
mont the insect is definitely increasing in the Champlain Valley. In New York it
is also increasing in Washington, Saratoga, and Warren Counties. This survey is
as yet incomplete, however. In Connecticut male and female pupae were found for
the first time in the towns of Avon, Canton, East Windsor, and West Granby.

Exploratory tests with the new synthetic sex attractant are being conducted
by entomologists of the Connecticut Agricultural Experiment Station, New Haven

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Laboratory, and Plant Pest Control Division, A. R. S. There are some interesting
possibilities in using this material for control purposes.

MISCELLANEOUS INSECTS ON HARDWOODS Light cankerworm damage is reported from
Adams, York, Franklin, Mifflin, Juniata, Perry, Carbon, Luzerne, and Bedford
Counties, Pennsylvania, The elm leaf beetle (Galerucella xanthomelaena) is
generally abundant on elms throughout the Northeast, The mountain ash sawfly
(Pristiphora geniculata) is generally common throughout Maine on mountain ash,

The birch casebearer (Coleophora salmani ) is relatively abundant in northeastern
Aroostook County on white birch. Damage by the gregarious oak leaf miner (Camer-
aria cincinnatiel la) is reported on oaks near Peterburg and in Dinwiddie and
Prince George Gounty, Virginia. The ugly nest caterpillar (Archips cerasivorana)
is reported from several locations in the Champlain Valley of Vermont. It is also
reported from Franklin, Clinton, and Essex Counties, New York. Several small in-
festations of the satin moth (Stilpnotia salicis) occurred on poplar in the towns
of Chazy and Champlain, Clinton County, New York. Oak leaf roller (Argyrotoxa
semi pur pur ana) infestations continue for the sixth consecutive year on scarlet
and red oaks near Williamsport, Pennsylvania.

FOREST DISEASES

Weather conditions since the first issue of the PEST REPORTER have been
moderately fair for disease development. Winds have been generally light so their
effect on spore dispersal has probably been less than usual. Temperatures have
been lower than average, especially from mid-June to mid-July. In southern Connec-
ticut night temperatures were generally in the low sixties and the highs have aver-
aged in the mid -seventies , The cooler than average night temperatures have prolonged
the early morning dew periods. From mid-July, night temperatures were generally in
the low seventies, and the highs from the high seventies to mid-eighties. The last
week of July had above-average temperatures ranging from the high seventies and low
eighties to the mid-nineties. New York City, for example, reported records were
broken for a number of consecutive days when recorded temperatures were 90° or above.

Rains were moderately well scattered, although somewhat erratically distri-
buted — but they were generally light. We have had no serious droughts, and rains
though light generally terminated what might have developed into moderately severe
dry periods. On the whole, July was rather dry with some rain recorded on 10 days,
most of it coming in mid-July. We have had perhaps more than the average number of
cloudy days, and the temperature-humidity index has been on the uncomfortable side,
especially during the latter part of July.

It is expected that foliage diseases, previously retarded by the cool spring
weather, and largely unnoticed due to early insect defoliation, will be more promi-
nent from now on. The most conspicuous diseases reported for this issue are wi 1 1 s ,
Cytospora branch cankers on spruces, various diebacks and declines, and unexplai ned
troubles in young conifer plantations, including the multiple leader condition.

We have a couple of follow-up reports of the late frost injury reported in
the first issue. One tells of frost rings resulting from the severe late frost.

In West Virginia frost rings in red pine were present where damage to beech was
evident at high elevations. The frost rings were less pronounced at somewhat lower
elevations where beech injury was slight or absent. No frost rings were detected
in rec^pruce or beech. The other report from Connecticut tells of receiving a
number of inquiries from people about the new growth on oak, etc. The new growth.

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from frost injured twigs or from insect defoliation, has a reddish color, is
mainly limited to branch ends, but is scattered throughout the tree crowns. It
has been very conspicuous this year.

LEAF AND SHOOT DISEASES Leaf spot diseases are of minor importance throughout
the region. In fact, none of the foliage diseases have been alarming. A Pennsyl-
vania report says leaf spotting is light on red and sugar maples. Leaf spot of
red maple is general in Henry County, Virginia. A leaf spot on boxelder, caused
by Septoria aceris, has been noted in Vermont, and New Hampshire reports that a
Septoria leaf spot of paper birch seedlings is common. From eastern Massachusetts
we received word of an unidentified bacterial leaf spot of tulip, and a bacterial
shothole, caused by Xanthomonas pruni , affecting peach and plum. Also that haw-
thorne leaf blight, caused by Fabraea maculata, previously reported, is serious
causing approximately 40 percent defoliation. Total defoliation is expected on
some varieties which have not been sprayed. Maine also reports that hawthorne leaf
blight is abundant on some ornamental hawthornes. Oak leaf blister CTaphrina
coerulescens ) has been noticed in nursery plantings of red oak. Leaf scorch of
sugar maple, especially on dieback affected trees, is frequent and serious, as
noted along Route 20 from Boston, Mass, to the central part of the State.

Anthracnoses are reported as of little importance this year. Reports tell
of light infections on red and white oaks in Clearfield, Jefferson, and Clarion
Counties in Pennsylvania, It is present on white oak and sycamore in western Mary-
land, An eastern Massachusetts report tells of having received specimens of
Gloeosporium apocryptum on sugar maple and of Gnomonia caryae on hickory. A previous
report of ash defoliation in the Augusta area of Maine has now been identified as
ash anthracnose, and that considerable defoliation occurred in June in Kennebec
County.

Shoot and Twig Blights. — Willow blight is reported from Berkshire County,
Massachusetts, and is very common in Maine this year. Diplodia twig blight is
said to have practically eliminated some trees of Austrian pine that have borne
light to moderate infections of the fungus. It seems particularly bad along the
Hudson River Valley. This disease may be responsible for the Scotch pine dieback
prevalent in Indiana, Cambria, and the south-central counties in Pennsylvania. It
is quite bad in 25- to 30-year-old plantations, and salvage cuttings have been made
whenever markets permit. Reports of juniper blight, Phomopsis juniperovora , have
been received from eastern Massachusetts and from Virginia where it occurs on 2-year
seedlings of red cedar in the New Kent nursery.

RUST DISEASES Blister rust (Cronartium ribicola) infections of Ribes have developed
very rapidly in New York. On many areas infection is so heavy that leaves have
turned completely yellow, making Ribes infections easy to spot. Telia are present
at an early date, resulting from the very favorable weather conditions. A Pennsyl-
vania report states that Ribes infection, so far, has been light to moderate, but
weather has been favorable and a gradual buildup is on the way, presaging ultimate
heavy infection. A report from Virginia tells of one-tenth of the trees in a
plantation in Highland County being infected. Another Virginia report speaks of
several small areas of blister rust in Highland County — areas never under control.
Heavy Ribes infection has been observed in Augusta and Rockingham Counties.

Blister rust cankers on western white pine in the vicinity of Maryland, New
York have not responded to Acti-dione treatment (150 p.p.m, as basal spray). Pre-
liminary results of spraying Ribes in Pennsylvania are encouraging -- both fuel
oil base and water mixtures have been used. Blister rust control has been good
in all control areas.

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other rusts. — In addition to blister rust, other rusts reported include a
gall rust on Virginia pine in Henry County, Virginia; cedar apple rust in Smyth
County; a needle rust on loblolly in Norfolk County, and telial stages of fusiform
rust on oaks from New Kent. Ash leaf rust, Puccini a sparganioides , is present
along the coast, but not serious in New Hampshire, The previous report of ash rust
in southern Connecticut continues to be severe, as observed on two large trees.

Both trees have shed about 75 percent of their leaves, and aecia have been blossom-
ing abundantly, shedding fresh spores during every period of rain since early spring
through July into August — a long period for aeciospore production.

WILT DISEASES Dutch elm disease (Ceratocystis ulmi) is widespread and now quite
evident throughout the Northeast, It became especially evident during June and
later. A Pennsylvania report states it is particularly apparent in western areas
of the State. Dutch elm disease is frequent and occurs throughout Massachusetts.

New Hampshire reports DED is taking a heavy toll around the Laconia area and another
report from the State says the disease is about the same as in the past few years.
Virginia reports DED present in Fauquier County. A report from western Maryland
tells of an elm which turned completely brown, but the cause has not been diagnosed
as DED. Phloem necrosis appears to be a likely suspect.

Verticil lium wilt (Verticil lium albo-atrum) may possibly be worse this year
than last. We noticed a sudden outbreak of the disease affecting Norway maples in
Hamd en , Conn .

Oak wilt (Ceratocystis fagacearum) has been noted in western Maryland. Penn-
sylvania reports that oak wilt has been slow in appearing this year, although
latest survey reports indicate at least as many infections as normal, with an
upward trend possible. In Virginia oak wilt has been found on the George Washing-
ton National Forest, in Rockingham, Shenandoah, Augusta, Highland, Bath, and Page
Counties .

CANKER DISEASES Cytospora canker of spruce (Cytospora [Valsa] kunzei) is one of
the more noticeable diseases at this time. One report states, "The incidence of
Cytospora on spruce, particularly Colorado blue spruce, has taken a sharp upturn.
Many large trees which to all appearances have remained untouched by the disease
suddenly have entire sides going out from the simultaneous attack on many branches,”
Light infections of the disease are reported on Japanese larch on New York Refores-
tation Area Jefferson No. 3.

Maple cankers. — We have received word that a maple canker, associated with
Pyrenochaeta sp. , was collected in New York State from Cortland County. This
canker was first reported in the second issue of the PEST REPORTER, Aug. 10, 1959,
from Pennsylvania, No one knows what part this maple canker plays in the complex
of diseases included in the maple dieback and decline. It appears to differ in
some respects from the condition so prevalent in New England roadside trees,
especially in the degree of stem and branch cankering. Dr. Stambaugh of Penn State
University has worked on the disease in Pennsylvania, and early this spring was
asked to prepare a brief statement of his findings for the PEST REPORTER. [Come on,
Bill, — we will put your contribution in our third issue!] Dr. Rich of the Univer-
sity of New Hampshire says, "Our biggest problem is the decline of our roadside
maples.” He says a graduate student is being assigned to work on this problem
starting July 1. Cytospora canker of maple is reported somewhat more prevalent
and more severe in 1961 than in previous years, in New Hampshire.

Beech-scale-Nectria. --Word from New Hampshire on this disease says that
the sporodochial stage of the fungus component is common and these white clusters
of the fungus should not be confused with the scale, which they somewhat resemble.

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The mycoparasite , Gonatorrhodiel la highlei , seems to be at its peak at this time
and can commonly be seen. It was observed while cutting beech that many trees
had an abundance of scale and Nectria in their crowns, with stems being relatively
clean.

Other canker diseases reported for this issue include some reported pre-
viously, Among them are Tympanis canker on low vigor planted red pines; an unknown
basal canker on white pine in a plantation in the DeRuyter area of New York; and,
Caliciopsis canker in western white pine in the vicinity of Maryland, New York.

ROTS Pomes annosus. — Reports continue with a report from Virginia of slight to
severe damage on loblolly pine in Albemarle and Orange Counties and suspected in-
fections of red cedar in Louisa County, Word from Rhode Island says _F. annosus
infected spots continue to enlarge normally although no new infections were noted
in stands being marked, A Vermont report tells of additional infections discovered
in a 40-year-old red pine plantation in Windham County, and another speaks of the
lush growth of sporophores noted in New York State, A report from Massachusetts
tells of a 40-year-old, 8 x 8-foot, red pine plantation west of Whately that had
been thinned once in 1953. Although _F, annosus was fruiting on stumps, no damage
was observed among the standing living trees. Word from Connecticut mentions a
planting of white spruce for Christmas trees. The planting had been made on light,
sandy soil formerly occupied by pitch pine. It is now 5 to 9 years old and F.
annosus is present and fruiting on some of the affected trees. It is quite unusual
to find evident damage to such young trees. We may have additional information
concerning this infection for our next issue of the PEST REPORTER. Finally, we
would like to call attention to the F. annosus publication, available for distribu-
tion, listed at the end of this issue.

Other rots. --At this time many wood rotters are fruiting abundantly. Fur-
ther information from Vermont concerning a serious Armillaria mellea infestation
of red pine on the Groton State Forest is at hand. Mortality has continued. Some
8 to 10 separate infections have created large openings which are now coalescing,
making the losses from A. mellea much more evident. A report on root rot damage
by Polyporus tomentosus to a Norway spruce planting in the Poughkeepsie area of
New York was received. This information may have been previously reported from
another source. Finally, damage by Stereum sanguinolentum, which entered Norway
spruce through pruning wounds, is reported from the Alder Creek Reforestation Area
of New York.

DIEBACKS The most conspicuous tree troubles are the diebacks and declines. They
are widespread and serious, affecting a number of tree species. The most alarming
in the whole Northeast are ash and maple dieback and decline. Reports of diebacks
for this issue are notable for the number of reports received, the seriousness of
the troubles, and their wide distribution.

Ash dieback. — The trouble seems more intense than last year. The number of
trees involved and the rate of deterioration seems to have increased considerably.
Many trees in central and western Connecticut are exhibiting symptoms where none
were observed before the current season. Lead and dying ash occur around Patterson,
Clifton, Newark, and East Orange in New Jersey as observed in mid-July. Ashes in
the vicinity of our large cities are declining rapidly as noted around Philadelphia,
Pa. and Boston, Mass. Aerial observations in areas of known high concentration,
such as the Albany-Poughkeepsie area of New York, reveal dead and dying ash easily
recognized from the air due to typical tree form and the orange color of infected
crowns. There is a high degree of seedling deterioration, even in stands where the
ash overstory is comparatively healthy. Other reports came from western Maryland,

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Pennsylvania, eastern and the Berkshire region of Massachusetts, and from New
Hampshire, Cankers of Cytophoma pruinosa , commonly associated with ash dieback
elsewhere, were not seen on the New Hampshire affected trees.

We have word that two graduate students of Syracuse University have
recently been assigned to work on the problem of ash dieback. It is very encour-
aging to learn of any investigations of the dieback problems. We also hear that
some decay fungi have been isolated from the roots of declining ash, including
one identified as Ustulina vulgaris .

Maple dieback. — Maple dieback and decline is very bad this year. After
two years of dubious improvement, the maples appear to be on the downhill road
again. Maple dieback figured prominently in the reports for this issue and most
seem to agree the condition of maples is worsening. The sad state of the maples
is exemplified by one report of young maples 4 and 5 feet in height dying along
roadsides in some places. Nearly all contributions for this issue of the PEST
REPORTER mentioned maple troubles of roadside trees — how are the woodland maples
doing?- [Also see remarks under "maple cankers."]

Other dieback conditions. — Oak mortality seems more of a problem in the
southern part of our territory than further north, although a note from Virginia
states that oak dieback (which has been active in recent years on portions of the
George Washington National Forest) seems dormant, with only an occasional tree seen
now. We suspect, however, that these oak troubles may be more widely reported in
the future. Oaks have suffered heavy insect defoliation in the past two years,
and even now many have scattered dead branches in their crowns. Other declining
conditions and mortality is reported, some mentioned previously. For example, a
New York report mentions the mortality of white pine associated with heavy inter-
nodal resinosus ; also a decline of beech.

MISCELLANEOUS TROUBLES From Virginia comes word that chlorosis and decline of
pin oak is present in Lexington County; also that an Exosporium sp. has been diag-
from a dieback of red cedar in Hanover County; and that oak mortality from an un-
known cause is present. White pine needle blight is rather rare in New Hampshire.

Red maple is having its troubles. Large areas of red maple in and around the Hudson
River Valley look sickly with a yellow cast of the foliage. The foliage is thin and
the trees have a generally unhealthy appearance. Most of the trouble is in low areas
and along stream beds. It has been suggested that a higher than average water table
may be the cause. A thinning and discoloration of needles of large white pines in
the Cook Forest area of Pennsylvania has been reported. Also from Pennsylvania is
a report of smoke and industrial gas injury. Trees are being killed in the Susque-
hanna River Valley of Clearfield County. White pines and hemlock die first, then
evergreen ornamentals, followed by fruit trees, and now certain hardwoods. The
killing appears to follow a definite pattern up the river and in the direction of
the prevailing winds.

Vc Vc -k -k i< -k -k

A recent publication on Fomes annosus:

Mook, Paul V. and Harold G. Eno. 1961. Fomes annosus r What it is
and how to recognize it. Station Paper No. 146, Northeastern
Forest Expt . Sta. , Upper Darby, Pa. [Copies are also available
from the Forest Insect and Disease Laboratory, NEFES, 335 Pros-
pect St., New Haven, Conn.]

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