M. W. (Maulsby Willett) Blackman.

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Polume XVIII

May, 1918

Number 4






I. Notes on Insects Bred from the Bark
and Wood of the American Larch


II. On the Insect Visitors to the Blos-
soms of Wild Blackberry and Wild

Spiraea— A Study in Season-
able Distribution


Published Quarterly by the University
Syracuse, New York

Entered at the Postofflce at Syracuse as second-class mall matter

Volume XVIII

May, 1918

Number 4






I. Notes on Insects Bred from the Bark
and Wood of the American Larch


II. On the Insect Visitors to the Blos-
soms of Wild Blackberry and Wild

Spiraea —A Study in Season-
able Distribution


Published Quarterly by the University
Syracuse, New York

Entered at the Postoffice at Syracuse as second-class mall matter




To be had upon application by residents of the State

Technical Publication No. 1, 1914.

Preliminary Report on the Diseases of Fish in the Adirondacks:
A Contribution to the Life History of Clinostomun marginatum.
By Dr. W. M. Smallwood. pp. S-27.

No. 2, 191G.

I. A New Species of Pityogenes. By J. M. Swaine. pp. S-10.
II. Observations on the Life History and Habits of Pityogenes
hopkinsi Swaine. By Dr. ^I. W. Blackman. pp. 11-G6.

No. 3, 1916.

The Development of the Vegetation of New York State. By Dr.
William L. Bray. pp. 11-186.

No. 4, 1916.

The Relation of Mollusks to Fish in Oneida Lake. By Frank C.
Baker, pp. 15-366.

No. 5, 1917.

The Hardwood Distillation Industry in Nev\' York. By Nelson C.

No. 6, 1917.

Wood Utilization Directory of New Y''ork. By John Harris, Forest
Service, revised and rearranged by Nelson C. Brown and Henry
II. Tryon.

No. 7, 1917.

The Relation of Birds to the Western Adirondack Forest. By
P. ]M. Silloway.

No. 8, 1917.

The Black Zones Formed by Wood-destroying Fungi. By Arthur
S. Rhoads.





i Insects Bred from American Larch 3

, No. 9, 1918.

(^ The Productivity of Invertebrate Fish Food on the Bottom of

' Oneida Lake, with Special Eeference to Mollusks. By Frank

^ Collins Baker.

\J) No. 10, 191S.

I. Notes on Insects Bred from the Bark and Wood of the American
Larch. By M. W. Blackman and Harry H. Stage.

II. On the Insect Visitors to the Blossoms of Wild Blackberry and
Wild Spiraea: A Study in Seasonal Distribution. By M. W.




Ex Officio

Dr. James E. Day, Chancellor Syracuse University.

Dr. John Huston Finley, Commissioner of Edu-
cation Albany, N". Y.

Hon. Edward Schoeneck, Lieutenant Governor of

the Utate Syracuse, N". Y.

Hon. George D. Pratt, Conservation Commis-
sioner New York City.


Hon, Charles Andrews Syracuse, N. Y.

Hon. Alexander T. Brown Syracuse, N. Y.

Hon. John R. Clancy Syracuse, N. Y.

Hon. Harold D. Cornwall LowTT^ille, N. Y.

Hon. George W. Driscoll ■ Syracuse, N. Y.

Hon. Francis Hendricks Syracuse, N. Y.

Hon. Hendrick S. Holden Syracuse, N. Y.

Hon. Louts Marshall New York City.

Mr. Edward H. O'Hara Syracuse, N. Y.

Officers of the Board

President Hon. Louis ]\L\rshall.

Vice-President Hon. John H. Clancy.

Treasurer Hon. Hendrick S. Holden.








Chancellor of the University.

* HUGH POTTER BAKER, M. F., 1904 (Yale) ; D. Oec, 1910 (Munich),
Dean of the College; Professor of Silviculture.

FREDERICK FRANKLIN MOON, B. A., 1901 (Amherst) ; M. F., 1909

Professor of Forest Engineering, Acting Dean.

MAULSBY WILLETT BLACIO^IAN, A. B., 1901; A. M., 1902 (Kan-
sas); Ph. D., 1905 (Harvard),
Professor of Forest Entomology.

EDWARD F. McCarthy, B. S., 1911; M. S. F., 1916 (Michigan),
Professor of Forest Utilization.

•NELSON COURTLANDT BROWN, B. A., 1906; LL F., 1908 (Yale),
Professor of Forest Utilization.

J. FRED BAKER, B. S., 1902 (Michigan Agricultural) ; M. F., 1905,

Director of Forest Investigations.

LEIGH H. PENNINGTON, A. B., 1907; Ph. D., 1909 (Michigan),
Professor of Forest Pathology.

SEWARD D. SMITH, B. S., M. S. F., 1910 (Michigtui),
Director of State Ranger ScJbool.

JOHN WALLACE STEPHEN, B. A., 1907; M. S. F., 1909 (Michigan) ;

M. Pd., 1915 (Michigan Normal College),

Professor of Silviculture.

* On leave of absence.


C College of Forestry

CHARLES CHRISTOPHER ADAMS, B. S., 1896 (Illinois VYesleyan) ;

M. S., 1899 (Harvard); Ph. D., 1908 (Chicago),

Professor of Forest Zooloijij.

HENRY R. FRANCIS, B. S., 1910 (Massachusetts Agricultural College),
Professor of Landscape Extension.

SHIRLEY W. ALLEN, B. S., 1910 (Iowa State College),
Professor of Forest Extension.

HARRY P. BROWN, A. B., 1909; A. M., 1910; Ph. D., 1914 (Cornell

University) ,
Professor of Dendrology.

SOLOMON F. AGREE, B. S., 1896; M. S., 1897 (Texas) ; Ph. D., 1902

(Chicago) ; F. C. S.,

Professor of Dendrological Chemistrij.

ROBERT CRAIG, Jr., M. S. F., 1910 (Michigan),
Professor of Forestry at New York State Ranger Sciiool.

* REUBEN PARKER PRICHARD, B. S., 1907 (Dartmouth); M. F.,

1909 (Y^ale),
Assistant Professor of Dendrology.

LAURIE D. COX, A. B., 1903 (Arcadia College) ; S. B. in Landscape

Architecture, 1908 (Harvard),

Assistant Professor of Landscape Engineering.

HOWARD BLAINE WAHA, B. S., 1909; C. E., 1918 (Pennsylvania

State College),

Assistant Professor of Forest Engineering.

* IIENRY^ HARRINGTON TRYON, A. B., 1912; M. F., 1913 (Harvard),

Assistant Professor of Forest Utilization.

ERNEST G. DUDLEY, A. B., 1908 (Leland Stanford Jr. University) ;

1908-09 (Y^ale Forest School),

Assistant Professor of Forest Extension.


( Michigan ) ,
Assistant Professor of Forest Botany.

•■' On leave of absence.

Insects Bred from American Larch 1

CARL JOHN DRAKE, B. S., B. Fed., 1912 (Baldwin-Wallace) ; A. M.,

1914 (Ohio State University),

Assistant Professor of Forest Entomology,

HIRAM LEROY HENDERSON, B. S., 1915 (Michigan),
Assistant Professor of Forest Utilization.

* ALAN F. ARNOLD (Harvard) ,
Instructor in Landscape Engineering.

CARL CHESWELL FORSAITH, A. B., 1913 (Dartmouth) ; A. M., 1914,

Fh. D., 1917 (Harvard),

Instructor in Forest Technology.

HAROLD CAHILL BELYEA, A. B., 1908 (Mt. Allison Univ.) ; M. F.,

1916 (Yale),
Instructor in Forest Engineering.

EDGAR C. FEDDIE, B. S., 1917 (New York State College of Forestry),
Instructor in Landscape Engineering.

RAYMOND F. HOYLE, B. S., 1917 (New York State College of

FoDestry ) ,
Instructor in Forest Utilization.

MERLE R. MEACHAM, B. S., 1913 (Hiram College) ; B. S- in Ch. E.,

1914; Ch. E., 1916 (Purdue University),

Research Assistant in Dcndrological Chemistry.

(Fuller Fund)

ALVIN G. SMITH, B. S., 1915 (New York State College of Forestry),

Field Assistant in Forest Investigations ; in charge of Syracuse Forest

Experiment Station at Syracuse.

*WILFORD E. SANDERSON, B. S., 1917 (New York State College

of Forestry) ,
Field Assistant in Forest Investigations.

DON M. BENEDICT, B. S., 1917 (Michigan),
Laboratory Assistant in Botany.

C. F. CURTIS RILEY, A. B., 1901 (Doane College) ; B. S., 1905

Michigan) ; A. M., 1911 (Doane College) ; M. S., 1913

( University of Illinois ) ,

Special Lecturer in Animal Behavior.

* On leave of absence.

College of Forestry

Secretary to the Dean.

WALTEE W. CHIPJMAN, B. S., 1893 (Wabash College),

ELEANOR CHURCH, B. L. E., 1916 (Syracuse University),

EDNA E. \^^^ITELEY, B. L. E., 1916 (Syracuse University),.





M. W. Blackman, Ph. D., and Harry H. Stage, M. S.



By M. W. Blackman, Ph. D., and Harry H. Stage, M. S.

Several years ago the senior author was impressed by the
fact that in comprehensive reports upon forest insects, such
as those of Packard ('90), Hopkins ('93, '99) and Felt
('06) a considerable number of boring insects are recorded
from pine, spruce and several other conifers but only a very
few are reported from the American larch. For instance,
Packard ('90) mentions only three borers in larch — Den-
droctonus sp. (doubtless D. simplex), Hylesinus opaculus
(probably Polygraphus rufipennis) and T amicus (Ips) pini,
— although he treats at considerable length thirty-three in-
sects affecting the trees in other ways. Hopkins ('93) in his
Catalogue of Forest and Shade Tree Insects of West Virginia
mentions no insects from larch, while Felt ('06) lists but
three boring insects from larch — Leptura suh-liamata Rand,
Tomicus (Ips) pini Say and Tomicus {Ips) caelatus Eich.
More recent papers by Swaine ('11) and by Hewitt ('12)
dealing with larch insects list Demlrotonus simplex Lee,
Ips halsameus Lee, Dryocoetus autographus Ratz., Dryo-
coetus n. sp. and Ips caelatus Eich. as borers attacking
recently felled larches or trees weakened by the defoliation
of the sawfly.

As it was believed that this paucity of forms known to
inhabit the bark and wood in the larch was due at least in
part to lack of study of this tree as a host for boring insects,
it was decided to take the first opportunity of making such
a study. Such an opportunity w\as offered when the junior
author on his return from his home reported the presence
of many dying and dead larch near Crittenden, Erie county,


12 College of Forestry

^N". Y. He was persuaded to return immediately and to ship
to the laboratory a liberal amount of material showing as
great a variety of conditions as possible.

On account of the fact that the infested larch was at a
considerable distance from Syracuse (about one hundred
and thirty-one miles) the ideal method of procedure in such
studies — which should consist of field work and insectary
work so co-ordinated as to check each other and to give the
best results — were necessarily modified. The field work
was reduced to a minimum and all field observations were
made by the junior author at such odd times as opportunity
offered. However, the work was so planned and conducted
that the results obtained were in no Avay weakened. In fact,
in a study of this sort the field work aside from the actual
collecting of the infested wood, can be dispensed with much
more readily than the insectary work; which, on the other
hand, is indispensable because of the impossibility in the
present state of our knowledge of identifying the immature
stages of many boring insects.

The method followed consisted in bringing to the labora-
tory generous samples of various parts of infested trees. A
careful and full record of the character and history of each
lot was kept and each lot was placed in a separate breeding
cage. The cages were then placed out of doors so that the
conditions would be normal and as near as possible what
they Avould have heew if left iii their original location. The
breeding cage used consists of a strong, well-constructed
frame of 2 x 2 cypress. The top is covered with fine copper
wire mesh, while the sides are sheets of glass lowered into
grooves in the frame. To the bottom of the frame is attached
a metal flange which may either be fitted into an especially
constructed base or may be pressed do^vn into the soft earth.
In most of our work the latter method was used and this
was true of all of the outdoor breeding work. In these cages
the sticks were propped up with one end resting upon the
loose soil or embedded in it, and, except in very dry weather,
the wood absorbed enough moisture from the loose earth to
keep it in fit condition for the insects living within. When

Insects Bred from American Larch 13

the weather was too dry, water was occasionally sprinkled
on the pieces of wood to prevent conditions from becoming
too unfavorable. In any event the conditions were donbtless
as uniformly favorable as they would have been had the
material remained undisturbed in its natural environment.

The various breeding cages were examined daily and all
insects which had emerged were kept separate with full data.
As the exact source of each insect emerging was scrupulously
recorded it was an easy matter later to find the various sorts
of insects associated in the same pieces of wood and in simi-
lar wood from other trees or regions of trees. By supple-
menting such data with later study of the wood it is often
possible to secure evidence to establish either absolutely or
pro1)ably that certain insects bear the relation of parasite
and host to each other. Whenever practicable the exit hole
made by an emerging insect was found and marked with the
same lot number as the insect which came from there. Later
this burrow was opened and the character of the larval mine
and pupal chambers studied. Specimens of several sorts of
larvse were also taken at intervals; and, by a later careful
comparison of such records of adults, burrows and larvse as
was thus obtained, it was often j)ossible to connect absolutely
the various stages of the insect and the burrow it produced.

Description of Woodlot From Which the Larch was


With the exception of five pieces obtained from Wanakena,
]Sr. Y., all of the infested larch used in this study was secured
from near Crittenden, I^. Y. Crittenden is twenty-one miles
east of Buffalo, in the northwestern part of Erie county.
The woods from which the larch was taken is one of con-
siderably larger dimensions than is usually met with in that
section. The tract comprises about one hundred acres. The
larger part of it is owned by the JSTew York Central Rail-
road, the rest belonging to the adjoining farms.

The greater number of tree species in this track belong
to the climax forest type — the principal ones being hard-

14: College of Forestry

maple, beech and hemlock. On the higher areas a few white
pines are scattered among the hardwoods. Only in two areas
is the larch to be found. This tract of timber is practically
in a virgin condition, doubtless owing to the fact that it is
owned by the railroad. The area has apparently never been
lumbered and presents fairly good forest conditions — that
is the general conditions are excellent for tree growth.

As previously stated the larch is to be found in two
separated areas, a western grouj) having between thirty and
fifty trees, and an eastern one of between four and five
hundred trees. These two areas, which are lower and there-
fore moister than the- surrounding woods, are about two
hundred and fifty yards apart and between them is a dense
undergrowth consisting principally of jioison sumach, willow,
etc. In these areas, the larch predominates, the total number
of larch outnumbering all other species of trees combined.
All sizes of larches are present, from saplings up to trees
of about 14 inches D. B. II. Reproduction is good although
of course many of the smaller trees have been killed by
suppression due to shading.

A number of the larger larch trees (6 inches D. B. TI. and
up) have been weakened or killed each year for a number
of years by the removal of the bark by farmers. A decoction
made by steeping this bark is thought to make an excellent
spring tonic for horses and is used by the farmers of this
locality for that purpose. On all parts of the tract, trees
may be found from which more or less bark has been stripped
— these often being completely girdled from the ground up
to a height of about six feet. Trees completely girdled in
this way are of course killed immediately while trees stripped
of their bark on one side only, are not killed outright but
are greatly weakened. Both dead and weakened trees serve
as favorable breeding places for many different sorts of
insects, and it is with insects entering the tree under such
conditions that we deal with principally in this paper.

Aside from these trees killed or weakened by the stripping
off of the bark, the larch trees are under conditions such as
exist in practically virgin timber. This means that many

Insects Bred from American Larch 15

of the trees have reached their maximum growth — have
become matured — and some such trees are deteriorating
more or less rapidly. The presence of the excellent breeding
places offered by the girdled larch had resulted in an increase
of many insect enemies -^ several of which have increased
beyond the danger level. These are already successfully
attacking and killing not only the trees weakened by strip-
ping off part of the bark but also apparently have in the last
year or two killed a number of trees which were over-mature
but were otherwise uninjured. Indeed the conditions here
are in many respects similar to those reported by Swaine
('11) in a larch wood near St. Anne's, Que. There several
trees had been allowed to remain in the forest after felling
and these had acted as an excellent breeding place for a
number of scolytid beetles. Several of these were bred up
to such numbers that they were able to attack and kill the
living larches remaining. Of the five bark beetles l)reeding
in this larch, including Dendroctonus simplex, Ips halsameus,
Ips caelatuSj Dryocoetes autographus and Dryocoetes sp.,
Swaine considers only the first two as serious enemies of the

In the larch woods at Crittenden, the trees which had been
girdled by farmers in obtaining bark, had acted in much the
same manner — as incubators for a number of insects breed-
ing in dying or dead larch. The numbers of several of these
had increased l)eyond the danger level and they were able to
attack and kill trees over-mature and deteriorating. Several
of the trees from which most of the material for this study
was derived had apparently been killed in this manner.

In our study Trees I and X, as described later, were trees
weakened by over-maturing and their death is believed to
have been caused or at least much hastened by insect work.
Insects found in l)oth of these trees and in others under
nearly similar conditions included the scolytids Polygraphus
rufipennis and Eccoptogaster piceae, the cerambycid Asemum
moestum, always working very near the base of the tree, and
the melandryid Serropalpus harbatus. Demlroctonus sim-
plex was present in the bark of the basal twenty feet of the

16 College of Forestry

trunk of Tree I and of others examined in 1015 and 19 17^
but no signs of it were to be found in Tree X. There can
be little doubt that these insects working in the trunk
together with a number of borers which typically attack the
branches and the uppermost parts of the trunk such as
Neoclytus loiigipes^ Leptostylus sex-guttatus, Pogonocherus
inixtus, and the three species of Clirysohotliris — C. hlanch-
ardi, C. sex-signata and C. dentipes — greatly hasten the
death of many weakened trees. Melanopliila fulvoguttata
and Pliymatodes dhnidiatus are two other borers which are
often associated with them (the latter only in the lower
trunk) the first of these being a well-known enemy of weak-
ened spruces and hemlocks.

However, in the bit of woodland studied, these insects are
not working unhampered, but natural forces are at hand
which to some extent at least are tending toward the re-
establishment of the normal balance of forces and toward
the return to a more favorable condition for the larch. The
work of woodpeckers is much in evidence and seems to be an
efficient agency in reducing to some extent the numbers of
the brood of several of the more numerous bark-boring
insects. The birds seem to work in two ways — first by
making small conical holes through the bark into the sap-
wood to obtain the larvse of the larger sj)ecies of beetles
which have gone there to hibernate or to pupate, and sec-
ondly by removing practically all of the bark on large areas
of the trunk to uncover the brood (larvse, pupa and young
adults) of the bark beetles.

In some cases this work reached an unusual degree of
efficiency. Por instance one particular tree forty or fifty
feet high and about 14 inches in diameter, had had nearly
all of the bark removed from the ground to the very tip.
(Figs. 5, 6.) This tree had been heavily infested with
Dendroctonus simplex, Polygraplius rufipennis and other
borers, but only a small j)er cent of the original infestation
had survived the woodpeckers' thorough search for food. Of
course all of the infested trees had not been so thoroughly
gone over by the birds and a number of such trees had

Insects Bred from American Larch 17

apparently not been found by them at all. However, it is
safe to say that the woodpeckers were an efficient force, work-
ing toward the return of the normal balance of nature which
had been upset by the breeding of certain species of insects
above the danger level, due to the girdling, season after sea-
son, of a number of the larches by farmers. It is not believed
that the woodpeckers will be able unaided to reduce the
numbers below the danger level, as long as more trees are
girdled each year, but should this practice cease it is possible
that they would be able eventually to obtain the upper hand
and that conditions would return to normal.

Field Wokk

The field work consisted in locating the infested trees,
securing as many species of insects from them in the field
as possible, noting the condition and probable date of death
of the host tree, and securing all other data that was thought
might be of value. The fact that many of the trees had
been partially stripped of their bark by woodpeckers in
search of grubs was made use of in readily finding such trees
under winter conditions. The infested trees were cut down
and samples of the various parts of the trunk, of the top and
of the branches were selected. These different lots were
labeled and shipped to the laboratory where they were placed
in outdoor breeding cages as recorded previously.

The larger part of the material was obtained in the field
April 28 and 29, 19 IG, but from this time till April, 1917,
as occasion offered smaller lots were added. The material
placed in breeding cages and from which insects were bred
out was derived from eleven different trees showing a variety
of different conditions. Some of these samples were from
standing trees only recently dead, some from standing trees
dead 1, 2 or more years and some from trees which had been
blown over several years.

In the following pages these various trees are described
and the insects derived from each are listed. The material
from the first eight of these trees was shipped from Critten-

18 College of Forestry

den April 29, 1916, while the rest was obtaiuecl later, at
various times, as indicated.

Tree No. I was a large larch of about 14 inches D. B. H.
and about 50 feet high. It had probably died late in 1914
from unknown causes as it had not been stripped of its bark.
It was the one tree found in the spring of 1916 which con-
tained living specimens of Dendroctonus svni'plex. The lower
part apparently had survived longer than the branches as the
lower trunk was still somewhat sappy. This tree was rather
interesting from the fact that a large part of the bark from the
ground to the ti^D had been removed by woodpeckers in search
of various bark boring insects. Under the portions of bark
still adhering many sjDecimens of Polygraplius rufipennis
and Dendroctonus simplex still remained, but it needed only
a casual examination of the bark to discover that a very
large percentage had been uncovered and destroyed by the

More material was taken from this tree than from any
other one source. In one cage was placed the first segment
of the trunk, the lower end of which was taken from only 6
inches above ground. The bark on this section was riddled
by the burrows of D. simplex and P. rufipennis and the sap-
wood contained many larvae of Asemum moestum. These
latter were so numerous that just above the root 6 larvae
were taken from an area of the wood only 6 inches square.
In addition to these, three other species were bred from this
section of the tree: the buprested Melanophila fulvoguttata,

1 3 4 5 6 7 8 9 10 11 12

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