LETTERS TO MR. MARTIN, MR. GEORGE, MR. CONNOLD AND MESSRS. COLEMAN AND
SONS
Elm-bark and Ash-bark beetles—Roman remains—Bladder plums—The Silver
Y-moth.
A number of interesting and important fresh subjects are here concisely
treated in letters addressed to various British inquirers. These are
merely characteristic samples of a vast amount of correspondence for
which space could not be found.
_To the Rev. John Martin, Charley Hall, Loughborough._
TORRINGTON HOUSE, ST. ALBANS,
_April 2, 1897_.
DEAR SIR,—From your description of the elm-bark attack, I should
certainly think that the maggots were those of the Elm-bark
beetle, the _destructor_. If you do not feel certain after this
hint as to the nature of the infestation, and will send me a
little piece of bark, I will with pleasure examine it and report
to you. This infestation does not injure the timber of the tree.
The burrowings are mostly between the bark and the wood, though
necessarily there are a number of borings through the bark,
caused by the entrance and exit of the beetles. It would be
desirable to fell the trees, and peel off the bark and burn it.
The timber would be quite good (so far as this matter is
concerned) but if the bark is left, the maggots will in due
course develop to beetles and fly off to continue mischief
elsewhere. Further I would suggest that you should direct your
wood-superintendents to examine whether other elms show
shot-like holes in their bark—the sign of the presence of the
infestation. From your mention of the locality of the trees
being rather damp, I should conjecture that the trees were not
in absolutely perfect health, and this is the state of things
the beetle prefers for its attack. Injured boughs, or moderately
recently-fallen boughs, or, above all, felled elm trunks in
which there is still sap, but not flow enough to stifle the
little maggots, are the very headquarters of infestation, and it
is quite worth while to have such felled trunks peeled and the
bark destroyed, or they will be the nurseries of great mischief.
If you will supply me with more detail I will with great
pleasure give my very best attention.
[Illustration:
Beetle, much magnified (from “Forest Protection,” by W. R. Fisher);
workings in elm bark—from life.
FIG. 35.—ELM-BARK BEETLE, _SCOLYTUS DESTRUCTOR_, OLIV.
]
_April 5, 1897._
The little larvæ came safely yesterday and the specimens of bark
this morning. Necessarily when the attack has been going on so
long the burrows intersect each other so very much that they
cease to show the typical patterning or tracks, but I do not see
any reason at all to doubt that this is attack of the very great
elm-pest, the Elm-bark beetle. With regard to its infestation of
other trees besides elm, I have no knowledge of its ever
attacking either oak or ash, but on careful search I find that
one German writer records it as “sometimes” attacking the ash. I
greatly doubt this having been observed in our country. Our
ashes have, however, a bark beetle which tunnels much in the
same manner between the bark and wood, and of which the presence
may similarly be known by the shot-like holes in the bark. But
you would distinguish the difference in pattern of gallery at a
glance on raising the bark. As in the figure given, the
mother-gallery is branched. This Ash-bark beetle, _Hylesinus
fraxini_, does not do very much harm, for it chiefly attacks
felled trunks, or sometimes sickly or damaged trunks and boughs.
It is not to be compared in its ravages with the _Scolytus_,
well-named _destructor_. I am not aware of this ever attacking
oak.
[Illustration:
Workings, showing forked “mother gallery,” with larval galleries from
the sides.
FIG. 36.—TUNNELS OF THE ASH-BARK BEETLE, _HYLESINUS FRAXINI_, FAB.
]
_April 12, 1899._
You have certainly two kinds of bark attack present in the
specimens which you send me, but without the beetles I am not
able to say at all what species may have been doing the
mischief. I can say quite certainly that I do not see any signs
of the presence of the _Hylesinus fraxini_ (Ash-bark beetle),
but I have never, so far as I remember, seen the very long,
narrow borings, hardly wider than a thread of silk, which are a
good deal represented on the inner surface of one of your pieces
of bark.
There are two or three grubs in fairly good condition which I
have gently inserted into a burrow in the little bit of bark and
have put carefully aside in the little box, and if these
develop, we shall then know what we have to deal with. Perhaps
you may be able to secure some beetles in a month or two; it
would be of interest to make out the attack with certainty.
_November 7, 1899._
I have very carefully examined your beetle and find that it is
_Hylesinus crenatus_, sometimes known as the “Large Ash-bark
beetle” to distinguish it from _Hylesinus fraxini_, the
“Ash-bark” or the “Small Ash-bark beetle.” The life history of
each kind is stated to be the same, and I think, if I remember
rightly, that some time ago, perhaps a year or so, in the course
of our occasional correspondence, we have gone into the history
of the _fraxini_, but if not I should have pleasure in either
looking up the account in my Manual and sending the pages to you
or condensing the points.
There appears to me to be this difference in method of larval
proceedings: that whereas in the case of _fraxini_ the parent
galleries are formed somewhat in the shape of a T with a short
stem and long arms to the top, and the larval galleries placed
at right angles to the others (fig. 36), so far as I understand
this form is not followed by _crenatus_ fig. 38).
The beetle obviously pierces the bark, for the orifice
is visible; and in or under the bark there are the
mother-galleries, but I do not find the larval galleries
feathering as it were from these, and the figure before me gives
the idea of the body of larvæ having by their united attack
cleared a flat space from which they have continued their
solitary tunnels. Perhaps in cutting up your trees you may come
on some of these markings. It is said that there are two
generations in the year, of which the flight time of one is in
April and of the other in October. This species frequents oak as
well as ash, which is an important consideration, and I find it
noted as frequenting old trees. These are the main points which
I see about the history. I should think that if you find the
trees which you have felled much infested, it would be a good
thing to strip the bark off and burn it.
[Illustration:
1, Beetle, with wings expanded, and one wing-case drawn only in
outline, to show lower part of wing; 2, beetle as usually
seen—magnified; 3, smaller and paler variety; also lines showing
natural length.
FIG. 37.—GREATER ASH-BARK BEETLE, _HYLESINUS CRENATUS_, FAB.
]
[Illustration:
FIG. 38.—PIECE OF ASH-BARK, SHOWING MOTHER GALLERIES OF _HYLESINUS
CRENATUS_ ON THE INNER SIDE.
]
_June 25, 1900._
I am very much obliged to you for all the great trouble which
you have been good enough to take about the Ash-bark beetles,
including your letter of the 23rd and the box of specimens
received to-day. Some of the workings are quite certainly of _H.
fraxini_. One bit catches the eye at a glance as showing quite
typical galleries. In the long strip the workings are not so
clearly distinguishable. According to descriptions or comparison
with other specimens they appear to me of both kinds. But I
really cannot think of giving you further trouble. We have all
that is needed to make out a good, sound account, and I hope, if
all be well, to do justice to the subject in my next Annual
Report, and that you will be satisfied with my working up of the
points of the infestation.
With renewed hearty thanks, yours very truly,
ELEANOR A. ORMEROD.
_To A. W. George, Esq., Sedbury, Tidenham, Chepstow, Agent on Sedbury
Estate._
TORRINGTON HOUSE, ST. ALBANS,
_February 17, 1897_.
DEAR SIR,—My work is chiefly on injurious insects, so I am
afraid I am not qualified to give you the exact name of this
curious collection of cement-like pupa-cases. Still I may say
that your description most resembles those of the Mason bee, a
kind of _Osmia_ which constructs cells of a plaster formed of
little morsels of stone, earth, &c., and then fills them with
food and lays an egg on it, walls up the cell, and begins
another. The grub in due course hatches and feeds, and goes
through its changes to the perfect bee—and somehow or other
manages to make its exit. These cells are sometimes made on
walls, in parties of as many as a dozen (as shown in a figure
before me), but as I said, I am not a “specialist” on
_Hymenoptera_ (Bees and Wasps), so I would not like to express a
decided opinion. Your mention of the Roman coin found near the
Severn cliffs is very interesting, for it was quite inexplicable
to my father how it happened that, whilst coins are just the
things often found in such great plenty amongst Roman remains in
the pottery, bones, &c., of which there was such quantity in the
site of the Summer Station of the Augustan Legion from Cærwent
on the Sedbury cliffs, we absolutely did not _have_ a single
coin. Circumstances since we left have made me think that the
word I have underlined may be more correct than that none were
found. On one occasion it chanced I went when the ditch-diggers
were at their dinners, and under a little shelter of turf (which
naturally I inspected) I found a very nice little Samian cup. No
more were reported as found; but after we left I heard of a box
being in one of the lofts over the stables, addressed to myself,
which when opened was found to contain more of these Samian
cups, and also geological specimens from the cliffs. Of course I
wrote down at once, but (perhaps equally of course) by that time
the box had vanished. Your letter of this morning recalled all
this to me, and made me think that very likely the domestic
collector of curiosities who appropriated the Samian cups also
made a little collection of the coins, whose total absence
appeared so surprising. This is a very long story, but I thought
it might be of some interest to you.
I suppose most of our old work-people are gone?
Might I venture to trouble you, in case you should be good
enough some day to find time to write, kindly to let me know
whether my father and mother’s grave (vault) just below the high
bank with the pathway on the top in Tidenham Churchyard (plate
VII.) is in proper repair? If anything is requisite I think you
would likely be so very good as to tell me, and to whom I should
apply to do the work. Trusting you will forgive the intrusion on
your time of such a long letter, I beg to remain, yours truly,
ELEANOR A. ORMEROD.
[Illustration:
PLATE XXV.
RUINS OF CHEPSTOW CASTLE, MONMOUTHSHIRE.
(_p. 16._)
]
_To Edward T. Connold, Esq., F.E.S., Hon. General Secretary, Hastings
and St. Leonards Natural History Society._
TORRINGTON HOUSE, ST. ALBANS,
_July 4, 1900_.
DEAR SIR,—I think that perhaps before this reaches you, you will
have heard from the Rev. E. N. Blomfield that these curiously
formed damsons, of which you have forwarded me such excellent
specimens, owe the galled growth to the attack of a parasite
fungus. They are what you called popularly Bladder plums, or
Pocket plums (fig. 39), and the cause of this extraordinary
growth is the presence of the fungus _Exoascus pruni_. I do not
myself work on Fungi, so I should not have considered myself
qualified to give you trustworthy information, but I see in
Professor Marshall Ward’s good account of this attack, that,
besides reproduction taking place by means of the spores
carrying the disease from tree to tree, he mentions that the
fungus can carry on its existence from year to year by means of
its mycelium in the branches. Consequently much pruning back, as
well as collecting and burning the “pockets,” is needed to
combat the attack to any serviceable extent. I am not troubling
you with details, for you would find them so well entered on in
Ward’s useful little book, of which I gave the name yesterday to
Mr. Blomfield, that I think you would prefer them in his
wording. Hoping I may have assisted you a little in the matter.
[Illustration:
FIG. 39.—POCKET OR BLADDER PLUM INFLATED AND DISTORTED BY THE FUNGOID
ATTACK OF _EXOASCUS PRUNI_ (After Sorauer).
]
_December 19, 1900._
I am greatly obliged to you for the kind thought of sending me
the photo of the Bladder plums. This shows the difference
between the healthy and the diseased fruit so well that if I had
not secured a figure of the diseased growth I think I should
have asked your permission to copy part for my next Annual
Report. This assuredly is not an insect attack. Still, as it may
very often give rise to much perplexity, I thought that (with
due explanation) there could be no objection to including your
good contribution, and I hope that when in due time you receive
your “contributor’s copy” you will not disapprove.
About Dr. Nalepa’s publications; I dare not offer to lend them,
for all I have are copies presented successively during a long
course of years, and if any mishap occurred, I should be in a
difficult position. But if you have not yet applied to them,
Messrs. W. Wesley & Son would be more likely to help you than
anybody I am acquainted with. They would almost certainly be
able to give you the titles of the successive publications and
prices, and also procure for you such as are published. At one
time I worked a great deal on vegetable galls, _Cynips_ galls
chiefly, but _Phytoptus_ galls I have always found so very
troublesome in several points of view that I have never worked
on them more than I can help. Very truly yours,
ELEANOR A. ORMEROD.
_To Messrs. W. J. Coleman & Sons, Fruit, Pea, and Potato Salesmen,
Covent Garden Market._
TORRINGTON HOUSE, ST. ALBANS,
_August 1, 1900_.
DEAR SIRS,—I would very gladly help you about the
moth-caterpillar attack on your potatoes, but I am afraid that
without caterpillar or moth I cannot name it. There are very
many infestations to potato of caterpillars, nearly allied to
what you will, I think, very likely know well as the “Turnip
grub.” These are so numerous that it would be quite hopeless for
me to endeavour to name merely from description and the
chrysalides; and even with the caterpillar it would have been
difficult (though I would with pleasure have tried), on account
of some of these pests greatly resembling each other, and also
some (identical grubs) altering their colours completely as they
moult. I should have been glad to help you, but as these
creatures are now turning to chrysalides the attack is
presumably nearly over for the present.
P.S.—For general use in an attack of this kind the spray that
you have been using, which is very nearly equivalent to the
U.S.A. kerosene emulsion, is probably about as good as you could
try; for I conjecture that you might not like to try
“Paris-green”? Possibly this would not answer, and for various
reasons—it being a ground crop as well as the tuber a food
crop—it might not be desirable; still, I just name it.
_August 4, 1900._
I am obliged by the fresh specimens of caterpillars received
this morning from your agent, Mr. Carswell, and from these and
the moths coming out to-day from the chrysalides previously sent
me, I am able to say that the larvæ are those of the _Plusia
gamma_ moth, popularly known as the Silver Y-moth. I am not
aware of these caterpillars having been recorded as injurious to
potato leafage, excepting in the year 1892, when I had
information of two attacks to this crop, in both instances from
caterpillars migrating from clover. It is too late to-night to
give you a detailed account, but I write now, as you will be
interested to have the identification as soon as possible.
[Illustration:
1, Eggs; 2, caterpillar; 3, chrysalis in cocoon; 4, moth.
FIG. 40.—GAMMA OR SILVER Y-MOTH, _PLUSIA GAMMA_, LINN.
]
_August 5, 1900._
Your potato attack is, as I mentioned last evening, caused by
the caterpillar of the Silver Y-moth, so named from a small
bright mark on the fore-wings, in shape like the English Y or
the Greek _Gamma_. The moth is about half an inch in the spread
of the fore-wings, which have a satiny lustre and are varied
with rich coppery, as well as grey and brown, marks. The hinder
wings are greyish, with a brown border. The caterpillars are
fairly recognisable by being what are called “half-loopers.”
Having only two pairs of sucker feet beneath the body (besides
the customary claw feet) they form a slight arch when they walk.
The attack is occasionally very destructive and is one of those
which we have proof of having been blown to us, in moth
condition, from the Continent; and, from some information which
has come to my hands since I received your letter, I think it is
not at all unlikely such may be the case now, with another kind
of crop. The caterpillars feed on many plants, those of the
cabbage and turnip kind especially; also on _Leguminosæ_, as
peas and beans. Sugar beet they are destructively partial to. I
should not at all think that the attack was likely to recur to
potatoes, or that, as the infestation is now past its
destructive stage, it was worth troubling yourselves about. If
you should desire more about it than I can easily condense into
a moderate letter space, you would find a careful account of the
attack, with a good figure, in my sixteenth Annual Report on
Injurious Insects. Hoping, however, that my few notes may be all
you require, yours truly,
_Eleanor A. Ormerod_.
------------------------------------------------------------------------