Loss of New Growth in Norway Spruce
excerpts from e-mail discussions
compiled by Gerry Hawkes
If you have not already done so, please see what is happening to the Norway spruce by clicking on this link.
E-mail excerpts:
Date: January 30, 2000 11:20 AM
Subject: Norway Spruce
On one of your web pages Gerry Hawkes points out the
"unusual" dropping
of growing tips by Norway Spruce and shows photos and asks
"what is
happening?"
We have a very serious case of the same phenomenon.
Have you learned anything more about the cause or treatment or
prevention?
Thanks.
--Bill
*****
Date: Monday, January 31, 2000 9:07 PM
Subject: Re: Norway Spruce
Dear Bill,
As yet I do not have a good explanation of the dropping of new
growth from
Norway Spruce as shown at http://www.biketrack.com/N_Spruce.htm
although I
strongly suspect the influence of acid deposition and air
pollution on
nutrient uptake.
The damage was probably not caused by squirrels for several
reasons: (1) It
happened too rapidly (2) There was not a single chew mark
found (3) All
the new growth detached precisely at the node where the most
recent year's
growth began.
I have heard that similar loss of growing tips has been observed
in the
Black Forest of Germany. Where are you located?
Best regards,
Gerry Hawkes
Consulting Forester
Woodstock, VT
*****
Date: January 31, 2000 10:33 PM
Subject: Re: Norway Spruce
Dear Gerry--
Thanks you for your response. Our Norway Spruce is a
stand alone mature
tree of at least 80 Ft in height which we have know for 25
years. It has
never in these 25 years dropped tips noticeably
before. The tree is
located in Wayland, Massachusetts. This year it started
dropping tips in
November and by December it had dropped over two hundred 3 to 6
inch tips.
The tip dropping continues and there have probably been 50 more
tips
dropped in January.
A web search has only turned up mention of a "tip
weevil" pest that Norway
Spruce are susceptible to, but nothing more other than that
name. No refs.
None of the "tree info" pages, mostly associated with
agricultural schools,
had anything useful.
My concern is that the tree will die. Do you have any
data on tree
recovery in these cases? Is there a world expert on Norway
Spruce?
Thanks again for your webpage - it was really the only thing out
there on
this.
--Bill
*****
Date: Friday, February 04, 2000 6:27 PM
Subject: Re: Norway Spruce
Dear Bill,
Please excuse the slow response. I have been out of town
for four days.
The information you provide about your own Norway spruce sounds
much like
what I have observed. I have seen no sign of weevils.
I would also like to know the answers to many of the questions
you ask, but
just have not had the time to seek them out. Would you mind
if I forwarded
your e-mail below to an e-mail list of about 900 forestry
experts? There is
a good chance we will get a response that will give us additional
insight.
I can't say for sure if your tree will live or die without seeing
it and
without having observed the trend of needle and tip loss.
Over the past
twenty years I have observed the steady thinning of needles on
the majority
of Norway spruce which has led to much higher levels of tree
death than
should be occurring. This needle thinning still
continues. Dropping of the
tips is a rapid acceleration of the dying process if a tree is
already
losing needles.
As soon as you give me the O.K., I will forward your e-mail to
the
international forestry list.
Best regards,
Gerry Hawkes
Eco Systems, Inc. & Bike Track, Inc.
Woodstock, Vermont
*****
Date: February 14, 2000 2:45 PM
Subject: loss of new growth on Norway Spruce
Dear Gerry,
Without going through the history of "new shoot
loss" as occured in Europe
due to the Impact of air pollution upon the evergreens, and
without
discussing your own observations to the Norway Spruce of your
area, I,
nevertheless, would like to add a few words to this story.
I will, however,
commend you on your dedication to detail in your studies, and it
is for this
reason that I write.
My first knowledge of this "casting of new growth"
is that which occured in
Europe, and the second credible knowledge that I have encountered
is that
which you have so carefully doccumented, and I do applaud your
efforts in
that they make me know that my own observations are also
accurate.
I have read and re-read the various corespondence that you
have shared with
me on this matter, and rather than address any particular peice,
I will
simply tell of my own observations, in short form.
I am here in the Beckley area of Raleigh County, West
Virginia, and as you
are well aware, my observations of the multitude of changes that
are
occuring in all species of trees are are conducted
daily......observations
that take me through a four state area. Let it be noted
that my
observations of the casting of new growth, as is occuring in the
Norway
Spruce, is yet on going, so I will speak only of my immediate
area, which is
studied in detail.
I have spent countless hours in the study of the Norway Spruce
as I simply
had to witness the falling of these shoots as they came to meet
the ground,
and with patience in check, I found this to be no problem at all.
After seeing many of these tips fall to the ground, I began
touching as many
as I could with my finger, and a great many of these also
fell. After this,
I gave several of the limbs a vigorous shake and a great many
more did fall
to the ground. I then picked several branches and shook
them till not one
more tip would fall..........then, I kept very close watch on
these trees
that are growing in various areas of my lawn, or near to my
house. I was
quite amazed at how quickly new tips became ready to fall.
I would simply go again and again from tree to tree and touch as
many tips
as I could and soon, one would tip down 90%.....not quite ready
to fall on
its own. Only a matter of a few hours are needed for this to
happen.
I will close by telling you that no squirrel, mouse, bird, or
any other
creature did play any part in causing these tips to fall as I,
like you, did
use the snow method of observing tracks (of which there were
none) and also
the fact that the trees are too wide spaced to allow
jumping from tree to
tree, and not to be overlooked is the fact that I did remain upon
the scene
that I have no doubts about anything that did occur.
Please allow me to say that before I lay me down to sleep that
night, I
found it necessary to stand before the mirror that I might look
upon the
creature that did cause this ugly event to occur.........and, I
did lay me
down sad.
Keep up the good work ,Gerry Hawkes.
Joe Aliff
*****
Date: Monday, February 14, 2000 4:24 PM
Subject: Re: Loss of new growth on Norway Spruce
Dear Gerry--
Thanks very much for keeping me in the loop on
this. I read with great
interests each comment. It does seem clear now it's not the
squirrels but
perhaps a quite impressive abort mechanism of the tree itself.
--Bill
*****
Date: Monday, February 14, 2000 4:56 PM
Subject: Re: Loss of new growth on Norway Spruce
Bill,
As you can see, the issue is much larger than
"just" the loss of new growth
on Norway Spruce. If you have the opportunity you should
read The Dying of
The Trees by Charles E. Little.
If you have additional, more detailed observations of your Norway
spruce,
please do share them since it may help spur research into the tip
loss
phenomena.
Best regards,
Gerry Hawkes
www.biketrack.com
*****
To: FOREST <FOREST@LISTSERV.FUNET.FI>
Date: Tuesday, February 15, 2000 8:19 AM
Subject: Norway Spruce Tip Loss
Several comments have come in suggesting that
the heavy loss of Norway spruce new growth was probably due to
squirrel damage. My original observations virtually
excluded squirrel damage, but I went out and observed again this
past week. Following these most recent observations I would
have to say that nocturnal or diurnal snipping of the new
growth by
squirrels is an extremely remote possibility for several reasons:
(1) Growing tips were observed at the
moment they detached at the node and
fell to the ground.
(2) It would be extremely difficult for squirrels to get way out
on the
flexible branch tips of Norway spruce and tug on 100's of tips
just enough
to loosen them so they later fell in a steady rain of tips from
the tree on
a calm day.
(3) There were absolutely no signs of any chewing or teeth marks
on the tips
or needles.
(4) This loss of tips has been observed occurring on many
trees
simultaneously (but not the same trees over and over) during the
past 4
years and never has a squirrel or even squirrel tracks been seen,
even when
the tip loss was on isolated trees.
(5) Every tip was separated precisely at the node.
(6) The configuration of Norway spruce branches is such
that once tips are
detached from the node, it is extremely unlikely that they can
come to rest
on a branch rather than tumble to the ground, thus the tips
almost always
reach the ground within a few seconds after they detach.
(7) I have been observing needle loss on Norway spruce very
closely since
the mid-1970's, but did not see this extreme tip loss until
1996. Squirrels
were certainly plentiful prior to 1996.
Just as a note. The dropped tips appear very healthy with
no signs of
browning, weeviling, or needle loss on the tips themselves as you
can see in
the picture at the bottom of the page at
http://www.biketrack.com/N_Spruce.htm . I have seen this abnormal tip
dropping at all times of the year, but it is much easier to
observe soon
after a new snowfall.
What concerns me most is that while I do not see other tree
species
dropping new growth like the Norway spruce, virtually all tree
species are
showing a variety of signs of mild to extreme stress and
accelerating leaf
and needle loss as well as dieback and mortality. Given the
situation, I
would expect that researchers would be eager to study such a
readily
observable and abnormal phenomena as massive tip dropping by
Norway spruce,
yet I know of no such studies underway.
Gerry Hawkes Eco Systems, Inc, Woodstock, Vermont
*****
Date: Thursday, February 17, 2000 11:19 AM
Subject: Re: Norway Spruce Tip Loss
I'd like to offer a possible answer to this question. I
have seen this
"phenomenon" on white spruce, a native species, in
MN. There is was caused
by red squirrels clipping off the branch tips. Little
buggers have very
sharp teeth and thus, don't leave much in the way of chewing
marks.
Just for the record, Norway spruce isn't native to North America,
so if it
disappeared tomorrow it wouldn't be the end of the world.
Regards,
Larry
*****
Date: Thursday, February 17, 2000 11:41 AM
Subject: RE: Norway Spruce Tip Loss
Dear Gerry, A colleague of mine (entomologist) suggested that
there was more
evidence against the effects of squirrels. He would expect that
through
browsing squirrels, the branches would be spread less regular in
the snow.
Now it is an even picture. Squirrels roam around a bit and eat
here and
there (apart from the fact that they do not seem to have eaten
here anyway,
looking at the branches themselves). It is a strange phenomenon.
I do not
know it from Europe in this form, but I do not have a complete
and recent
overview of course. When we see fallen green branches (of e.g.
spruce,
Douglas-fir) it is usually associated with wind, and not
exclusively last
years shoots.
With greetings, Ad Olsthoorn
Silviculture
Alterra, Wageningen, Netherlands
*****
To: FOREST@listserv.funet.fi
<FOREST@listserv.funet.fi>
Date: Saturday, March 04, 2000 1:53 PM
Subject: Red Spruce vs. Norway Spruce tip loss
As the winter's snow melts, the tips of red spruce branches that fell during the winter are being revealed. It is quite obvious that the red spruce tips, which can be found under dispersed groups of trees, were clipped by squirrels. The tip clippings of the red spruce are random in size ranging from part of the current year's growth to two or three year's growth. Almost always the tips are clipped between the nodes and small teeth marks can be seen. Also the fall of tips from the red spruce appears to have been cumulative over the course of a winter rather than a sudden loss.
While it is obvious that squirrels are responsible for the majority of red spruce tip loss that I have observed, it is even more obvious that squirrels are NOT responsible for the heavy tip loss in Norway spruce. (see http://www.biketrack.com/N_Spruce.htm )
The question remains unanswered: WHAT IS HAPPENING TO THE NORWAY SPRUCE?
Best regards,
Gerry Hawkes
Eco Systems, Inc. & Bike Track, Inc.
Woodstock, Vermont
*****
To: FOREST@listserv.funet.fi
<FOREST@listserv.funet.fi>
Date: Friday, March 10, 2000 4:42 AM
Subject: Norway Spruce Tip Loss
In response to my question "What is happening to the Norway spruce?" I received the following response from Joe Aliff in Rock Creek, West Virginia.
Concerning tip loss on the Norway Spruce; I will simply ask that you also think about the white pine needle....how that one half of the needle drops off. I will also ask that you think about the petiole of tree leaves........how that they develop a spot that causes a part of the leaf to fall to the ground.....or that the entire leaf fall to the ground. This same thing happens to the Hemlock........etc. The reasons are well known......ground level ozone and UVB. Ground level ozone is one culprit.....UVB only makes matters worse. To be remembered is the fact that the tree is already stressed by a constant intake of poison that is taken in by way of the roots and leaves......poison that is no less than a herbicide. Add to this, the fact that the veins and arteries of the trees are being plugged by such as calcium and aluminum's that produce strokes.....a portion of the whole quits working.
- Joe Aliff
Best regards,
Gerry Hawkes
Eco Systems, Inc. & Bike Track, Inc.
Woodstock, Vermont
*****
Date: Tuesday, March 14, 2000 8:55 AM
Subject: Concerning the Norway Spruce
As we consider the reasons for the tip loss of the Norway Spruce, should we not also consider the fact that every tree in the forest has, and is, giving up a portion of itself.......lest we see "a link" and not the entire chain? Without doubt, I know that you agree that we should. On that note, I would like to suggest that we give equal attention to the "tip loss" of all trees.......especially in that we consider the dying of the "apical bud", as can be evidenced on nearly every tree and shrub in the forest. This loss of the apical bud causes profound changes to a tree in that the normal growth characteristics are entirely changed. The loss of the apical bud has the exact same effect as would "topping and pruning" that were done by any other manner. What we get is crooked, shorter, trees.....not hardly what we would consider to be trees of high timber quality. While I do agree that the Norway Spruce is the best "study example" of tip loss---in that conditions as are afforded by snow cover allow us to be detectives beyond our abilities----I also think that we need to pay special attention to each shrub and tree that we walk by, for they do "all" carry evidence of tip loss. I make this suggestion to help us understand that unless "squirrels" be as thick as the flying insects of the forest, that we need to look for another explanation for the undeniable damage that surrounds us......no matter where we live upon this globe.
Thank you,
Joe Aliff
*****
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