How do you keep a Japanese black pine healthy? We have six of them,
on the shoreline of a tidal creek off the Rappahannock River, in the
Chesapeake Bay area of Virginia, and although they are supposed to
thrive in a somewhat salty wind, bunches of needles keep turning
brown. This is the second set of grown pines we have planted (the
first was torn up by Hurricane Isabel, but had brown patches before
that). |
Request for Question Clarification by
tlspiegel-ga
on
08 Nov 2004 10:26 PST
Hi maryco,
In order to get a better idea of the problem, would you please clarify
if either of the following descriptions and pictures appear to be what
is wrong with the trees?
http://www.ces.ncsu.edu/depts/pp/notes/Ornamental/odin19/od19.htm
Scroll to the second yellow section where you'll see the words on the left:
Most Species. Needle Cast. Previous years needles turn brown from
tip to base in spring; infected needles shed later in year, leaving
only new growth; most commonly occurs on lower crown.
Then if you scroll to the near the bottom of this page.
You'll see a yellow background and the words: Scots, Japanese black, Austrian.
The disease is called Pine wood nematode. General wilting of needles,
followed by yellowing, browning and finally death of the tree, usually
within 30-90 days after onset of symptoms. The nematodes are spread
from tree to tree by pine sawyers (Monochamus spp.). Confirmed
diagnosis can only be made by removing the nematodes from symptomatic
branches or increment borings from the trunk in the laboratory.
The next yellow background has the words: Primarily longleaf and
Japanese Black... the disease is called Brown spot needle blight.
Symptoms appear as spots that often enlarge to bands that encircle the
needles, causing death of the needle beyond the bands. Spots may
appear at any time of the year, but usually from May to October.
Longleaf seedlings still in the "grass stage" are especially
susceptible.
=========
Thank you,
tlspiegel
|
Clarification of Question by
maryco-ga
on
08 Nov 2004 13:52 PST
Hello tlspiegel, and thanks for your prompt response. We are still
brooding over the answer, and waiting for a better look at our pine
trees in the morning.
Of the three possibilities described, the worst one seems closest.
But what does a nematode look like? Our needles seem to turn yellow
in bunches first, then brown. But there's no wilting, at least none
to the point where needles appear limp, and the damage so far is not
extensive. As we returned home last week after a four-month absence,
we'll have to consult neighbors to try to find out when this began.
We'll be back to you as soon as we have more information, but in the
meantime, a description of nematodes would help.
If this turns out to be more than a $25 question, we'll be glad to up
the bidding for an answer. Thanks, maryco
|
Request for Question Clarification by
tlspiegel-ga
on
08 Nov 2004 14:13 PST
Hi maryco,
Thank you for your reply.
http://www.uvm.edu/~dbergdah/pwn/pwn.html
"... the pinewood nematode (Bursaphelenchus xylophilus ), a
microscopic roundworm that is vectored or carried by pine sawyer
beetles of the genus Monochamus."
Click on link for pine sawyer beetles. Ugly!
*****
http://cipm.ncsu.edu/ent/Southern_Region/RIPM/CHAP4/OPM/chap4.htm
Middle of page on right side: See image - Figure 4-6
Pine wilt symptoms on Scotch pine
Pine Wilt
"Symptoms: Needles rapidly turn reddish brown and individual branches
or the whole tree dies quickly (Figure 4-6). Trees usually die from
midsummer to late fall, especially during periods of water stress. The
trees wilt and die because resins produced in response to infection by
the pine wood nematode clog water-conducting tissues.
Occurrence: In Oklahoma, the disease is most common on Scotch,
Japanese black, and Austrian pines.
Cause: Pine wilt is caused by the pine wood nematode Bursaphelenchus xylophilus.
Conditions Favoring: The pine wood nematode is spread by wood-boring
cerambycid beetles (the pine sawyer and other Monochamus spp.) which
acquire the nematode during development in diseased trees, and then
introduce the nematode to healthy trees by feeding or laying eggs on
them. The pine sawyer is the most common beetle vector in Oklahoma.
The beetles are attracted to stressed trees.
Management: There is no direct control for the pine wood nematode.
Dead or dying trees should be removed and disposed of to eliminate
breeding habitat for the beetles and to kill its larvae and pupae.
Since stressed plants attract the beetles, unnecessary stress should
be prevented by managing known pathogens and insects and utilizing
good cultural practices. Control of the beetle vectors with
insecticides has not been effective. More resistant pine species (such
as loblolly, Virginia, and slash pine) should be planted."
=========
Lastly, would you please clarify what you mean by "Of the three
possibilities described, the worst one seems closest."
I'm not clear on what you're referring to, so point that out to me if
you can, and I'll try to find more information.
Thanks again,
tlspiegel
|
Clarification of Question by
maryco-ga
on
09 Nov 2004 06:14 PST
"The worst one" I meant was the one with the nematodes! Though from
your latest elaboration, seems less likely. We are heading out today
with magnifying glasses.
|
Request for Question Clarification by
tlspiegel-ga
on
09 Nov 2004 07:30 PST
Hi maryco,
Thank you for your clarification. Nematodes is what I thought you
were referring to... ugly stuff, eh?
Let me know what you find after you take a better look-see with your
magnifying glass. By the way, one thing you might want to do is clip
off a portion of the needles where you see the damage and take it to a
local nursery for them to correctly identify what's what. If you do
this, I'd place the amount inside of a plastic bag. You also might
look for infestation while poking around with the magnifying glass...
bugs, insects, beetles, etc.
One way to identify infestation is take a plain white piece of paper
and hold it under one of the needle segments. Wait about 2 minutes
and then see if anything is crawling on the paper. Black, red dots.
I had to do this with some arborvitae when they started having a lot
of needle browning.
Best regards,
tlspiegel
|
Clarification of Question by
maryco-ga
on
10 Nov 2004 11:09 PST
Hi, tlspiegel,
My husband has returned from the Japanese pines with magnifying glass,
plastic bag, needles, sheet of white paper, and a worried expression.
"I think we've got something here," he said, "but I can't see what."
We will be within reach of a nursery over the weekend, and will take
our evidence there as you suggested (tightly sealed).
We will be back in touch early next week.
Allbest, maryco
|
Clarification of Question by
maryco-ga
on
15 Nov 2004 12:42 PST
Dear Tlspiegel,
We have now been to a nursery, which was not able to help (and seemed,
understandably, to shrink from doing so), but were directed to the
local Agricultural Extension Agent, which sounds good. In the
meantime the moving spot in our first sample seems to have stopped
moving. My husband is trying to capture another. We will keep you
abreast.
Allbest, maryco
|
Request for Question Clarification by
tlspiegel-ga
on
15 Nov 2004 13:54 PST
Hi maryco,
Thank you for the update. Please do keep me informed as to what you find out.
Best regards,
tlspiegel
|
Clarification of Question by
maryco-ga
on
24 Nov 2004 13:52 PST
Dear tlspiegel,
We have hit a plateau in our investigations: Nothing seems to be
moving! That being the case, and given the wealth of material and
suggestions you have already given us - much of which may yet prove to
be useful - please post this question as answered and let us add a tip
(inadequate for such priceless help, but nevertheless a gesture).
We hope to encounter you again. In the meantime, Happy Thanksgiving!
|
Hi maryco,
Well, I'm truly sorry nothing in our communications with each other
has proven to be the problem, and we've been unable to find a solution
or a cure. I know how frustrating it is to see something happening to
a tree(s) right before your very eyes and no one can determine what's
what.
Being this is the second set of trees that have mysteriously had
bunches of needles turning brown it appears that any number of things
could be the reason and cause. Only a few of them might be:
Either the ground where they've been planted doesn't contain optimum
conditions, or the nursery where they were purchased had some problems
with their crop (hard to detertermine that!) or the area where they
were actually grown from babies had something awry, or something in
the area is providing less than ideal circumstances. All this is
speculation and 'what iffing' and I don't like to 'what if'.
So, with that said, because you requested me to post my findings in
the answer box I will provide my findings.
==========
In order to get a better idea of the problem, would you please clarify
if either of the following descriptions and pictures appear to be what
is wrong with the trees?
http://www.ces.ncsu.edu/depts/pp/notes/Ornamental/odin19/od19.htm
Scroll to the second yellow section where you'll see the words on the left:
Most Species. Needle Cast. Previous years needles turn brown from
tip to base in spring; infected needles shed later in year, leaving
only new growth; most commonly occurs on lower crown.
Then if you scroll to the near the bottom of this page.
You'll see a yellow background and the words: Scots, Japanese black, Austrian.
The disease is called Pine wood nematode. General wilting of needles,
followed by yellowing, browning and finally death of the tree, usually
within 30-90 days after onset of symptoms. The nematodes are spread
from tree to tree by pine sawyers (Monochamus spp.). Confirmed
diagnosis can only be made by removing the nematodes from symptomatic
branches or increment borings from the trunk in the laboratory.
The next yellow background has the words: Primarily longleaf and
Japanese Black... the disease is called Brown spot needle blight.
Symptoms appear as spots that often enlarge to bands that encircle the
needles, causing death of the needle beyond the bands. Spots may
appear at any time of the year, but usually from May to October.
Longleaf seedlings still in the "grass stage" are especially
susceptible.
=========
http://www.uvm.edu/~dbergdah/pwn/pwn.html
"... the pinewood nematode (Bursaphelenchus xylophilus ), a
microscopic roundworm that is vectored or carried by pine sawyer
beetles of the genus Monochamus."
Click on link for pine sawyer beetles. Ugly!
*****
http://cipm.ncsu.edu/ent/Southern_Region/RIPM/CHAP4/OPM/chap4.htm
Middle of page on right side: See image - Figure 4-6
Pine wilt symptoms on Scotch pine
Pine Wilt
"Symptoms: Needles rapidly turn reddish brown and individual branches
or the whole tree dies quickly (Figure 4-6). Trees usually die from
midsummer to late fall, especially during periods of water stress. The
trees wilt and die because resins produced in response to infection by
the pine wood nematode clog water-conducting tissues.
Occurrence: In Oklahoma, the disease is most common on Scotch,
Japanese black, and Austrian pines.
Cause: Pine wilt is caused by the pine wood nematode Bursaphelenchus xylophilus.
Conditions Favoring: The pine wood nematode is spread by wood-boring
cerambycid beetles (the pine sawyer and other Monochamus spp.) which
acquire the nematode during development in diseased trees, and then
introduce the nematode to healthy trees by feeding or laying eggs on
them. The pine sawyer is the most common beetle vector in Oklahoma.
The beetles are attracted to stressed trees.
Management: There is no direct control for the pine wood nematode.
Dead or dying trees should be removed and disposed of to eliminate
breeding habitat for the beetles and to kill its larvae and pupae.
Since stressed plants attract the beetles, unnecessary stress should
be prevented by managing known pathogens and insects and utilizing
good cultural practices. Control of the beetle vectors with
insecticides has not been effective. More resistant pine species (such
as loblolly, Virginia, and slash pine) should be planted."
=========
Nematodes is what I thought you were referring to... ugly stuff, eh?
Let me know what you find after you take a better look-see with your
magnifying glass. By the way, one thing you might want to do is clip
off a portion of the needles where you see the damage and take it to a
local nursery for them to correctly identify what's what. If you do
this, I'd place the amount inside of a plastic bag. You also might
look for infestation while poking around with the magnifying glass...
bugs, insects, beetles, etc.
One way to identify infestation is take a plain white piece of paper
and hold it under one of the needle segments. Wait about 2 minutes
and then see if anything is crawling on the paper. Black, red dots.
I had to do this with some arborvitae when they started having a lot
of needle browning.
=========
Again, I'm very sorry we haven't been able to solve the problem.
I do wish you and your family a very Happy Thanksgiving and a Wonder
Holiday Season.
May you be safe and healthy!
Best regards,
tlspiegel |
