I need some help understanding and identifying the kind of borers I
have. Because early on (years ago) Baldo Villegas posted that
generally these creatures are not generally harmful, I have paid
little attention to mine, assuming they would just use the last
half-inch of the cut canes for a place to lay their eggs.

But I am seeing a LOT of borer holes--big wide ones in the ends of cut
canes, almost exclusively on my grafted roses. (Perhaps my ownroots
are too young to have thick enough canes for their liking?)

And recently there was discussion on Gardenweb about a kind of borer
that is not harmless, but bores all the way to the bud union and kills
the plant. How can I tell which kind I have and if I can't does it
mean I have to seal all the holes?

Shiva,

An image-google for "rose borer" wasn't all that successful, but it did lead
me to "rose stem borer" to "rose stem girdler" Agrilus aurichalceus. Take a
look at this website, it might help you ID your nasty critters:
http://www.forestryimages.org/browse...b=4251&start=1

You may be right about borers preferring canes that are wide enough for
their larvae(?), but I'm not sure about sealing off the holes -- how would
you know that there were no larvae in the cane when you sealed it?

Anne Lurie
Raleigh, NC


"Shiva" wrote in message
s.com...
I need some help understanding and identifying the kind of borers I
have. Because early on (years ago) Baldo Villegas posted that
generally these creatures are not generally harmful, I have paid
little attention to mine, assuming they would just use the last
half-inch of the cut canes for a place to lay their eggs.

But I am seeing a LOT of borer holes--big wide ones in the ends of cut
canes, almost exclusively on my grafted roses. (Perhaps my ownroots
are too young to have thick enough canes for their liking?)

And recently there was discussion on Gardenweb about a kind of borer
that is not harmless, but bores all the way to the bud union and kills
the plant. How can I tell which kind I have and if I can't does it
mean I have to seal all the holes?

An addendum to my own previous answer to Shiva:

I belatedly recognized the meaning of "Biological Control Agents of
Multiflora Rose, Rosa multiflora Thunbergh" at
http://www.wvu.edu/~agexten/ipm/weeds/multiflor.htm -- he's not talking
about controlling pests of Multiflora Rose, he's talking about controlling
Multiflora Rose by using biological controls, one of which is the rose stem
girdler, Agrilus aurichalceus.

I think the above was written by the same man who took the pictures at
http://www.forestryimages.org/browse...=4251&start=1, which I
previously posted in the hopes that Shiva might be able to ID her rose
borers.

Having proved once again that "a little learning is a dangerous thing," I
think it's time for something "new & different" (to misquote Monty
ython -- in my case, it's different, but not so new: WordRacer -- if any
of you happen to be fellow aficionados, look me up, you'll know me when you
see me!)

Anne Lurie
Raleigh, NC


"Shiva" wrote in message
s.com...
I need some help understanding and identifying the kind of borers I
have. Because early on (years ago) Baldo Villegas posted that
generally these creatures are not generally harmful, I have paid
little attention to mine, assuming they would just use the last
half-inch of the cut canes for a place to lay their eggs.

But I am seeing a LOT of borer holes--big wide ones in the ends of cut
canes, almost exclusively on my grafted roses. (Perhaps my ownroots
are too young to have thick enough canes for their liking?)

And recently there was discussion on Gardenweb about a kind of borer
that is not harmless, but bores all the way to the bud union and kills
the plant. How can I tell which kind I have and if I can't does it
mean I have to seal all the holes?

I dont know the answer but I cut a huge cane off my 10 year old rose bush to
try and root it, and a couple days later I noticed a hole in the top, so I
cut off a half inch, and it was still going deeper, I kept cutting off half
inches until i found the ugly bug about 9 inches into the cane. It was
black with white stripes if memory serves me correctly.


"Shiva" wrote in message
s.com...
I need some help understanding and identifying the kind of borers I
have. Because early on (years ago) Baldo Villegas posted that
generally these creatures are not generally harmful, I have paid
little attention to mine, assuming they would just use the last
half-inch of the cut canes for a place to lay their eggs.

But I am seeing a LOT of borer holes--big wide ones in the ends of cut
canes, almost exclusively on my grafted roses. (Perhaps my ownroots
are too young to have thick enough canes for their liking?)

And recently there was discussion on Gardenweb about a kind of borer
that is not harmless, but bores all the way to the bud union and kills
the plant. How can I tell which kind I have and if I can't does it
mean I have to seal all the holes?

On Sun, 03 Aug 2003 21:33:39 GMT, "Anne Lurie"
wrote:

Anne,

The situation is a "chicken and egg" sort of thing. The worst borer
damage is on the roses that died from canker. But does that mean the
borers contributed to the cause of death, or that they moved in as the
canes died of canker? I think it is the latter, but wanted to be sure.

I finally have the heart to resume my regular preventive Orthenex
spraying, and this stuff apparently does not touch borers, as I have
always had them. If the problem IS part borer damage, I want to treat
it. I have lost enough roses this year, and want to start off right
for next year. Everybody has new growth and I have cleaned up the bs
pretty well, so the time is right.

Cane borers cause damage to the cane regardless of the species of the
critter. Many will carry disease into the cane that will cause further
damage to the plant. The bored cane will normally die back, the rate
depends on the bore damage and what if any fungal disease was carried into
the bore hole. If the damage is sufficient it can potentialy kill the
plant.

Many people 'seal' the canes immediately after they are cut. This tactic
usually doesn't work well because the cut will ooze for a day or so and
prevents most of the sealant from adhering to the end of the cane. A
better, albiet more labor intensive approach is to wait at least 24 hours to
allow the cut to 'dry' and then apply a sealant. This obviously leaves the
freshly cut cane exposed for a period and also requires a second pass
through the garden trying to find all the fresh cuts.

Borers are just one of the nusances we have to put up with and find an
approach that works for each individual gardener.

Unfortunately there is no magic bullet.

Tim

In article , Tim Tompkins
wrote:

Cane borers cause damage to the cane regardless of the species of the
critter. Many will carry disease into the cane that will cause further
damage to the plant. The bored cane will normally die back, the rate
depends on the bore damage and what if any fungal disease was carried into
the bore hole. If the damage is sufficient it can potentialy kill the
plant.

Many people 'seal' the canes immediately after they are cut. This tactic
usually doesn't work well because the cut will ooze for a day or so and
prevents most of the sealant from adhering to the end of the cane. A
better, albiet more labor intensive approach is to wait at least 24 hours to
allow the cut to 'dry' and then apply a sealant. This obviously leaves the
freshly cut cane exposed for a period and also requires a second pass
through the garden trying to find all the fresh cuts.

Borers are just one of the nusances we have to put up with and find an
approach that works for each individual gardener.

Unfortunately there is no magic bullet.

My take on cane borers is different. I don't see serious damage, but
then I don't see the holes going down more that about 6 inches, either,
and most go down 3 inches. They tend to favor larger, less viable canes
anyway, and I'm happy to prune them off once a year. It is possible
that there a regional differences in the critters that do this work.

GamePlayer No. 1058 wrote:

I dont know the answer but I cut a huge cane off my 10 year old rose bush to
try and root it, and a couple days later I noticed a hole in the top, so I
cut off a half inch, and it was still going deeper, I kept cutting off half
inches until i found the ugly bug about 9 inches into the cane. It was
black with white stripes if memory serves me correctly.

Thanks, GP. I have known since the first hole I saw in the end of a cane that I ought
to cut down and find the larva, but this just grosses me out! I'm sure it is
why I have so many borers, right, since I never disturb them. Old Baldo (the Bugman)
would probably say I need to identify what kind of borer it is first, so I need to
do this. Truth is, chemical warfare I can deal with, squishing stuff I just can't.
Maybe if I get them all out of the canes they will just die of exposure. (The rule
in this house is, if it is more than 1/2 inch long and can survive the cats, it
gets to live.) I'll try this weekend.







"Shiva" wrote in message
s.com...
I need some help understanding and identifying the kind of borers I
have. Because early on (years ago) Baldo Villegas posted that
generally these creatures are not generally harmful, I have paid
little attention to mine, assuming they would just use the last
half-inch of the cut canes for a place to lay their eggs.

But I am seeing a LOT of borer holes--big wide ones in the ends of cut
canes, almost exclusively on my grafted roses. (Perhaps my ownroots
are too young to have thick enough canes for their liking?)

And recently there was discussion on Gardenweb about a kind of borer
that is not harmless, but bores all the way to the bud union and kills
the plant. How can I tell which kind I have and if I can't does it
mean I have to seal all the holes?