We have a red oak (Quercus rubra) in our garden, it's now about 25 feet
tall and is in the middle of the lawn.
Every year we've had the same thing happen, it's been absolutely covered
in wasps. They are attracted by the honey dew left by presumably the
aphids which are higher up the tree.
When I say covered, I actually mean that there are clouds of wasps
especially if you disturb the tree, hundreds fly about. (The leaves are
about four times larger than ordinary oak trees.)

This wouldn't be so bad, further away down the bottom of the garden or
if I could spray the tree with systemic insecticide which I have done
every year up till now, though I have been loathe to kill other insects.

However it is now getting too big too spray and in late July and August
we have to close the Patio doors and windows on the garden side at night
to stop stray wasps coming in, attracted to the light. We can have up to
30 wasps crawling up the kitchen window so it is a problem. They don't
bother us in the daytime.

I didn't think wasps flew at night anyway.

Thought that having the tree properly pruned last year would do the
trick but it hasn't and there doesn't seem to be the same amount of
wasps on ordinary oak trees.


If we can't find a solution we may have to cut the tree down which would
be awful as it's such a lovely tree in spring and autumn.


Would hosing the lower leaves wash off the secretions? The recent
thunder and lightning didn't seem to have much effect.


Janet
--
Janet Tweedy
Dalmatian Telegraph
http://www.lancedal.demon.co.uk

On Mon, 9 Aug 2004 11:27:44 +0100, Janet Tweedy wrote:

a red oak (Quercus rubra) [is] absolutely covered
in wasps. They are attracted by the honey dew left by presumably the
aphids which are higher up the tree.

Any evidence of ants farming the aphids? Take a hard look at the
trunk and if you see ants scurrying up and down, consider that
sufficient evidence.

If ants are involved, then if you can keep them out of the crown
of the tree the aphid problem should decline and fall. Some kind
of barrier around the trunk would be called for. The sticky bands
used for wintermoth control will work, but if you can get Sevin
(carbaryl) and spray a band, say, 18" wide around the trunk and
renew it every two or three weeks, that will suffice.

Ants are loath to cross a band of sevin -- they taste it with
their feet -- and if they do, they die.


If ants aren't involved, then painting the trunk with Cygon
(again, if you can still get it) might control the aphids.


Unfortunately, effective special-purpose insecticides such as
Sevin and Cygon are nearly impossible to obtain any more. The
greens have completely driven them off the market, and the
pyrethrins that are left simply won't work in the same way.


--
Rodger Whitlock
Victoria, British Columbia, Canada
[change "atlantic" to "pacific" and
"invalid" to "net" to reply by email]

In article ,
Rodger Whitlock wrote:
On Mon, 9 Aug 2004 11:27:44 +0100, Janet Tweedy wrote:

a red oak (Quercus rubra) [is] absolutely covered
in wasps. They are attracted by the honey dew left by presumably the
aphids which are higher up the tree.

Any evidence of ants farming the aphids? Take a hard look at the
trunk and if you see ants scurrying up and down, consider that
sufficient evidence.

As Blair said to Bush.

If ants are involved, then if you can keep them out of the crown
of the tree the aphid problem should decline and fall. Some kind
of barrier around the trunk would be called for. The sticky bands
used for wintermoth control will work, but if you can get Sevin
(carbaryl) and spray a band, say, 18" wide around the trunk and
renew it every two or three weeks, that will suffice.

Nonsense.

There isn't a scrap of evidence in favour of the theory that
discouraging ants reduces aphids (in the UK), and a hell of a lot
of evidence that it doesn't usually make the slightest difference.
The ants merely follow the aphids, and are irrelevant.

If ants aren't involved, then painting the trunk with Cygon
(again, if you can still get it) might control the aphids.

Good God, why?

Almost all of the aphids in the UK spread by means of flying adults,
and then breed explosively on their target. Some other insects do
overwinter in the soil and climb up, but as far as I know no aphid
does.


Regards,
Nick Maclaren.

In article , Rodger Whitlock
writes

Any evidence of ants farming the aphids? Take a hard look at the
trunk and if you see ants scurrying up and down, consider that
sufficient evidence.

Well if I get a chance to stand under the tree with wasps flying about
I'll certainly look! We have a wasp man coming this afternoon if it
doesn't rain, to eliminate two nets on the front of the house.
That may have some effect also.



If ants are involved, then if you can keep them out of the crown
of the tree the aphid problem should decline and fall. Some kind
of barrier around the trunk would be called for. The sticky bands
used for wintermoth control will work, but if you can get Sevin
(carbaryl) and spray a band, say, 18" wide around the trunk and
renew it every two or three weeks, that will suffice.

Ants are loath to cross a band of sevin -- they taste it with
their feet -- and if they do, they die.


Right, I'll go and see if I can buy the stuff, never heard of it till
you said Rodger.

If ants aren't involved, then painting the trunk with Cygon
(again, if you can still get it) might control the aphids.


Unfortunately, effective special-purpose insecticides such as
Sevin and Cygon are nearly impossible to obtain any more. The
greens have completely driven them off the market, and the
pyrethrins that are left simply won't work in the same way.


Are they systemic then? I thought systemic needed to go onto leaves so
that the liquid went onto the surfaces that would absorb the chemicals
and take it into the sap. Does the trunk of a tree absorb stuff?

janet
--
Janet Tweedy
Dalmatian Telegraph
http://www.lancedal.demon.co.uk

On 9 Aug 2004 18:34:45 GMT, Nick Maclaren wrote:

In article ,
Rodger Whitlock wrote:

If ants are involved, then if you can keep them out of the crown
of the tree the aphid problem should decline and fall...

Nonsense.

Ah, the sweet voice of clarity, enunciating Truth via a well
chosen bon mot.

One learns something new every day.

But let me ask: why, then, do so many gardening books yap about
ants "farming" aphids, even to the point of carting them around
to greener pastures?

Are these descriptions mere N-th generation plagiarisms from an
original description itself based on careless observation?

Or am I just confused? If confusion's your conclusion, please
don't try to take advantage of my weakened state and sell me any
bridges; I just bought the Golden Gate Bridge yesterday and
that's enough for one household.


--
Rodger Whitlock
Victoria, British Columbia, Canada
[change "atlantic" to "pacific" and
"invalid" to "net" to reply by email]

In article ,
Rodger Whitlock wrote:
On 9 Aug 2004 18:34:45 GMT, Nick Maclaren wrote:

In article ,
Rodger Whitlock wrote:

If ants are involved, then if you can keep them out of the crown
of the tree the aphid problem should decline and fall...

Nonsense.

Ah, the sweet voice of clarity, enunciating Truth via a well
chosen bon mot.

One learns something new every day.

True.

But let me ask: why, then, do so many gardening books yap about
ants "farming" aphids, even to the point of carting them around
to greener pastures?

That's a damn good question, and one to which I am not certain of
the answer.

Are these descriptions mere N-th generation plagiarisms from an
original description itself based on careless observation?

In most cases, yes.

Or am I just confused? If confusion's your conclusion, please
don't try to take advantage of my weakened state and sell me any
bridges; I just bought the Golden Gate Bridge yesterday and
that's enough for one household.

I shall try not to sell you any of Cambridge's bridges. The situation
is roughly as follows:

Some ants are known to farm aphids, but all that are definitely known
to do so are tropical.

In the UK, some reliable observers have seen ants move aphids, but it
is unknown whether that was to move them to new pastures or to the
dinner table.

In the UK, some reliable observers have seen ants fighting predators
(e.g. ladybird larvae), but it is unknown whether the ants were
defending the aphids or themselves.

I have investigated the correlation between ant presence and aphid
infestation in my garden and elsewhere and, in the cases I have seen,
none were compatible with the hypotheses that ants spread aphids nor
that they enhance an infestation.

Nobody seems ever to have done an experiment seeing whether reducing
the ant population causes a reduction in the aphids in the UK.

No known entomologist believes that reducing the ant population will
cause a reduction in the aphids in the UK.


Regards,
Nick Maclaren.

"Rodger Whitlock" wrote in message
...
On 9 Aug 2004 18:34:45 GMT, Nick Maclaren wrote:

In article ,
Rodger Whitlock wrote:

If ants are involved, then if you can keep them out of the crown
of the tree the aphid problem should decline and fall...

Nonsense.

Ah, the sweet voice of clarity, enunciating Truth via a well
chosen bon mot.

One learns something new every day.

But let me ask: why, then, do so many gardening books yap about
ants "farming" aphids, even to the point of carting them around
to greener pastures?

Are these descriptions mere N-th generation plagiarisms from an
original description itself based on careless observation?

Or am I just confused? If confusion's your conclusion, please
don't try to take advantage of my weakened state and sell me any
bridges; I just bought the Golden Gate Bridge yesterday and
that's enough for one household.


Rodger, I have a strong feeling that you should reread, slowly, the
post to which you replied here.

Franz

On 10 Aug 2004 20:44:58 GMT, (Nick Maclaren) wrote:

snip

I have investigated the correlation between ant presence and aphid
infestation in my garden and elsewhere and, in the cases I have seen,
none were compatible with the hypotheses that ants spread aphids nor
that they enhance an infestation.

With all due respect, I think the use of the word 'investigated' is
perhaps a tad over-enthusiastic... I recall that there were at least a
couple of very significant factors that went unobserved in your study
( the most notable being, in the case of ants, no night-time study ).

Nobody seems ever to have done an experiment seeing whether reducing
the ant population causes a reduction in the aphids in the UK.

Some empirical evidence here - my beans this year were heavily
infested with aphids early on in the season, and I noticed no ants at
all on the plants.
A little later in the season and the aphid population declined
somewhat - and I still haven't seen an ant on the beans yet, even at
night during my slug patrol.
Neither have I seen any other predators...the aphids just 'upped and
went' ( unless the wasps are taking them ).
In fact, I've seen remarkably few predators at work this year.

No known entomologist believes that reducing the ant population will
cause a reduction in the aphids in the UK.

It doesn't seem that likely...and besides, it might mean far worse
problems anyway.

Regards,



--
Stephen Howard - Woodwind repairs & period restorations
http://www.shwoodwind.co.uk
Emails to: showard{who is at}shwoodwind{dot}co{dot}uk

In article ,
Stephen Howard writes:
| On 10 Aug 2004 20:44:58 GMT, (Nick Maclaren) wrote:
|
| I have investigated the correlation between ant presence and aphid
| infestation in my garden and elsewhere and, in the cases I have seen,
| none were compatible with the hypotheses that ants spread aphids nor
| that they enhance an infestation.
|
| With all due respect, I think the use of the word 'investigated' is
| perhaps a tad over-enthusiastic... I recall that there were at least a
| couple of very significant factors that went unobserved in your study
| ( the most notable being, in the case of ants, no night-time study ).

No, you are mistaken.

While that is true, (a) the ants in the relevant location were all
diurnal (from separate observation) and (b) it does not affect my
investigations of patterns of infestation (checking on whether ants
spread aphids).

In particular, the latter is the aspect that I have observed fairly
widely, largely because it can be checked by a single observation
of the pattern of the aphid infestations.


Regards,
Nick Maclaren.

On 11 Aug 2004 09:24:07 GMT, (Nick Maclaren) wrote:


In article ,
Stephen Howard writes:
| On 10 Aug 2004 20:44:58 GMT, (Nick Maclaren) wrote:
|
| I have investigated the correlation between ant presence and aphid
| infestation in my garden and elsewhere and, in the cases I have seen,
| none were compatible with the hypotheses that ants spread aphids nor
| that they enhance an infestation.
|
| With all due respect, I think the use of the word 'investigated' is
| perhaps a tad over-enthusiastic... I recall that there were at least a
| couple of very significant factors that went unobserved in your study
| ( the most notable being, in the case of ants, no night-time study ).

No, you are mistaken.

No, I'm not. We discussed this some time ago and I specifically asked
if you had observed ant movement and behaviour at night. You said no,
and admitted it was a fair point. It still is.
I feel it's important to lay that caveat against any conclusions you
may have drawn from your studies.

While that is true, (a) the ants in the relevant location were all
diurnal (from separate observation) and (b) it does not affect my
investigations of patterns of infestation (checking on whether ants
spread aphids).

The former precludes the latter, surely.
Ants are highly active at night - who knows what they might have been
up to in the wee small hours?

Regards,



--
Stephen Howard - Woodwind repairs & period restorations
www.shwoodwind.co.uk
Emails to: showard{whoisat}shwoodwind{dot}co{dot}uk

In article ,
Stephen Howard writes:
|
| No, I'm not. We discussed this some time ago and I specifically asked
| if you had observed ant movement and behaviour at night. You said no,
| and admitted it was a fair point. It still is.
| I feel it's important to lay that caveat against any conclusions you
| may have drawn from your studies.

For heaven's sake! You clearly don't understand the investigations
that I performed. With one of the two, it would be relevant, were
the ants in my garden active at night (they aren't, at least not
much). With the other, IT IS COMPLETELY IRRELEVANT.

| While that is true, (a) the ants in the relevant location were all
| diurnal (from separate observation) and (b) it does not affect my
| investigations of patterns of infestation (checking on whether ants
| spread aphids).
|
| The former precludes the latter, surely.
| Ants are highly active at night - who knows what they might have been
| up to in the wee small hours?

That has PRECISELY NOTHING to do with the latter point. As I have
pointed out several times, my pattern of infestation investigations
are as relevant to whether ants are active during the day, at night
or only between 23 and 54 minutes past the hour.

And please do try to read before posting nonsense. AS I SAID, I
have investigated the nocturnal ant activity in my garden, and it
is minimal compared to the diurnal. BUT THE INVESTIGATION TO WHICH
THAT MIGHT BE RELEVANT IS NOT THE SAME ONE AS THE ABOVE.

To repeat: I performed MORE THAN ONE investigation, and they used
different methodologies.


Regards,
Nick Maclaren.

On 11 Aug 2004 10:48:19 GMT, (Nick Maclaren) wrote:


In article ,
Stephen Howard writes:
|
| No, I'm not. We discussed this some time ago and I specifically asked
| if you had observed ant movement and behaviour at night. You said no,
| and admitted it was a fair point. It still is.
| I feel it's important to lay that caveat against any conclusions you
| may have drawn from your studies.

For heaven's sake! You clearly don't understand the investigations
that I performed. With one of the two, it would be relevant, were
the ants in my garden active at night (they aren't, at least not
much). With the other, IT IS COMPLETELY IRRELEVANT.

I'm sorry - when did you conduct this other investigation? I've not
seen a further post from you about this since your original one last
year. I must have missed it - please post a reference to it.

| While that is true, (a) the ants in the relevant location were all
| diurnal (from separate observation) and (b) it does not affect my
| investigations of patterns of infestation (checking on whether ants
| spread aphids).
|
| The former precludes the latter, surely.
| Ants are highly active at night - who knows what they might have been
| up to in the wee small hours?

That has PRECISELY NOTHING to do with the latter point. As I have
pointed out several times, my pattern of infestation investigations
are as relevant to whether ants are active during the day, at night
or only between 23 and 54 minutes past the hour.

And please do try to read before posting nonsense. AS I SAID, I
have investigated the nocturnal ant activity in my garden, and it
is minimal compared to the diurnal. BUT THE INVESTIGATION TO WHICH
THAT MIGHT BE RELEVANT IS NOT THE SAME ONE AS THE ABOVE.

How can it not be relevant?
Please take me through this slowly again...
The investigation was whether ants spread aphids, as in '(b)', yes?
In carrying out this investigation you made no nocturnal observations
( unless you've repeated the investigation since )?
If you draw any conclusions from these observations without
correlating ant behaviour, all you will have done is observed aphids -
yes?
From your observations you're convinced that any nocturnal activity by
the ants is insignificant in respect of the study?
Did your other studies make any discrimination between species?

I'm as interested in the subject as you apparently are - so there's no
need for you to feel defensive. Just say so if you're not prepared to
take questions from the floor.

To repeat: I performed MORE THAN ONE investigation, and they used
different methodologies.

Marvelous, I look forward to reading about the others. Pop it on a
fresh thread if needs be.

Regards,



--
Stephen Howard - Woodwind repairs & period restorations
www.shwoodwind.co.uk
Emails to: showard{whoisat}shwoodwind{dot}co{dot}uk

In article ,
Stephen Howard writes:
|
| I'm sorry - when did you conduct this other investigation? I've not
| seen a further post from you about this since your original one last
| year. I must have missed it - please post a reference to it.

I described it then, and referred to it this time.

The pattern of aphid infestations will be different, depending
on whether the aphids are spread from plant to plant by rain,
flying adults or ants. I have overserved the first two many times
and in many places, and have NEVER seen patterns compatible with
the last hypothesis.

In particular, because it is hard to tell transport by ants from
mobile juveniles, it indicates that most UK aphids of the types
that annoy gardeners most are not very mobile (as all the books
say). They are thus very different from mealybugs.

| How can it not be relevant?
| Please take me through this slowly again...
| The investigation was whether ants spread aphids, as in '(b)', yes?
| In carrying out this investigation you made no nocturnal observations
| ( unless you've repeated the investigation since )?

No. I have in SOME cases looked for nocturnal activity and not
found it. In particular, the common ants in my garden are fairly
strongly diurnal. I did, after your posting, check up and saw
no ants on aphids (or much elsewhere) at night.

Many ants in warmer climates are nocturnal, but the more common UK
ones seem to be diurnal. This probably has something to do with
temperatures, as they are also more active on warm days than on
cold ones.

| If you draw any conclusions from these observations without
| correlating ant behaviour, all you will have done is observed aphids -
| yes?

Yes. I have, however, also looked for correlations, but not in
this case.

| From your observations you're convinced that any nocturnal activity by
| the ants is insignificant in respect of the study?

No. From the nature of the study. And "orthogonal" not
"insignificant".

| Did your other studies make any discrimination between species?

Of ants or aphids? Yes. In particular, I was looking primarily
at black bean and brassica aphids, but looked at any infestations
that were dense enough and on regular enough plants to analyse
patterns.


Regards,
Nick Maclaren.

On 11 Aug 2004 12:51:09 GMT, (Nick Maclaren) wrote:


In article ,
Stephen Howard writes:
|
| I'm sorry - when did you conduct this other investigation? I've not
| seen a further post from you about this since your original one last
| year. I must have missed it - please post a reference to it.

I described it then, and referred to it this time.

The pattern of aphid infestations will be different, depending
on whether the aphids are spread from plant to plant by rain,
flying adults or ants. I have overserved the first two many times
and in many places, and have NEVER seen patterns compatible with
the last hypothesis.

In particular, because it is hard to tell transport by ants from
mobile juveniles, it indicates that most UK aphids of the types
that annoy gardeners most are not very mobile (as all the books
say). They are thus very different from mealybugs.

| How can it not be relevant?
| Please take me through this slowly again...
| The investigation was whether ants spread aphids, as in '(b)', yes?
| In carrying out this investigation you made no nocturnal observations
| ( unless you've repeated the investigation since )?

No. I have in SOME cases looked for nocturnal activity and not
found it. In particular, the common ants in my garden are fairly
strongly diurnal. I did, after your posting, check up and saw
no ants on aphids (or much elsewhere) at night.

Many ants in warmer climates are nocturnal, but the more common UK
ones seem to be diurnal. This probably has something to do with
temperatures, as they are also more active on warm days than on
cold ones.

| If you draw any conclusions from these observations without
| correlating ant behaviour, all you will have done is observed aphids -
| yes?

Yes. I have, however, also looked for correlations, but not in
this case.

| From your observations you're convinced that any nocturnal activity by
| the ants is insignificant in respect of the study?

No. From the nature of the study. And "orthogonal" not
"insignificant".

| Did your other studies make any discrimination between species?

Of ants or aphids? Yes. In particular, I was looking primarily
at black bean and brassica aphids, but looked at any infestations
that were dense enough and on regular enough plants to analyse
patterns.

I was referring to ants in this instance - but equally it's fair to
assume that the species of both aphid and plant has a part to play.

Thanks for the clarifications - my own garden ( in particular the veg
patch ) seems to be dominated by one of the Myrmicas , which form
significantly smaller colonies than other species in the garden and
seem to be almost vagrant in their tendencies.
From my observations ( and pains ) I've seen that they're far more
aggressive and territorial than L nigra and I'm currently studying the
relationship between aphid infestation and the species of 'host' ant -
though out of the 30 or so species we have in this neck of the woods,
these are the only two that I've seen hanging around with aphids in my
garden.

The 'golden opportunity' is to catch an aphid colony where the hosts
have been ousted, and then to observe any changes in the population.
Unfortunately this isn't at all easy to do!

Regards,



--
Stephen Howard - Woodwind repairs & period restorations
www.shwoodwind.co.uk
Emails to: showard{whoisat}shwoodwind{dot}co{dot}uk