Well. the flypaper is still catching blackfly and the war against the ants
continues but at least the aphids are very few on my runner beans - got to
leave some for the ladybirds! Talking of runner beans, I'll be picking
the first ten or twelve tomorrow.

Regards

Ron.

In article ,
Ron wrote:
Well. the flypaper is still catching blackfly and the war against the ants
continues but at least the aphids are very few on my runner beans - got to
leave some for the ladybirds! Talking of runner beans, I'll be picking
the first ten or twelve tomorrow.

Do you have a scrap of evidence that persecuting the ants has any
effect on the blackfly?


Regards,
Nick Maclaren.

On 1 Jul 2003 19:22:17 GMT, (Nick Maclaren) wrote:

In article ,
Ron wrote:
Well. the flypaper is still catching blackfly and the war against the ants
continues but at least the aphids are very few on my runner beans - got to
leave some for the ladybirds! Talking of runner beans, I'll be picking
the first ten or twelve tomorrow.

Do you have a scrap of evidence that persecuting the ants has any
effect on the blackfly?

It should do. Ants 'farm' sap-sucking insects for the 'honeydew' they
excrete, and in return they offer protection against predators.
Reduce the 'minders' and you should tip the odds in favour of the
beasties that would normally prey on the black/green fly.


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 wrote:
On 1 Jul 2003 19:22:17 GMT, (Nick Maclaren) wrote:

In article ,
Ron wrote:
Well. the flypaper is still catching blackfly and the war against the ants
continues but at least the aphids are very few on my runner beans - got to
leave some for the ladybirds! Talking of runner beans, I'll be picking
the first ten or twelve tomorrow.

Do you have a scrap of evidence that persecuting the ants has any
effect on the blackfly?

It should do. Ants 'farm' sap-sucking insects for the 'honeydew' they
excrete, and in return they offer protection against predators.
Reduce the 'minders' and you should tip the odds in favour of the
beasties that would normally prey on the black/green fly.

That is an old wive's tale.

The 'farming' ants are all tropical, and the common ants in the UK
do not even 'herd'. I have made some reasonably scientific observations
on blackfly, in my garden and elsewhere, and the evidence was that the
presence of ants makes no difference whatsoever. My observations have
been confirmed by entymologists.

Far more ants in the UK prey on aphids than protect them in any way,
and (after several years of querying in many ways), I have failed to
discover ANY evidence that ANY ants EVER increase aphid damage in
the UK. As I mention above, quite the contrary, in fact.


Regards,
Nick Maclaren.

Whatever you say, I've seen ants attacking and driving away ladybirds and
ladybird larvae so I'll continue killing ants' nests near any of my beans
and strawberries which I've seen being eaten by ants.

Regards

Ron

Ron wrote in message
...
Whatever you say, I've seen ants attacking and driving away ladybirds and
ladybird larvae so I'll continue killing ants' nests near any of my beans
and strawberries which I've seen being eaten by ants.
Regards
Ron
Ants also "raise" root aphids which attack string beans. One way to get rid
of them is to make a paste of pecans and boric acid (1 tablespoon pecans 1
tsp boric acid) and place tsp. of it around the edges of your garden or
anywhere esle you want to clear of ants.

On 1 Jul 2003 22:27:31 GMT, (Nick Maclaren) wrote:

In article ,
Stephen Howard wrote:

It should do. Ants 'farm' sap-sucking insects for the 'honeydew' they
excrete, and in return they offer protection against predators.
Reduce the 'minders' and you should tip the odds in favour of the
beasties that would normally prey on the black/green fly.

That is an old wive's tale.

The 'farming' ants are all tropical, and the common ants in the UK
do not even 'herd'. I have made some reasonably scientific observations
on blackfly, in my garden and elsewhere, and the evidence was that the
presence of ants makes no difference whatsoever. My observations have
been confirmed by entymologists.

I put the word 'farm' in quotes for that reason - unlike the tropical
species, ants here in the UK seem to have a less formal arrangement.

Anyone who's cast more than a cursory glance at a colony of aphids
will have noted the interaction of ants. Furthermore, anyone who's
watched ants attack prey will have noted a very distinct difference in
both their attitude and posture when tending the aphids.
If you drop a nice juicy beetle outside a busy ants nest, they won't
swiftly knock up a corral and hang about for another beetle to
increase their stock - they'll tear it apart as soon as they can
prevent it running away. In this behavioural context their relatively
benign interaction with the aphids suggests a degree of nurture -
hence the association with farming and herding.

I suspect that the relationship is quite a complex one.
For a start, adult ants themselves don't need to prey on the aphids
for proteins, but the honeydew is a valuable source of food for them.
Prey is required for the larvae though, and whilst ants will certainly
use aphids it seems rather more likely that the ants take advantage of
the fact that aphids attract much meatier prey in the form of their
own predators - the aphid colony acts as a self sustaining booby trap.

In effect, the ant acts as a middleman...or, dare I day, a pimp!

Far more ants in the UK prey on aphids than protect them in any way,
and (after several years of querying in many ways), I have failed to
discover ANY evidence that ANY ants EVER increase aphid damage in
the UK. As I mention above, quite the contrary, in fact.

Well, my own experience in my veg plot has been that if there's a
common black ant's nest ( Lasius niger? ) near the beans etc, then I
find I have more problems with aphids.
If I site the beans more to the centre of the patch ( whereby I can
more readily spot an ant nest, and take appropriate action ) the beans
seem to suffer far less problems with aphids.
Given that there appears to be no formal herding of aphids, then yes,
I wouldn't have thought that ants per se would increase the incidence
of aphid colonization - merely take advantage of it and sustain it.

There are cases where the relationship has a negative effect on the
aphid population - but this applies more to formal herding
arrangements combined with parasitic attack.

For an 'old wives tale' it seems to have a lot of credence out there
in the bio-community - and I'd be thoroughly interested in any
references you might have to work that throws a new light on this
phenomenon.

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 put the word 'farm' in quotes for that reason - unlike the tropical
| species, ants here in the UK seem to have a less formal arrangement.

That is true.

| Anyone who's cast more than a cursory glance at a colony of aphids
| will have noted the interaction of ants. Furthermore, anyone who's
| watched ants attack prey will have noted a very distinct difference in
| both their attitude and posture when tending the aphids.

Also true.

| I suspect that the relationship is quite a complex one.
| For a start, adult ants themselves don't need to prey on the aphids
| for proteins, but the honeydew is a valuable source of food for them.
| Prey is required for the larvae though, and whilst ants will certainly
| use aphids it seems rather more likely that the ants take advantage of
| the fact that aphids attract much meatier prey in the form of their
| own predators - the aphid colony acts as a self sustaining booby trap.
|
| In effect, the ant acts as a middleman...or, dare I day, a pimp!

I have never seen that, and have some difficulty in believing that
it is true of Lasius niger.

| Well, my own experience in my veg plot has been that if there's a
| common black ant's nest ( Lasius niger? ) near the beans etc, then I
| find I have more problems with aphids.
| If I site the beans more to the centre of the patch ( whereby I can
| more readily spot an ant nest, and take appropriate action ) the beans
| seem to suffer far less problems with aphids.

I think that can tell you why that happens, and it is almost certainly
NOT due to the ants! Blackfly overwinter on other plants, such as
Viburnum and Philadelphus. They then breed asexually, develop
winged females, fly to summer hosts like broad beans and nasturtiums
and then breed asexually like mad.

It is probably because the flying females will alight on the outside
plants first.

I have been trying to control blackfly on beans by spraying infestations
on OTHER plants (mainly those two) as the beans grow, and it seems to
work.

| Given that there appears to be no formal herding of aphids, then yes,
| I wouldn't have thought that ants per se would increase the incidence
| of aphid colonization - merely take advantage of it and sustain it.

I haven't seen that, either, and have done a test or two.

| For an 'old wives tale' it seems to have a lot of credence out there
| in the bio-community - and I'd be thoroughly interested in any
| references you might have to work that throws a new light on this
| phenomenon.

I have no references, but have found no references to ANY evidence
that ants increase the infestations either. Not one. And I have
done a fair amount of enquiring.

Observation of ants fighting ladybird larvae (even if correctly
deduced) merely demonstrate that they can conflict. I have seen
Lasius niger climbing over ladybird larvae to milk aphids, and
neither interfering with each other.

I have observed the difference between aphid infestations with
ants and without, in the same row of broad beans and in more than
one location, and could see no difference in their vigour or
progress.

I have observed the pattern of aphid infestations in many places,
and have never seen any evidence of movement by ants. In all
cases, the colonies were probably due to flying females or rain
wash. The patterns are different in all three cases.

That is why I say that it is an old wive's tale. Like many such,
it has a lot of credence and some plausible arguments, but little
evidence.


Regards,
Nick Maclaren.

I have been trying to control blackfly on beans by spraying infestations
on OTHER plants (mainly those two) as the beans grow, and it seems to
work.

I have not been "trying to control blackfly", I've been succeeding in
controlling them and I do not use sprays against them, so perhaps there
would be no infestations for you to spray if you tried what you're saying is
an old wives' tale next year.

| Given that there appears to be no formal herding of aphids, then yes,
| I wouldn't have thought that ants per se would increase the incidence
| of aphid colonization - merely take advantage of it and sustain it.

" . . . .thought . . . ."? If some are moved to pastures new . . . .

I've been keepng a very close watch on my plants (I have oodles of spare
time!) and have observed that an aphid or two first appear on the leaves of
the runner beans. These aphids, if I did not kill them, would give birth to
more live aphids until there's quite a patch of them - this too, is when I
often "squidge" them - and if I see an ant, out with the Nippon and put some
on the bamboo supports. If I did not squidge etc., aphids would suddenly
appear on nearby flower buds (not rain washed there unless water runs
upwards) and I'm convinced that ants would be responsible for moving them.
One such group of buds was removed straight away and out with the Nippon.

Many times I've tried to interest ladybirds in aphids which are "protected"
but they seem to know about the protection racket and will not attack them.
Perhaps other predators know of it too.

I agree that what I do does not equate to scientific proof and I do not have
enough money nor a large hermetically sealed environmental chamber in which
to conduct rigidly controlled experiments, but until someone comes up with a
good reason why I should not carry on the way I do, it's flypaper and death
to ants!

There is one more way to help reduce the aphids - peanuts. Peanuts to
attract bluetits, in a container having enough room for only one bird at a
time to get at them. The birds queueing up will clear aphids fairly well.

Regards

Ron

On 1 Jul 2003 22:27:31 GMT, (Nick Maclaren) wrote:

In article ,
Stephen Howard wrote:
On 1 Jul 2003 19:22:17 GMT, (Nick Maclaren) wrote:

In article ,
Ron wrote:
Well. the flypaper is still catching blackfly and the war against the ants
continues but at least the aphids are very few on my runner beans - got to
leave some for the ladybirds! Talking of runner beans, I'll be picking
the first ten or twelve tomorrow.

Do you have a scrap of evidence that persecuting the ants has any
effect on the blackfly?

It should do. Ants 'farm' sap-sucking insects for the 'honeydew' they
excrete, and in return they offer protection against predators.
Reduce the 'minders' and you should tip the odds in favour of the
beasties that would normally prey on the black/green fly.

That is an old wive's tale.

The 'farming' ants are all tropical, and the common ants in the UK
do not even 'herd'. I have made some reasonably scientific observations
on blackfly, in my garden and elsewhere, and the evidence was that the
presence of ants makes no difference whatsoever. My observations have
been confirmed by entymologists.


Regards,
Nick Maclaren.


That's interesting and worth knowing. Just curious, Nick, how did you
carry out this experimental test and was there statistical analysis?

Regards
Geoff

In article ,
wrote:

That's interesting and worth knowing. Just curious, Nick, how did you
carry out this experimental test and was there statistical analysis?

To answer the last question first: "no". But I am a statistician,
and the results were enough to debunk the theory that ants are
always the primary cause of aphid infestations. To extend that
statement to "usually" would mean a much wider set of data and,
to extend it to "a significant" would need a lot more data.

My information gathering has been on the net, reading a random
collection of books and papers and so on.

The experiments:

Looking at the patterns on blackfly infestations on my beans
and in a fair number of other gardens. Flying females produce a
scattered (nearly Poisson process) distribution, concentrated
towards edges. Rain wash produces colonies on adjacent plants
lower down and younger. Ant distribution would spread to
adjacent plants, with younger on the outside - that is IMPORTANT,
as flying females might lay eggs on adjacent plants, too.

I have never seen evidence of ant distribution.

Leaving blackfly colonies to grow on my beans, and observing
the correlation of their growth rate with (a) whether they were
near and ant's nest and (b) whether I saw ants on them. Also,
seeing whether there are ants on EVERY colony in other locations,
or only on some.

I have seen no evidence of correlation, though I would have
noticed only a strong one (which is what I was looking for).


I can fully believe that there is SOME effect, but all of the
information I have is that it is negligible compared with other
factors. It is CERTAINLY so in my garden, and I have reason to
believe that it it is so generally. That includes statements
to the effect by entymologists.

Nobody that I know of has EVER carried out a test of causality,
so there is no definite statistical proof whether killing ants
has any effect on aphid infestations or not. All my experiments
indicate is that the claims of a strong and near-universal link
are bogus.

Given space (which I don't have) and time, it would be interesting
to do a proper experiment. This would be worth repeating in a few
parts of the country, because there could well be a geographic
distribution.

It is indicative that even the pesticide manufacturers do not
provide anything for killing ants in commercial crops - this
indicates to me that few scientists believe that this is significant
effect.


Regards,
Nick Maclaren.

Nick Maclaren saud

Snip . . . . the results were enough to debunk the theory that ants are
always the primary cause of aphid infestations
Snip

I did not say "always" but once is once too often.

Snip


I can fully believe that there is SOME effect, but all of the
information I have is that it is negligible compared with other
factors

"SOME" ? nuf said there!

Nobody that I know of has EVER carried out a test of causality,
so there is no definite statistical proof whether killing ants
has any effect on aphid infestations or not. All my experiments
indicate is that the claims of a strong and near-universal link
are bogus.

It is indicative that even the pesticide manufacturers do not
provide anything for killing ants in commercial crops - this
indicates to me that few scientists believe that this is significant
effect.

They are not in business to make insecticide to help people, they're in
business to make money.

Ron

In article ,
"Ron" writes:
| Nick Maclaren saud
|
| Snip . . . . the results were enough to debunk the theory that ants are
| always the primary cause of aphid infestations
|
| I did not say "always" but once is once too often.

Even if, for every time they increase the problem, they reduce
it five times?

No, I am NOT producing a purely theoretical example - that is
AS LIKELY a possibility as the converse, based on all of the
evidence that I have seen or heard of.

| I can fully believe that there is SOME effect, but all of the
| information I have is that it is negligible compared with other
| factors
|
| "SOME" ? nuf said there!

Possibly some effect in controlling aphid infestations. Now
what do you say?

| It is indicative that even the pesticide manufacturers do not
| provide anything for killing ants in commercial crops - this
| indicates to me that few scientists believe that this is significant
| effect.
|
| They are not in business to make insecticide to help people, they're in
| business to make money.

Precisely. If this was a significant cause, they would market some
products for killing ants. They don't.

And, up until the daemoniacal Thatcher largely destroyed it, there
was a lot of independent research done by the ARC/AFRC on crop
pests - INCLUDING aphids on broad beans and wheat. They never
regarded ants as an issue.


Regards,
Nick Maclaren.

On 2 Jul 2003 13:31:12 GMT, (Nick Maclaren) wrote:


In article ,
Stephen Howard writes:
|


| I suspect that the relationship is quite a complex one.
| For a start, adult ants themselves don't need to prey on the aphids
| for proteins, but the honeydew is a valuable source of food for them.
| Prey is required for the larvae though, and whilst ants will certainly
| use aphids it seems rather more likely that the ants take advantage of
| the fact that aphids attract much meatier prey in the form of their
| own predators - the aphid colony acts as a self sustaining booby trap.
|
| In effect, the ant acts as a middleman...or, dare I day, a pimp!

I have never seen that, and have some difficulty in believing that
it is true of Lasius niger.

L.niger is, as popular parlance might put it, 'known for it, Guv'.
In areas where L.niger actively cultivates an aphid population well
over a dozen species of aphid have been found in a nest.
Naturally, their behaviour in Britain may be modified to suit the
climate, but the species has a strong herding tendency.

Their behaviour is quite distinct from Myrmica rubra, which is common
in these parts ( a fact of which I am often painfully reminded ).
Their colonies are much smaller, and the ant is rather more
aggressive. Although I have often seen them in association with aphids
I haven't as yet observed anything but the most passing of
relationships.

Which brings me to ask.. which species were you studying, and was it
the same one across the various plots?
The point also arises that one species of ant in competition with
another for the same resources may well find it advantageous to scale
up any semi-symbiotic relationships.

| Well, my own experience in my veg plot has been that if there's a
| common black ant's nest ( Lasius niger? ) near the beans etc, then I
| find I have more problems with aphids.
| If I site the beans more to the centre of the patch ( whereby I can
| more readily spot an ant nest, and take appropriate action ) the beans
| seem to suffer far less problems with aphids.

I think that can tell you why that happens, and it is almost certainly
NOT due to the ants! Blackfly overwinter on other plants, such as
Viburnum and Philadelphus. They then breed asexually, develop
winged females, fly to summer hosts like broad beans and nasturtiums
and then breed asexually like mad.

It is probably because the flying females will alight on the outside
plants first.

On my veg patch that wouldn't be the case.
The beans, and occasionally the peas, are the only things I grow that
seem to be prone to aphid attack - the salad crops I keep under
fleece.
Given that the beans are the tallest standing crop in the patch I
would think it likely that they'd be colonized wherever they were
situated in the plot - and as any cyclist will tell you, aphids can
fly quite high enough to get over most obstacles!

I certainly agree that ants, at least in this country, aren't
responsible for aphid infestations - but I'm sufficiently convinced
through observation that their presence adds to the success of an
aphid infestation.

I have been trying to control blackfly on beans by spraying infestations
on OTHER plants (mainly those two) as the beans grow, and it seems to
work.

I don't use sprays - but I find a casual stroll around the grounds and
a spot of nifty finger work keeps the little buggers under control.
It's certainly a more effective means of control than trying to
eradicate the ants.

| Given that there appears to be no formal herding of aphids, then yes,
| I wouldn't have thought that ants per se would increase the incidence
| of aphid colonization - merely take advantage of it and sustain it.

I haven't seen that, either, and have done a test or two.

| For an 'old wives tale' it seems to have a lot of credence out there
| in the bio-community - and I'd be thoroughly interested in any
| references you might have to work that throws a new light on this
| phenomenon.

I have no references, but have found no references to ANY evidence
that ants increase the infestations either. Not one. And I have
done a fair amount of enquiring.

I quite agree with regard to increasing the infestation - if there's a
relationship it's an opportunistic one.

Observation of ants fighting ladybird larvae (even if correctly
deduced) merely demonstrate that they can conflict. I have seen
Lasius niger climbing over ladybird larvae to milk aphids, and
neither interfering with each other.

I've noted that too. I've also noted that ants are sometimes reluctant
to attack prime prey ( observations, it has to be admitted, that were
gleaned many years ago by collecting suitably fierce looking bugs and
popping them bang outside an ants nest ).
I assume much of this is to do with what the "ant orders for the day"
are, and the perceived threat.

With regards to your observations, what percentage of them were
carried out at night?

I have observed the difference between aphid infestations with
ants and without, in the same row of broad beans and in more than
one location, and could see no difference in their vigour or
progress.

I've not been able to test that assertion - wherever I've had aphid
infestation on crops in close proximity I've noted either the presence
of ants, or none at all. I've not been sufficiently motivated to leave
the buggers to get on with it in the interests of analysis - though I
might pop in a stand of lupins next year to assess this phenomenon.
My lad's at that age where that sort of thing ought to prove
fascinating.

I have observed the pattern of aphid infestations in many places,
and have never seen any evidence of movement by ants. In all
cases, the colonies were probably due to flying females or rain
wash. The patterns are different in all three cases.

That is why I say that it is an old wive's tale. Like many such,
it has a lot of credence and some plausible arguments, but little
evidence.

On the issue of aphid placement, yes, I'd go along with that.
On the issue of sustainment of aphid colonies, I'd say it bears more
examination. In the meantime I'll trust to my observations and knock
back both the ants and the aphids on the veg patch.

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:
|
| L.niger is, as popular parlance might put it, 'known for it, Guv'.
| In areas where L.niger actively cultivates an aphid population well
| over a dozen species of aphid have been found in a nest.
| Naturally, their behaviour in Britain may be modified to suit the
| climate, but the species has a strong herding tendency.

Yes, indeed. There is no doubt whatsoever about the association.
The only thing that I question is the causality.

| Their behaviour is quite distinct from Myrmica rubra, which is common
| in these parts ( a fact of which I am often painfully reminded ).
| Their colonies are much smaller, and the ant is rather more
| aggressive. Although I have often seen them in association with aphids
| I haven't as yet observed anything but the most passing of
| relationships.

If it is the reddish one I have, nor have I.

| Which brings me to ask.. which species were you studying, and was it
| the same one across the various plots?
| The point also arises that one species of ant in competition with
| another for the same resources may well find it advantageous to scale
| up any semi-symbiotic relationships.

The only one I am fairly certain about is L. niger, which is the
main one I have looked at. I am no expert, and so cannot tell you
what the others were.

| On my veg patch that wouldn't be the case.
| The beans, and occasionally the peas, are the only things I grow that
| seem to be prone to aphid attack - the salad crops I keep under
| fleece.

No brassicas? A different aphid, of course.

| Given that the beans are the tallest standing crop in the patch I
| would think it likely that they'd be colonized wherever they were
| situated in the plot - and as any cyclist will tell you, aphids can
| fly quite high enough to get over most obstacles!

The only ones I can swear to as flying high are the wheat greenfly,
whatever it is.

| I certainly agree that ants, at least in this country, aren't
| responsible for aphid infestations - but I'm sufficiently convinced
| through observation that their presence adds to the success of an
| aphid infestation.

Hmm. I have observed no difference quite a lot, so my guess is
that any effect is environment dependent.

| I don't use sprays - but I find a casual stroll around the grounds and
| a spot of nifty finger work keeps the little buggers under control.
| It's certainly a more effective means of control than trying to
| eradicate the ants.

Mine is just soft soap - slightly more thorough than fingers, but
I also use them. My experience of systemic insecticides is that
they were counter-productive.

| I've noted that too. I've also noted that ants are sometimes reluctant
| to attack prime prey ( observations, it has to be admitted, that were
| gleaned many years ago by collecting suitably fierce looking bugs and
| popping them bang outside an ants nest ).
| I assume much of this is to do with what the "ant orders for the day"
| are, and the perceived threat.
|
| With regards to your observations, what percentage of them were
| carried out at night?

None. That is a fair point.

| On the issue of aphid placement, yes, I'd go along with that.
| On the issue of sustainment of aphid colonies, I'd say it bears more
| examination. In the meantime I'll trust to my observations and knock
| back both the ants and the aphids on the veg patch.

I certainly agree with the examination. I cannot claim that I
am certain that there is no effect, but I have never had trouble
with even dense ants' nests.


Regards,
Nick Maclaren.