The link between phosphate and slugs

[Feldspar]

One thing that made my ears pr*ck up at the Kinsey seminar was his claim that slugs and snails were more of a problem in soils with high levels of available phosphates. He didn't seem able to provide an explanation as to why and I wondered if anyone had any bright ideas? Has anyone noticed any such link?

In conversation with one of the soil specialists here in the UK they mentioned that they thought there might be a link between the iron content in soils and the slug numbers. Where there was ferric phosphate naturally occuring in the soils there was fewer slugs. They weren't super sure but they did suggest a correlation.

Another thing that might tie into this is bits of anecdotal evidence between reduced slug numbers and applications of sewage sludge. Obviously this is high in phosphates but then if Kinsey is right one might expect it to encourage rather than discourage slugs.

All a bit confusing.

 

[BSH]

Didnt one of the German visitors say something about Zinc levels? I think he thought there was a link between low Zinc and slug numbers? Might have got that the wrong way round!

 

[Feldspar]

Yes, it was a chap called Max. I can't quite remember whether more Zinc was better or worse either.

 

[martian]

I'm sure there is some correlation, whatever element is involved. We've got some devastated wheat behind OSR which has areas seemingly untouched by slugs. These seem to match up to old field patterns (amalgamated 40+ years ago) which would explain high phosphate or whatever. I'll have to get some soil samples analysed...

 

[martian]

I don't think slugs are a particular problem (yet) in USA, Kinsey talked of slugsandsnails like it was one creature. Thinking about it afterwards, snails must need fair bit of calcium for their shells and we certainly get millions of the little horrors on the chalkier ground (the combine was plastered with snail puree last year), though they don't appear to damage the crop like slugs. Probably eating mildew and saving us a pass with the sprayer

 

[SilliamWhale]

I don't think slugs are a particular problem (yet) in USA, Kinsey talked of slugsandsnails like it was one creature. Thinking about it afterwards, snails must need fair bit of calcium for their shells and we certainly get millions of the little horrors on the chalkier ground (the combine was plastered with snail puree last year), though they don't appear to damage the crop like slugs. Probably eating mildew and saving us a pass with the sprayer

I think animals in the system somewhere help.

 

[155tm]

I think animals in the system somewhere help.

Not enough looking at some of our winter wheat following spring beans following grazed pedders.

 

[TWF]

My lighter land (limestone brash) doen't have much trouble with slugs it does have some and millions of snails. I have always beleaved the lighter land had less problems because it was light but this year and the Kinsey workshop have got me thinking. I have some brashy fields with part of them clay, You can see to the line where it is because to the line ,99% of the wheat has gone even with plenty of passes with slug pellets, yet the brash is still all there and looking good. This was all drilled with a Claydon Hybred on the 15th Sept.

I'm starting to think now that this my have something to do with taist or palability of the wheat in conection to its fertility as the slugs don't seem to be creeping into the rest of the field that has only had one pass of pellets. I am hoping to have some Albrcht tests done soon on the two halves of the field to see if I can see any trends. I did look at this system about 8-10 years ago but only half hartedly with no good result and wheat at £60/t. Whish I had had a workshop meeting back then.
TWF

 

[Desangosse Ltd]

Interesting one this...................the only correlation I can imagine would be moisture levels and the ability to lay eggs in sheltered areas below ground. I'm going to feed this one to our men in white coats and see what comes out.

 

[Colin]

Lot of balls. I have high levels of P but negligible levels of slug damage. This is on light sandy soil right enough that consolidates and makes tilth easily.

 

[Elmsted]

Lot of balls. I have high levels of P but negligible levels of slug damage. This is on light sandy soil right enough that consolidates and makes tilth easily.

We do not have slugs at all. But note that sandy beaches have snails yet no slugs. Maybe the snail lays down more slime than a slug to move over sandy soil.

 

[Colin]

Maybe in drier areas snails are more prevalent as their shell protects them from desiccation?

 

[Elmsted]

Maybe in drier areas snails are more prevalent as their shell protects them from desiccation?

Given that meta works as a killer by dehydrating slugs. Maybe you are on to something. Though primary effect of meta is to sieze jaw muscles of slugs hence dehydration. But as we all know shade allows them to recover. Whereas Draza.?

 

[Desangosse Ltd]

Given that meta works as a killer by dehydrating slugs. Maybe you are on to something. Though primary effect of meta is to sieze jaw muscles of slugs hence dehydration. But as we all know shade allows them to recover. Whereas Draza.?

Hi Elmsted - could I ask where you have received your information about the mode of action of metaldehyde. I believe you have may have been ill-informed?

 

[Elmsted]

Hi Elmsted - could I ask where you have received your information about the mode of action of metaldehyde. I believe you have may have been ill-informed?

Source is un important. What is your view of how meta works please

 

[Desangosse Ltd]

Metaldehyde works by irreversibly destroying the mucus membrane, thus leading to excessive mucus production, death occurs by the over production of energy, starvation and limiting movements. There is a paralysis of the mouth parts hence the instant stopping of feeding and consequent crop damage. The myth that re-hydration can occur is complete bo**ox. As ever, successful slug control is all about pellet quality.

 

[Elmsted]

Metaldehyde works by irreversibly destroying the mucus membrane, thus leading to excessive mucus production, death occurs by the over production of energy, starvation and limiting movements. There is a paralysis of the mouth parts hence the instant stopping of feeding and consequent crop damage. The myth that re-hydration can occur is complete bo**ox. As ever, successful slug control is all about pellet quality.

So at least we agree that meta siezes mouth parts, preventing further feeding. And we agree on de-hydrating. I shall for now accept your view that they can not recover by re-hydrating.
Where I agree and partially disagree is slug bait quality. Is it not pellet numbers that has more impact. Given that before the present mini pellets we used larger ones. Which effectively meant fewer bait stations per sq metre. Given the research on slug mobility it was therefore felt smaller was better.

Certainly the move to durm wheat based bait has improved palatibility and resistance to weather spoiling the attractivness of the pellets. But how does one explain why Draza in feild conditions appears to consistently better.

 

[Desangosse Ltd]

In agriculture, as in most other areas, it is all a balance. Draza is an effective product and is a good quality pellet but has its downfalls........

Baiting points - a real good point and issue to raise. Please, lets think of any other pesticide we apply in agriculture where we have to attract the pest to the pesticide...................... only one - Rat Bait (or pheromone traps but same principle). So therefore the key to success is the bait quality, or in this case the pellet quality. Pellet quality is made up of 4 key areas - Ballistics, Attractiveness, Palatability and Persistence. Smaller "mini" pellets do not achieve excellence in these areas and also they show a greater volume/surface ratio which increases degradation. So again, as ever everything is a balance. One might say.....in this case SIZE MATTERS

 

[John Slejpner]

In agriculture, as in most other areas, it is all a balance. Draza is an effective product and is a good quality pellet but has its downfalls........

Baiting points - a real good point and issue to raise. Please, lets think of any other pesticide we apply in agriculture where we have to attract the pest to the pesticide...................... only one - Rat Bait (or pheromone traps but same principle). So therefore the key to success is the bait quality, or in this case the pellet quality. Pellet quality is made up of 4 key areas - Ballistics, Attractiveness, Palatability and Persistence. Smaller "mini" pellets do not achieve excellence in these areas and also they show a greater volume/surface ratio which increases degradation. So again, as ever everything is a balance. One might say.....in this case SIZE MATTERS

Well that's your opinion.
Mine differs.
(Give me a mo cos i have just been spun so hard i am trying to work out which way is UP)

How have you manage to write the above without reference to the 210 gram meta limit?


Traps should be placed in suitable weather conditions using chicken layers’ mash or equivalent as bait. (Do not use pellets as bait beneath traps.) Once threshold levels are breached applications of no more than 210g/ha of active ingredient should commence.
Immediately above is a quote from the TDS Major page of your website, which i feel the need to point out is slightly ambiguous.
Second sentence should better read " ....applications TOTALLING no more than 210g/ha active ingredient should commence."
Halfway down page next to the Get Pelletwise emblem funnily enough.
Well i am pellet wise thank-you, and here to help.

So that is a total of 5.2 kg/ha of TDS allowed for the SEASON (TDS 4% meta)

Or a total of 7 kg/ha of Osarex (3% meta) for the SEASON

These are both good pellets of there type
Neither was enough baiting points.
And attracting the slugs was not the problem.
Osarex are a good pellet but need to be 1.5% meta.

TDS at 4% and the size they are are obsolete due to the 210g rule in all but some specialised situations ( lowish numbers of slugs grazing slowly emerging crop when conditions are cool and damp)

In my opinion

 

[Desangosse Ltd]

Hi John, the normal/usual use rate of TDS is 5kg/ha, giving 200g/ai per application. You are absolutely correct that we should all be observing the MSG guidelines of 210g/ai per ha and all other guidelines that the MSG promote. All we are looking to do is achieve the very best efficacy. In this case, all of our work has determined the key to successful slug control is related to pellet quality and not baiting points, but again as stated it is all a balance.

I am very happy to look at comparative trials of pellets and the success. The key for me is to highlight the fact that there are different types of pellets, different qualities of pellets and therefore different opinions and options. Growers need to be aware that they are not buying metaldehyde or "minis", they are buying a bait containing metaldehyde. I want the buyer to understand this and get the very best from his purchase. We have 30 years experience in slug control and will only sell products that we believe in.