Spraying OSR

[Mersea Bees]

Hi all

The Oilseed rape where my hives are is going to be sprayed with an insecticide (Cypermethrin) on a still day next week and was wondering if anyone had any advice?? if i was to shut my bees in how long can they be kept in?
or how long after it is sprayed is it safe to let them out?

Many Thanks

Stuart

 

[mandabow]

Hi all

The Oilseed rape where my hives are is going to be sprayed with an insecticide (Cypermethrin) on a still day next week and was wondering if anyone had any advice?? if i was to shut my bees in how long can they be kept in?
or how long after it is sprayed is it safe to let them out?

Many Thanks

Stuart

no idea on timeframes, but rather than shut them in and risk the hive overheating (probably not a problem next week) or getting het up if you can provide them with a tunnel to and from some syrup for the timeframe then they are a little less upset.

get some 2mm wire mesh make a cover for your hive door ( allows ventilation)
then get some tubing, my mentor used to use old hosepipe (if its sunny cover with something to stop it getting to hot, trail it around a bit, then attach into a container with mesh roof and a slowly dripping syrup, trail the hose back to the hive, trying to make each route about equal in length so they dont just clog up one. then leave them to "forrage" you can add cut flowers/flowering potplants etc to the container at nighttime for some variety from day to day. ask local florist if you can have the stamens they cut off flowers with a lot of pollen so that they will be able to collect some of this too.

adjust flow of syrup so there is a que for it, but the box is not full of bees. if your about during the day spray extra weak syrup through the mesh top to give them specks to forrage around the box for.


i would definitely do for the pesticide spraying day, and a couple after. no idea how long stuff stays on the plants.. first rain should wash it off a bit though. maybe wait until then if it's not long?


edited to addd: quick gogling Cypermethrin is not soluble in water and has a strong tendency to adsorb to soil particles. meh

read http://www.cdpr.ca.gov/docs/emon/pubs/fatememo/cyperm.pdf 10% lost in sunlight over 32 days.. non soluble.. (tho suspends in water so will in effect still get washed off, just not as easily)

any flower that isn't open when it's spreayed is safeish.. so how long does and OSR flower last before the bees arn't interested.. your guess is as good as mine. hope for rain!! though "The experimental results indicated that cypermethrin does not penetrate the bark and
yet it is still 100% effective in killing bark beetles after 60 days from the application (Jin and
Webster, 1998)" doesnt bode well.. maybe teach them OSR is bad?!

seems crazy to covere a plant with something that will kill what it needs to pollenate it.. maybe it doesnt effect bees as bad as other insects, otherwise theire surely cutting off their nose to spite their face

 

[mandabow]

However, bees appeared to be very sensitive in laboratory tests. Under field conditions, the effect on bees is minimal, because cypermethrin seems to have a repellent effect on them

http://www.environment-agency.gov.uk/business/topics/pollution/39129.aspx says that they are repelled by it

but http://www.ncbi.nlm.nih.gov/pubmed/17879978 says it does not, but that numbers wern't affected (on that day anyway.. i can only guess they'd ahve thought to mention if half the hive was dead in a week.. gues it depends on where ther funding was comming from though

http://www.usab-tm.ro/vol8MV/75_vol8.pdf says it repels for the first day only... and http://onlinelibrary.wiley.com/doi/...ionid=33091B257D549A9455C114A041EB509B.d02t04 says one brand lasts two days

i wouldnt trust the repelling arguement, see http://www.fastcompany.com/1717421/...iation-endorses-bee-toxic-pesticides-for-cash may ahve had an influence...

but then again i wouldnt want to keep bees in for 60 days a year. can you move bees away for a week or so? if theyre in the field the hive roof, landing board etc are all going to be covered with the stuff.. not good

 

[Mersea Bees]

Thank You for the Info.

also just read this:-

Cypermethrin is highly toxic to fish, bees and aquatic insects, according to the National Pesticides Telecommunications Network (NPTN). It is found in many household ant and cockroach killers, including Raid and ant chalk.

 

[Midland Beek]

I would never lock them in. The insecticide will be on the flowers until rain washes it off, although it might be degraded somewhat by sunlight.

As long as your hives do not get a wash.

 

[mandabow]

10% in 32 days is not a big reduction in toxicity. however

http://www.springerlink.com/content/m20725418731872q/

says OSR flowers open for 3 days (bees willl probably still take the odd bit of nectar once the petals have fallen, but will be more attracted to the freshly open flowers which wont have a layer of pesticide on them.

so in lieue of anyone actually knowing (Yet-- please take their advice above mine if anyone comes forward, cos i don't know really, clutching at straws)

id say 3 days of restricted access to the OSR.. but if you can move the hive out of the area for a week or until it rains would be better. if you could talk them into spraying late evening when a high proportion of the flowers have closed at least the bees would have a safe surface to land on the next am (morning not so good for farmer as the dew would stop the insectiside being able to stick)

if you cant rig up something to keep the bees busier and can't move them close it for a couple of days(but allow ventilation) and rinse things around them down with water before letting them out.. bung up the door with a small amount of newspaper so they chew there way out early the next am when there arn't people about and hope that they go for the fresher newer flowers without the toxic chemical on.


edited to add i missread.. flowers remain open for thress days... so night time spraying only has benefit of there being a few new flowers without the next morning ...soory

 

[Chris Luck]

Presumably the rape isn't in flower so shouldn't be a problem...

"This is potentially serious because it can cause crop damage. Therefore, growers need to monitor pollen beetle numbers and apply an appropriate spray, but only if the threshold is reached."

The ADAS recommended spraying threshold is 15 pollen beetles per plant and five in very backward winter oilseed rape crops, across the field between green and yellow bud stage.

Crops are only susceptible to pollen beetle damage while they are in green to yellow bud stage, Dr Ellis added. "Once they are in flower, they're no longer at risk."

Full article..
http://www.fwi.co.uk/Articles/2011/03/29/126133/Pollen-beetles-arrive-early-in-oilseed-rape-crops.htm

Chris

 

[mandabow]

Presumably the rape isn't in flower so shouldn't be a problem...

"This is potentially serious because it can cause crop damage. Therefore, growers need to monitor pollen beetle numbers and apply an appropriate spray, but only if the threshold is reached."

The ADAS recommended spraying threshold is 15 pollen beetles per plant and five in very backward winter oilseed rape crops, across the field between green and yellow bud stage.

Crops are only susceptible to pollen beetle damage while they are in green to yellow bud stage, Dr Ellis added. "Once they are in flower, they're no longer at risk."

Full article..
http://www.fwi.co.uk/Articles/2011/03/29/126133/Pollen-beetles-arrive-early-in-oilseed-rape-crops.htm

Chris

doh i missed that bit!

should be fine then, except the day their spraying.. i'd try and move the hive if you can for the day, or close it up and cover with lots of layers of sheets/cloth (so they can still breath but it doesnt get through) until a few hours after it's been sprayed.. any bees that happen to be flying through could take it into the colony before dying.

bees are sometimes transported for hours and hours in the US.. closing the hive up for a day will make them nerky but certeinly won't cause as much damage as a cull of a load of forragers. and potential contamination of the hive with such a long lasting residue.

 

[beestingjohn]

Newbee naff question, how do arrange to get informed when spraying is going to be done locally?

 

[tonybloke]

contact spray liaison person at your local BKA

 

[beestingjohn]

Thanks, will do

 

[oliver90owner]

Sorry, people, but there is a lot of uninformed tosh being rolled around here.

Contact insecticides sprayed in the evening when most pollinators are at home in bed will be enough to kill those little unwanted beetles (by being misted by the sprayer) and after that the toxicity will be reduced to honey bees because it is a contact and not a systemic, the bees will not be working the unopened blooms, etc etc. Farmers (or their contractors) only spray enough insecticide to do the job, not enough to kill all insects within a 5 mile radius! Give them a break. They will nearly all be working within the established guidelines to avoid problems.

'I see them spraying all day long' is the shout I hear from the unknowing. Yes, they might but they are limited by certain weather factors for a start and could be spraying against something else, other than an insect pest.....Insecticides are not the only agri- icide in use, some might be enlightened to learn.

RAB

 

[Monsieur Abeille]

contact spray liaison person at your local BKA

Unless your farmers are a lot more proactive than ours, the spray liason officer normally recieves little information

 

[Poly Hive]

I no longer shut my bees in for spraying on OSR.

I cannot see any damage at all to the bees.

I took this course on the basis of advice from someone who has a great deal to lose in the event of spray issues, as in thousands of hives, and so far I have to agree with him that more harm is done by the shut in than the spray.

PH