Bee careful when using garden remedy sprays

Peter Dowdall is vociferious in his opposition to neonicotinoids — the chemicals are toxic and kill bees.

Gardening should be a healthy pursuit. It’s good aerobically, as a day spent weeding, pruning, or planting gets the heart beating, feeding oxygen into the lungs, and gets muscles moving that you may have forgotten that you had.

A good day in the garden can be better than any workout in the gym and the great thing is that you determine the pace to suit yourself; there’s no race.

But what about those that not only share the garden with us but actually live in your green space? How healthy is your garden for them?

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Many of us will have read about the dwindling bee population worldwide and many will have heard of neonicotinoids.

But how many can claim to know exactly what they are and which so-called garden remedy sprays contain these questionable pesticides?

Reports will vary on the actual value of bees to the global economy as pollinators of the world’s food crops.

It is roughly estimated that they pollinate about 70% of the crops that are used to feed over 90% of the world’s population, but the figure is largely academic: If they were to become extinct then there would be an immediate world food shortage and the prediction attributed to Albert Einstein would probably come to pass — that humans would be gone within four years of the bee.

Most amateur gardeners will come into their local garden centre if they have a query regarding plant health and they will most likely use whatever is recommended to them.

I believe there is a responsibility on professionals to inform gardeners about the dangers of using these products given the connection to dwindling bee numbers.

To that end I would urge garden centres to look for environmentally sound products to do the same thing and my feeling is if there isn’t one, then having a few holes in my roses is a small price to pay to ensure healthy bees, who are so vital to our very survival.

This problem is far from unique to Ireland. According to a 2014 study from Harvard School of Public Health, two neonicotinoids appear to significantly harm honey bee colonies over the winter, particularly during colder winters, The study replicated a 2012 finding from the same research group that found a link between low doses of imidacloprid and colony collapse disorder (CCD), in which bees abandon their hives over the winter and eventually die.

The new study also found that low doses of a second neonicotinoid, clothianidin, had the same negative effect. Both of these are covered under the European restrictions.

However, it illustrates the connection between the use of these type of insecticides and damage to the bee populations.

A more recent study from the Harvard School, published in the Journal of Environmental Chemistry, found that pesticides are in most pollen and honey samples collected from foraging bees in Massachusetts. More than 70% of the samples contained at least one neonicotinoid.

“Data from this study clearly demonstrated the ubiquity of neonicotinoids in pollen and honey samples that bees are exposed to, during the seasons when they are actively foraging across Massachusetts.

"Levels of neonicotinoids that we found in this study fall into ranges that could lead to detrimental health effects in bees, including CCD,” said Chensheng Lu, an associate professor at Harvard Chan School and lead author of the study.

Researchers analysed pollen samples during spring and summer when bees are busy foraging, from the same set of hives across the state of Massachusetts.

Scientists were able to find variations in the levels of eight neonicotinoids and determine high-risk locations or months, for bee exposure.

They looked at 219 pollen and 53 honey samples from 62 hives, from 10 out of 14 counties in the state.

In each location and month, neonicotinoids were found, suggesting bees are at risk of pesticide exposure any time they forage anywhere in the state.

Imidacloprid and dinotefuran were the most commonly detected neonicotinoids.

The pesticides that seem to be pervasive throughout the state pose a risk for the survival of honey bees, as well as a health risk for humans inhaling neonicotinoid-contaminated pollen, Lu said.

“The data presented in this study should serve as a basis for public policy that aims to reduce neonicotinoid exposure,” he said.

The pesticide industry is big business and there is a lot at play here. In Britain, the environment department has told its own expert committee on pesticides not to publish minutes of a crucial May 20 meeting.

This is to enable the government time to consider applications for emergency lifting of the bans in certain areas. These emergency applications are made by chemical companies like Syngenta, which they later withdrew, to lift the ban in July 2014.

However, if gardeners stop using these products and if garden centres stop selling and recommending these products, not only will it have a direct, beneficial impact on bees and maybe other wildlife, it will also send a clear and strong message to governments and maybe more importantly, the chemical companies that manufacture these pesticides. Quite simply if people stop buying them and there is no market, they will stop producing them.

I have sent requests for information to the Pesticide Registration and Control Division of the Department of Agriculture, Food, and the Marine which regulates pesticides in Ireland.

I was looking for a list of products containing neonicotinoids that are still available for sale in Ireland. Unfortunately I am still awaiting a response.

The European regulation imposed restrictions on three neonicotinoids: Clothianidin, thiamethoxam, and imidacloprid.

* Thiamethoxam: active substance never registered for use in Ireland in any product. Rapeseed treated abroad, imported, and drilled here was treated with this chemical.

* Clothianidin: Registered in Ireland in one product — Redigo Deter, used to treat cereal seed predrilling.

* Imidacloprid: Registered in Ireland in both professional and amateur use products. Registration for amateur use products Bug Free Extra (PCS 02262) and Provado Vine Weevil Killer (01606) was withdrawn on September 30, 2013.

Some similar actives, for example Thiacloprid, remain registered in both professional and amateur use products.