Last week was National Insect Week in the UK and how many of us know exactly how important these little guys are in our gardens?
Has anyone else noticed the huge amounts of ladybirds visible in the garden this year? Ladybirds are an invaluable resource for gardeners as they feed on greenfly and other aphids. If we can work with nature in the garden and encourage the beneficial wildlife there, we will enjoy much healthier and more beautiful gardens. To this end it is important that we don’t use harmful chemicals as many of them will also kill our native ladybirds and thus ensure greenfly attacks and the need to buy more insecticides for years to come.
But are the ladybirds that we have been admiring recently in larger numbers, one of our native species or are they the less desirable Harlequin or Asian Ladybird, Harmonia axyridis? This species was introduced as a control for aphids in glasshouse crop production as one beetle can eat up to 200 greenfly a day. However he has escaped into the wild and sightings have increased at an alarming rate over the last 10 years and they now threaten native species across Ireland and Europe.
The Irish Wildlife Trust in partnership with the National Museums Northern Ireland and biology.ie, are currently running a nationwide Ladybird Survey. The aim of the survey is to record the distribution of ladybirds throughout Ireland. Because the Harlequin threatens our native species it is important to know what species exist and where. Members of the public, including naturalists, school and community groups, are invited to become ‘citizen scientists’ and to submit their sightings. Look up iwt.ie for more on this. There is also some good information on the species at doneganlandscaping.com.
Many of the same insecticides will also have a detrimental effect on the local bees. The dwindling bee population has received much publicity recently and its importance cannot be overstated. Two weeks ago President Obama took steps to save bees as The White House sets up a task force to investigate the effects of insecticides on bees and other pollinating insects. I also learned recently that across Europe, including Britain, there are only 35% of bees available to pollinate food crops.
The most common problem pests for we gardeners are slugs and snails. We are infested with them because of our warm and moist climate. Hedgehogs and some larger birds are their natural predators but what many of us opt for as a control of these pests, is the cheapest slug pellet on the shelf. This is not good practice as the active ingredient in these is normally Metaldehyde which poses a real hazard to wildlife, pets and even young children. What does this also kill? You guessed it, hedgehogs and birds. Of course it is not always in the interest of the chemical companies that we have a healthy population of the predators, at hand, as then we will need less of their product.
But there are many other ways of dealing with these pests that won’t upset the natural order and indeed may well lead to an increase in the population of the good guys – hedgehogs and birds – in your garden.
Firstly try a wildlife friendly, organic slug pellet, there are several on the market and the active ingredient is Ferric phosphate which is not harmful and the dying slugs and snails burrow underground and are not available to predators. Slug traps filled with beer is one of the most effective methods of all to kill slugs in your garden. These traps are readily available and very inconspicuous. Simply fill with beer as needed and empty two or three times a week.
Be careful not to confuse slug repellents with slug killers as the repellents will do just that, repel.
They create a barrier which the slugs and snails cannot cross. Many things can be used as repellents, eggshells, cinders from the fire, coffee grounds and there are several available commercially in your local garden centre. The reason I urge you to be careful if using a repellent is that you need to create a barrier around your plants or beds that cannot be crossed but if you leave the smallest of gaps or there is a heavy shower of rain then they will find the opening and through it they will go. The advantage of using this method is that nothing is poisoned and there is a greater food source available to the predators and thus you will end up with more birds and hedgehogs in your garden and thus the natural order is being strengthened — unless you’re a slug of course.
Phasmarhabditis hermaphrodita is a parasitic nematode which is used to control slugs and is available as Nemaslug.
Your garden therefore is a better and more enjoyable place when you have more birds and other friends working with nature in this way; a truly living entity. So next time you see a creepy crawlie don’t run or go for the nearest insecticide; he could be the one that is maintaining healthy equilibrium in your garden. The balance of nature is precarious, so try not to upset it.
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