Sunday, August 12, 2012

Sharing With the Pests

When I was a kid I once threw a huge flip because the homegrown pear I was eating had a dead wasp in it. A big huge bite uncovered the expired intruder deep in his fruity tomb.

My grandad, who had grown up in the countryside, was far less squeamish about insects and bugs. He reprimanded me for being such a sissy (as gnarly grandfathers are wont to do) and took out his trusty pen knife to shuck away the damaged part of the pear - handing the rest of it back to me to finish eating it - which I did, albeit in somewhat more cautious bites.

He had a point. Over the years our attitude to pest damaged food has become quite ridiculous. In the west we simply throw anything away that has a nibble - be it holey greens or part fouled fruit. 

Inspecting the strawberries for pest damage.
However recent scientific research has shown that nibbled and holey greens contain additional chemicals which have been generated by the plant itself in order to fend off pest attacks. It turns out that these chemicals contain anti oxidants which are of particular benefit to humans when we eat these "holey" foods. So pre- nibbled food might actually far better for you.

Nibbled plants also produce chemicals to attract predatory insects - greens being mauled by caterpillars will eventually exude a substance which attracts wasps, which in turn eat the caterpillars.

This year we've had to share our strawberries with the slugs in a big way. It's been a bumper year for slugs in Ireland. I've never seen so many, in such large sizes and in so many different varieties. I think there's good evidence to suggest that this time they may have overpopulated.

"Ow, ow, owww!" Desperate slugs sliding over dry gravel yesterday.
They seem particularly desperate for food. I've watched them nibbling at greens they've never bothered with before, notably the leaves of foxgloves. I've also seen them moving in dry conditions, perhaps in an attempt to get ahead of the posse in the hunt for food. I've seen them eating one another, as I mentioned in a previous recent post. I'm seeing them travel over surfaces they normally avoid - over dry gravel and across the bristles of horse hair mats.  I've even seen them moving along the washing line suspended high in the air.

The slug plague hasn't boded well for my strawberries which have just faded out of season. This year they fruited extremely well, but the slugs have put big holes in at least half of the fruits. My one-and-a-half year old son loves his strawberries and regularly makes his way to the strawberry patch to raid it. So slug pellets are out.

Our other big strawberry pest is on the mooch...
With about half of the fruit ending up holey and a quarter of them about 50pc eaten, the temptation is to throw the damaged fruit into the compost bin. But that's just too much wastage for me to countenance.

In our household at least, they get washed and the holed parts are cut away so all surfaces have been cleared of areas which have had contact with the pests. Usually I end up with a clean half or a quarter fruit each time, which is better than nothing. It means I can save about a quarter of the crop by weight overall that would ordinarily get thrown away. 

I also leave some of the larger holed behind fruit on the plants to give the slugs an easy target and to act as a decoy from the soon-to-ripen fruits.

Last year it was vine weevils, this year it is slugs, next year it will no doubt be the birds or something else. There's always something. And while we'll always do our best to minimise the damage, we also have to accept that pest spoil is a fact of life with home grown food. So let's not defeat our own efforts by consigning every pre-nibbled example to the compost.
Nibbled and mauled but still usable

In contrast, today I picked some berries from a completely untouched strawberry plant located elsewhere in my garden. There were four or five juicy fruits, albeit small ones, which had not been molested by the slugs at all. 

So what's the difference between this plant and my other strawberries? 

The latter is in fact a "wild" strawberry variety of the sort that has been growing free in Irish and European temperate woodlands for thousands of years. The slug hammered varieties (see the picture above) - are all from the most commonly grown commercial varieties in Europe (like Elsanta) which happen to have their relatively recent origins in the USA and South America. These have only arrived here in the last few hundred years.

 What it does illustrate is that mother nature has provided the local varieties with all the necessary defenses against the slimy predators. Which of course begs the question: Why do we bother at all growing "higher yielding" imported varieties that can't defend themselves - especially if we either end up losing most them to pests or else spending huge amounts on pest control? Perhaps wild strawberries demonstrate that the answer to proper pest control might just have been on our doorstep all along.

Wild boys! Too much for gravel hardened slugs to handle..

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