Insects in fruit trees

In spring we reckon it’s a good idea to visit your fruit trees at least once a week, and have a really good look at the leaves, flowers, fruit and bark. It’s a good way to keep track of the health of your tree, and stay ahead of any disease issues that show up.

One of the more interesting looking insects you might see on your fruit tree
One of the more interesting looking insects you might see on your fruit tree

While you’re there, try to spot any critters living in and around the tree, like this great bug we found on an apricot tree.

It doesn’t matter if you can identify the bug or not (though that can sometimes be useful) – it’s safe to assume that it’s playing an important role in the ecosystem (like pollination, pest control, or acting as a food source for someone else), even if we don’t know what that is.

A bee working hard on a peach flower
A bee working hard on a peach flower

Many people mistakenly think pollination depends solely on bees, whereas in fact many insects play an important role (you can find out more about this important topic in Bees and Pollination).

Though it’s absolutely fascinating trying to figure out what sort of bugs you’ve got, identification is much less important than the fact that you have lots of biodiversity in your garden or on your farm. In short, the more different types of bugs you can count, the healthier your system is.

Amazing antennae...
Amazing antennae…

Why is biodiversity so important?

We often get questions from people who have noticed bugs or insects on their fruit or trees, and are wondering if they should get rid of them, and if so how?

That’s not our approach at all!

In a healthy, biodiverse system there should be literally thousands of different types of insects around, and they all play a part in an incredibly complex system that (if it’s not interfered with) will generally keep itself in balance.

Unless you’re an insect specialist, there’s little chance that you can identify them all or even understand whether they’re a “pest” or a “predator” – in fact, many are both. For example earwigs are a dratted nuisance in apricot and cherry trees, but a useful predator eating up millions of aphids in apple trees.

An earwig on a leaf  - pest or predator (or both)?
An earwig on a leaf – pest or predator (or both)?

So we take a different approach.

Rather than focusing on the insects themselves, we focus on protecting our fruit and our fruit trees from damage.

The methodology we use, both on the farm and in our ebook What’s Bugging My Fruit? is not to try getting rid of the bugs (which is usually impossible, frustrating and expensive), but to understand their life cycle and look for vulnerabilities where we can often use small, easy, physical interventions to stop them doing damage to our precious fruit. Over many years of growing fruit organically we’ve found this method much more effective.

So when you’re doing your weekly inspections of your fruit trees, look for bugs, but also look for damage on the fruit and the trees, because that’s what will guide you as to the appropriate prevention techniques.

A spined predatory shield bug
A spined predatory shield bug

What’s worse than finding a worm in your apple?

Worms in apples are scary and revolting – particularly if you only find half a worm, right?

A classic grub in the apple ... aka Codling Moth larvae
A classic grub in the apple … aka Codling Moth larvae

Apart from the visceral disgust of biting into an apple and finding that something beat you to it and is already living inside, it also downgrades the quality of the fruit.

Apples that have been infected with Codling moth are much less usable, and less valuable for all these reasons:

  • the apples don’t keep as well;
  • infected apples aren’t suitable for long term storage;
  • they’re more likely to be attacked by diseases (e.g. rots) and even other pests;
  • they can’t be sold commercially if infected;
  • they look bad so you don’t want to share them friends and family;
  • having to cut the affected part out before cooking or eating is very wasteful.
Apples riddled with the evidence of Codling moth infestation
Apples riddled with the evidence of Codling moth infestation

If the grubs have left the apple this can be even worse, as it tells you that the grubs were able to complete their life cycle and go on to breed again, perpetuating your Codling moth problem and increasing their population.

So, what to do?

Codling moth is one of the more challenging pests that fruit growers have to deal with, but don’t despair, there is a way! Here’s our 6-step plan for getting on top of them:

  1. First, find out whether Codling moth are a problem in your area. If you already have them in your apples, this one’s a no-brainer, but if you’re new to fruit growing you may need to ask around other fruit growers in your area to find out if it’s something you need to be prepared for.
  2. Learn how to identify them.
  3. Understand their life cycle. Good organic pest management depends on knowing your enemy! Every pest (and every disease for that matter) has at least one weak point in their life-cycle when it’s easy (or at least possible) to intervention that will interrupt them to reduce or prevent the damage they do, and over time to hopefully eradicate the problem.
  4. Familiarise yourself with the many tools you can use against Codling moth – including trapping, banding, pheromone ties, chickens, predator insects, etc.
  5. Decide which one will work best for you, and write your own Codling moth plan.
  6. Conquer the Codling moth!
Codling moth pupae and larve in a trap
Codling moth pupae and larve in a trap

These steps are covered in more detail in the Conquer Codling Moth short course, which also includes a step-by-step process for writing your own plan.

If you already have Codling moth in your apples and are not taking active steps to control them, they’re likely to get worse. Because they complete most of their life cycle inside the apple or hidden in the soil or the bark, they’re not easy for predators to find.

Unless you intervene to stack the odds against them, in un-managed apple trees the problem tends to grow.

Ignore them at your peril!

Earwigs – love them or hate them?

This week we’re talking about earwigs – should we hate them, or love them?

A nest of earwigs in a crack in a fruit tree
A nest of earwigs in a crack in a fruit tree

There’s nothing like finding a writhing nest of earwigs in a crack in a peach tree when you’re pruning (watch the video¬†here) to reminder you that it’s time to take some steps to prevent these apparently insignificant creatures from wreaking havoc in your stone fruit trees.

What other insects are in this category? The other main one that causes an issue for a lot of stone fruit growers is garden weevils, but there are lots of insects that can walk into your fruit tree and make a mess, such as harlequin bugs and many different types of weevils.

As we’ve mentioned in other blogs, the key to effective pest and disease management is to figure out how to protect your trees (or fruit, depending on the pest) from the pest, rather than trying to get rid of the pest (which is expensive, ineffective and may even be damaging to your ecosystem).

So, how to prevent them?

Using sticky tape for earwig control in a nectarine tree
Using sticky tape for earwig control in a nectarine tree

Using our first principles of pest control, first look at their life cycle. These pests overwinter in cracks in the bark in your tree, or in the soil or litter under the tree.

They also love fence lines, bits of wood, or in fact anything lying around on the ground that provides them with darkness and shelter.

In late winter/early spring, young hatch and they start moving and will often head up into your fruit trees as soon as there are buds or fresh new leaves to munch on, even before there’s any evidence of fruit.

The key to controlling them is understanding when they’re likely to be moving (Answer: in late winter/early spring), how they get where they’re going (Answer: they walk up the trunk) and what they do when they get there (Answer: hide in a dark place during the day and come out at night to eat your fruit! Some individuals may leave the tree to return to a nest elsewhere, but they may also just take up residence and stay in the tree, making it hard to get rid off them once they’re there.).

This is the approach we use with all our organic pest control, and the basis of our short course Protect Fruit Trees from Pesky Pests which not only covers earwigs, but also bugs, weevils and all the other common pests.

Once you know all that, figuring out how to prevent them becomes relatively easy – you just have to provide a barrier they can’t walk over, and you have to do it earlier rather than later.

On the farm we do this with double-sided barrier tape, but you can achieve the same result with anything sticky – horticultural glue, or even a layer of grease (but put a physical barrier such as plastic wrap around the trunk of your tree first so you don’t hurt the tree).

If you haven’t experienced earwig damage in your fruit before, here’s just one example (below) of what they can do.

Earwigs that have taken up residence inside a peach
Earwigs that have taken up residence inside a peach

If numbers build up enough, they can be as devastating to your crop as birds, and really need to be taken seriously. Having said that, as trees get older and larger and bear bigger crops, you may lose a smaller proportion of fruit and the damage is often confined to the lower branches, but it’s still a pest worth preventing.

An earwig inside an apricot
An earwig inside an apricot

So, having decided that earwigs and garden weevils are most definitely a pest, why ask the question about whether to love them or hate them? Surely we just hate them, right?

It’s never that simple! Turns out that earwigs are also a wonderful predator of aphids (particularly the very messy white Woolly Aphids that can appear in your apple trees), which is a great example of why it’s never a good idea to kill insects – just encourage them to hang out where they can do the most good and the least damage in your garden!