The Problem: We have a wonderful, if very neglected orchard (25 years!) with apple, pear, cherry, plum, quince and nut trees, which we watched come into full blossom with delight and anticipation for the fruit to come! In the last three weeks, however, an army of caterpillars, which my husband is convinced are of the moth variety, have munched their way through every tree and turned the leaves into lace! It’s true that the dose of Lake District type weather we’re currently being bombarded with can’t help, but we just wondered what can be done. It’s May now – are we too late for this year?
Mike’s advice: Sorry to hear about your caterpillar invasion; because of the mild wet winter, warm April etc, slugs, snails – and caterpillars – are having a ball; anything edible is being devoured.
Spraying your trees would be a waste of money and time and if as you say the leaves are like lace, then its probable the culprits have moved elsewhere.
What I would suggest is to put ‘grease bands’ on all your trees, now: OK, again it would seem a bit late, but some of your ‘livestock’ is likely to be still munching.
Place two bands per tree, one about 2 (two) feet from the base, leave a 12 inch gap, and then the second band; this will trap from above as well as from ground level.
I am assuming that the orchard has been neglected so, it is possible the branches from each tree are crossing over – this enables all types of bugs to transfer from tree to tree.
So come the autumn, prune the trees, leaving a good ‘air space’ between each tree, and then spray.
In your case, it is difficult to suggest a suitable spray that would be available for your orchard. You can obtain in most garden centres a powder or spray which is sufficient for one or two trees, but not for an orchard. I would, therefore, visit your local farmer’s Co-op and ask if they will supply you with DIMILIN (Dimilin Flo) or a make of spray containing DIFLUBENZURO 500 ml.
You will find it is expensive, but it does work. But use with great care.
Spray in the autumn when leaves have fallen (if there are any left), and again in early spring, before the flowers and leaves appear. DO NOT spray now, you will kill the tree. When spraying PLEASE follow instructions; if in doubt please contact me.