Pest and disease control
There are numerous potential pest and disease problems that must be addressed in order to produce marketable fruit. The features of the zero residue management treatment system are summarised in the table below, starting immediately after harvest.
Summary of treatments in zero residue programme
| Timing | Pest / Disease target | Treatment |
|---|---|---|
| Post harvest (conventional crop protection products) | ||
| September / October | scab / mildew | Systhane + Captan |
| October | Nectria canker | Fathom* |
| October (approx. 7-14 October) | aphids | Aphox or other aphicide but from a different chemical group to Calypso |
| Pre leaf fall | scab | urea |
| Leaf fall | Nectria canker | Cuprokylt / Fathom* |
| Winter | overwintering codling | Nematodes |
| Nectria canker | Removal in pruning | |
| Winter / spring | scab | Macerate leaf litter |
| Pre bud burst (conventional products) | ||
| Spring | scab / Nectria canker | Cuprokylt |
| Bud burst – petal fall (conventional products) | ||
| Bud burst – petal fall | scab | Dithianon / Captan / Systhane |
| mildew | Systhane or Topas | |
| Mouse ear / green cluster | tortrix / winter moth | Runner |
| Pink bud | tortrix | Insegar |
| aphids / weevils / sawfly / capsids | Calypso | |
| Blossom and petal fall | Nectria / storage rots | Bellis or Captan or Switch |
| Petal fall | tortrix / codling moth | Insegar |
| aphids / weevils / sawfly / capsids | Calypso | |
| Petal fall – harvest (sulphur, biocontrol or cultural control only) | ||
| Petal fall – harvest | mildew | sulphur |
| codling moth | Granulosis virus | |
| tortrix | Dipel* (Bacillus thuringiensis) | |
| storage rots | Rot risk assessment / Inoculum removal / Selective picking | |
* EAMU
Management of the herbicide strip
Management of the bare herbicide strip beneath the tree should be the same as in conventional production.
- Excessive weed growth is undesirable but, if carefully managed, could provide soil cover to prevent soil splash to fruit pre- harvest.
- A dead grass mulch is ideal.
- Applying a straw mulch would also prevent soil splash.
Orchard monitoring
A rigorous, regular programme of orchard monitoring for pests and diseases is vital. This enables timely corrective action to be taken.
- Orchard inspection for scab during blossom and petal fall is critical.
- If significant levels of scab are present then proceeding with the zero residues programme is not advised.
- Similarly, if a problem gets out of control between petal fall and harvest then it may be necessary to make conventional product applications to make a correction.
- This should rarely be necessary and may not result in residues if a sufficiently long harvest interval can be observed.