Growing fruit trees - Organic vs Un-treated

[orangepippin]

Prompted by a recent post, I thought it is worth mentioning the difference between "organic" and "un-treated" growing regimes. The two are not the same.

Whilst organic growers make use of natural predators and good husbandry techniques it is important to note that UK organic farming standards still allow the use of fungicides based on copper salts, potassium bicarbonate, and sulphur compounds. Certain mineral fertilisers are also permitted in some situations.

For commercial-scale "organic" fruit production it is perhaps inevitable that such chemicals have to be used, but I suspect most gardeners and community orchard projects would prefer to adopt an "un-treated" or "no spray" regime.

[sugar]

I'm somewhere in between.
I won't use copper compounds. I will probably use Sulphur compounds when necessary (not used over the last two years), and I also use natural predators which sometimes need spraying (eg Xentari BT).
Main emphasis is however on planting fruit varieties that are less sensible to the typical issues 'requiring' spraying (= good husbandry).

[boundtothesoil]

I'm definitely on the 'un-treated' side of the fence, using no sprays whatsoever and no manufactured inorganic fertilisers.

My biggest beef is with sprays of any sort, for all the usual ecotoxicological reasons. But what concerns me the most about them - and I don't think the organic movement highlights this sufficiently - is the almost complete lack of empirical scientific evidence regarding the interactions between more than three or four synthetic pesticide compounds, with respect to their impact on either the environment or human health, either in the short term or the long term. Such 'multifactorial' experiments/trials are too large and complex to perform/fund and always have been. Throw in a couple of environmental variables (e.g. temperature and light), or a further interaction with some other rogue compund in the environment (e.g. a synthetic oestrogen) and who knows what the damage may be, to which species? No one! You can bet your boots that the four,five or six component tank mixes of pesticides used in conventional orchard spraying programs have not been tested/trialled in this way by the manufacturers. The same can be argued, albeit to a less potentially frightening extent, for the Copper, sulphur etc compounds allowed in 'organic' systems.

I agree with 'sugar' that a combination of good husbandry and carefully selected 'disease resistant' varieties can compensate for the absence of spraying in the case of many pests and diseases, provided you can personally attend to your trees on a regular basis throughout the growing season. Scab and Codling moth are the exceptions in my experience, and in a bad year even these can be tackled to some extent by judicious thinning of fruit right up until harvest.

[FB.]

Scab and Codling moth are the exceptions in my experience, and in a bad year even these can be tackled to some extent by judicious thinning of fruit right up until harvest.

Codling moth are attracted to certain varieties but not interested in others. Summer and early autumn eating apples directly descended from Worcester and Discovery - and also Ellison's Orange - tend to bear the brunt of attacks in my area.
Discovery, Scrumptious, Ellison suffer heavy attacks in most years (Discovery and Scrumptious also suffer badly from bitter pit which can mean no usable fruit in some years).
Of the earlies, Beauty of Bath, Irish Peach and Laxton's Epicure do not suffer much - at least, not while the maggots and wasps are busying themselves hollowing-out the nearby Discovery apples.

The fact that those three (BoB, IP, LE) - at least for me - tend to go from horrible-tasting (hard, green, acid) to fully-ripe and dropped off the tree in about a week is probably their main defence since the pests only have a few days window of time to find them in a pleasant conditions before they are picked or drop.
Discovery, on the other hand, sit there like bright red, scented beacons all through the growing and ripening process of the fruit.
The reddest, sunniest side of the apples tends to have almost all of the codling maggot holes, which confirms to me that the codling are being attracted by the red or its scent.

Features which particularly attract codling are:
1. Lots of red colour.
2. Fruit which is red coloured even when unripe (varieties which colour-up only in the few days before ripe tend to escape codling, wasp and ant attack).
3. Thin skin.
4. Soft flesh.
5. Sweet and tasty.
6. Scented eating apples.

Characteristics which deter codling:
1. Dull coloured fruit.
2. Tough or russet skin.
3. Firm/dense/hard flesh.
4. Cookers or late-ripening types.
5. Varieties which need to ripen in storage.
6. Triploids.
7. Early and mid-season fruit which remains green until colouring-up orange-red only a few days before it is ripe.


Of course, nowadays BoB, IP and LE are "relics" which no longer suit modern growing requirements. But they originate from a time when codling was not so easy to control. Maybe our ancestors were not as stupid as we think they were.

Tough skin and triploids are also useful for resisting scab - although the common triploids such as Bramley have been grown too much for too long and the diseases have had many decades and millions of trees to perfect the art of defeating the scab resistance.

I swear by the rarer triploids for their outstanding resistance to pests, diseases and ability to live a long and healthy life in difficult conditions (if their rootstock is up to the job).

Triploids are very rare from seed - about one in a thousand. But a much higher proportion of apples in cultivation are triploid than you'd expect from the one-in-a-thousand pips.

For those wanting to breed triploid apple varieties, the use of a tetraploid parent - such as the mutant forms: Jonathan-4N, Jonathan-4X or Spartan-4N - should result in almost all of their offspring being triploid (whether they are the pollen parent or the seed parent).

Jonathan also has the plus point of partial resistance to woolly aphid and production of burrknots - both useful attributes for rootstock production.

I also have a suspicion that Laxton's Epicure (or at least my so-called Epicure) is tetraploid.
Its huge, thick, glossy leaves, huge flowers, huge seeds (triploid seeds, flowers and leaves are usually much larger-than-average), sparse branching, high fertility/fruit-set, hyper-vigorous growth when young all being consistent with other plant species know to be tetraploid.

[orangepippin]

You can bet your boots that the four,five or six component tank mixes of pesticides used in conventional orchard spraying programs have not been tested/trialled in this way by the manufacturers. The same can be argued, albeit to a less potentially frightening extent, for the Copper, sulphur etc compounds allowed in 'organic' systems.

I would suggest it is the other way round. One of the complaints by conventional fruit growers against organic growers is that conventional sprays are highly regulated and controlled, both during development and when used by the grower, e.g. with regard to residues and time between spraying and harvest etc. In contrast there are fewer regulations about the manufacture and use of organic sprays, and perhaps less knowledge about their side-effects.

I'm not sure that organic fruit growing is necessarily any safer than conventional regimes, it is certainly not as safe as un-treated.

[boundtothesoil]

Codling moth are attracted to certain varieties but not interested in others.

Thanks this is really useful information FB. I've observed and recorded the Codling moth problem in my (unsprayed trees) for several years and agree very much with what you say about very early varieties escaping attack, pretty much every year. I have a single 12 year old Beauty of Bath tree and I don't think I have ever seen a single infected fruit (no scab either on this variety).

My worst variety is also Ellison's Orange. I have a 15 yr old half standard tree on an unknown rootstock and regularly lose 40% of fruit to Codling moth. The most severe attacks occur on the upper branches (reddest fruit?). Lower, shaded, green fruit seem to escape attack. I've noticed that the moths like clusters of three or more apples with plenty of leaves around them- presumably this provides cover - and the caterpillars often emerge from one of these apples and bore straight into a touching neighbour.

Some of my triploid varieties also suffer badly, in particular Tom Putt (often 30% of apples infected) - another red apple, and Bramley's (10-20% infected). The Bramley's may be a special case as there is an ancient, neglected standard Bramley's tree in the field next door. This is plastered with scab and has a 30% Codling moth infection every year (a great ecosystem but just a local disease reservoir as far as my trees are concerned) -my Bramley's suffered badly from scab this year in particular.

I use pheremone traps to estimate numbers of moths but don't practise any control measures other than keeping chickens and removing infected apples as I find them, relying on natural predators (insect and birds). Fortunately, there are a lot of blue tits and great tits around and I've seen them at work. I came across a research paper on the impact of these bird species on pest control in organic orchards in the Netherlands. The authors concluded that they had a significant positive effect and recommended installing bird boxes. However, I've found that they are a mixed blessing, pecking holes in the necks of Conference pears, also damaging Discovery and Ida Red.

Some of the other varieties I've found to be resistant/unattractive to Codling moth, at least in West wales, are Lord Lambourne (bad sawfly though), Sunset, James Grieve, Adam's pearmain, Egremont Russet and Winston.

[boundtothesoil]

I'm not sure that organic fruit growing is necessarily any safer than conventional regimes, it is certainly not as safe as un-treated.

Point taken, certainly as far as un-treated goes. I'm no expert on pesticides, but I'm still not sure that I'd prefer to drink a measure of the latest 'tested' organophosphorous-based insecticide rather than copper sulphate! Without looking them up, I imagine that most of the effective chemicals approved for use in organic systems are essentially simple Victorian nasties, whilst the roster of conventional pesticides stem initially from the synthetic chemistry revolution post Second World War. What also worries me about the latter is the regularity with which (a) they are withdrawn from use or progressively restricted and (b) are implicated as adversely affecting this or that species (i.e. recently bees).

I'm not particularly sanguine about the UK's residue contamination testing of either fruit/vegetables or fields/orchards. Presumably this now comes under the Food Standard's Agency remit - perhaps subcontracted - . I half recall looking at a recent annual results summary for this a few months ago and being surprised by both the tiny number of samples taken and the absence of exhaustive testing of all compounds in use. Then there is the matter of growers conforming 100% of the time to the regulations for their use. Who knows? It's so easy to cheat when no one is looking. And then there are the regulations themselves. Like most quangos, I would bet that the Pesticide Advisory Council/Body, or whatever it calls itself now, has a pretty strong commercial presence on board. Not that I mean to sound cynical or anything...!! Talking of which, it would be interesting to know how many certified organic producers cheat with respect to the use of fertilisers and pesticides, for example, in the name of economic necessity. Again I guess we will never know. I'd better stop right here.

[orangepippin]

I have often been told of an organic apple orchard in Holland which is surrounded on all 4 sides by conventional orchards, although this might be just one of those stories. However such a setup would provide a very effective barrier to bugs, through the use of conventional sprays in the surrounding areas. Not quite in the spirit of organics, but certainly within the letter!

[Feral007]

I have to spray on the farm, but I don't spray in the garden. It remains to be seen what we can grow without doing so. It's pretty hard soil and weather here, but I'd rather do what we can to increase the health of the plants, and then not replant the ones that can't cope.

[FB.]

From my experience and observations, the most resistant of those that I've grown to codling moth are:

(bear in mind that the presence of highly susceptible varieties may be drawing attacks away from my others - a single tree on its own gives the maggots no choice of what to attack):

Very resistant (say one in twenty apples damaged in an average year):
Fiesta (Red Pippin)
Grenadier
James Grieve
Reverend Wilks
Spartan

Fairly resistant (say one in ten apples damaged in an average year):
Annie Elizabeth
Ashmead's Kernel
Beauty of Bath
Belle de Boskoop
Blenheim Orange
Bramley
Crawley Beauty
Court Pendu Plat
D'Arcy Spice
Edward VII
Egremont Russet
Gascoyne's Scarlet
Golden Delicious
Howgate Wonder
Irish Peach
Jupiter
Laxton's Epicure
Laxton's Superb
Norfolk Beefing
Tydeman's Late Orange
Winston
Winter Gem

Fairly susceptible (say one in three damaged in an average year):
Pinova
Red Devil
Suntan
Worcester Pearmain

Very susceptible (say on in two damaged in an average year; almost all destroyed in a bad year):
Discovery
Ellison's Orange
Scrumptious

[boundtothesoil]

From my experience and observations, the most resistant of those that I've grown to codling moth are:

What a useful listing. You have many more varieties than I grow, but mapping my observations onto yours, the only significant differences would be that my Discovery are not usually severely attacked (one in five in a bad year), and my Bramley's are definitely one in five in an average year. I could add Sunset, Emneth Early and George Cave all as 'fairly resistant', the latter two varieties being very early and Sunset almost russetty in skin tone for me.

Looking at your fairly susceptible and very susceptible categories, it strikes me that four out of seven are relatively new varieties (Pinova, Red devil, Suntan, Scrumptious?). Rather an unfortunate trend maybe.

I've had a real problem with Worcester Pearmain over many years and have now given up trying to grow this variety, having lost several trees to canker. What's more, every year nearly all the fruit were scabby and/or attacked by Codling moth.

[yummersetter]

Just to add my tuppenceworth, I don't think I've found any codling moth this year. Maybe they've all drowned.

[FB.]

Just to add my tuppenceworth, I don't think I've found any codling moth this year. Maybe they've all drowned.

2012 was one of my least affected years. Most varieties escaped attack.

[FB.]

strikes me that four out of seven are relatively new varieties (Pinova, Red devil, Suntan, Scrumptious?). Rather an unfortunate trend maybe.

Maybe because modern varieties are selected to be colourful - and as per my comment about the colourful sunny side of a red apple being the most likely to have the maggot entry hole.

The codling appear to be able to zero-in on the red pigment in certain early varieties in particular. The more purplish tint of Spartan fruit must be a different chemical (anthocyanin?) which is less attractive, or maybe the thicker skin or different flavour of Spartan isn't to the taste of the maggots.

Apparently, studies have also suggested that the less-common apple sawfly zeroes-in on certain UV-reflecting shades of petal colour, where it then lays its eggs.

[orangepippin]

I am not convinced that codling moth attacks are strongly related to variety, although that might be a factor. For a start, apple fruitlets don't necessarily have much colour in June / July, and the extent of red colouration is often dependent on climate and may only develop in the last few weeks before picking. There can be several generations in a summer though, and perhaps the later generation does target redder apples.

The prevalence of codling moth is mainly affected by climate and orchard hygiene. If you live in the south of England, and have a period of good summer weather, and don't keep the floor of the orchard clean then you are likely to get codling moth in your apples, regardless of the variety. Once codling moth is in an area it tends to stay there.