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Another scary reason I buy organic

25 Sep

My struggles with Queensland Fruit Fly in my apples and tomatoes got me thinking. How do they control the little blighters commercially?

So I did some reading, and I’m deeply uncomfortable with the results.

I’m not a scientist, and I know that it is easy to get the heebie-jeebies about things that sound scary because you don’t understand them. I was trying to keep an open mind.

But here’s what I found:

Up until September 2011, tomatoes in fruit fly affected areas of Australia (including Bowen, Bundaberg and South-East Queensland) were sprayed several times during the season with the insecticide dimethoate (also known as Rogor and Lebaycid). They were also dipped post-harvest in the chemical to kill any remaining fruit fly inside the tomatoes. I believe that this was mostly for export purposes, so tomatoes could be sent to New Zealand (where they don’t have fruit fly).

Dimethoate is a systemic insecticide. That is, it is absorbed by the plant and affects the plant tissue. The buggies bite the plant and die, so it’s really affective, but worryingly, it cannot be washed off.

In September 2011 it was determined that the levels of dimethoate could exceed the levels that were considered safe. The Australian Pesticides and Veterinary Medicines Authority (APVMA) therefore suspended its use in tomato (and many other food crops). It is still allowed to be used pre-harvest before fruit set for fresh tomatoes, and pre-harvest with a 21 day withholding period on tomatoes for processing.

My concern is : Why was this chemical OK last year and under a cloud of suspicion now? I understand that this suspension is a measure of caution and that a large margin of safety is built into the recommended public health standard, but seriously (now I’m losing my composure) why were we eating tomatoes dipped in toxic stuff that will kill a bug on the INSIDE?

References :

Fruit Fly Battle 2012-13 / Episode 1

18 Sep

The weather is warmer, I’ve sown my seeds and started renewing the beds. Now it’s time to start considering my pest control measures for the coming summer.

Last year I had battles with a few peskies, including:

  • Citrus Leaf Miner
  • Slugs
  • White cabbage moth caterpillar
  • Bronze orange bugs (stink bugs or shield bugs)
  • Aphids

But the mother of all heartbreaking evil was Fruit Fly. They attacked my apples and decimated my stone fruit and tomatoes. I even noticed that a few capsicum were stung late in the season.

Last year I waged an almighty battle against them with exclusion bags, and had some limited success in the apples and tomatoes. I had difficulty bagging some of the fruit, some fruit was stung through the bag when the fruit touched the sides, and another problem was simply having enough bags to cover all the fruit. This year I’m prepared to bag again, but I think I need something else to add to my arsenal.

Eco Naturalure Products

Last week I picked up an eco-trap and some eco-naturalure from the nursery. They are produced by Organic Crop Protectants and are organic measures against Queensland and Mediterranian Fruit Fly. They are approved by BFA and have no withholding periods – you can pick fruit straight after spraying.

I might be a little slow, but I had difficulty understanding the material supplied and the information about the product online, so I thought I’d explain with some pictures.

There are two separate products here. The trap product (eco-lure fruit fly trap) comes with the bag inside. The little white tub is the eco-naturalure – more about that later.

The Eco-Lure Trap

The first step in this process is to set the fruit fly trap. The trap contains both an attractant and a poison.  This is partially a diagnostic measure (it tells you when the flies are active), and also preventative. The trap is hung in your tree, attracts the male fly and kills it so it cannot  mate with the females.

You open the bag and put the trap/lure together. Just make sure you remember to put the yellow lid between the orange hook and the (round) lure. I forgot and ended up having to straighten the hook and weave it awkwardly through the hole in the lid.

You then hang the trap in your tree at about eye level, as straight as you can (which in my case wasn’t really well straight at all).

Once you have caught yourself a male fruit fly, you know that the soil has warmed enough for the young flies to have emerged from their pupae and control measures must begin. This is where the little white tub comes in.

The Eco-Naturalure Spray

The white tub contains a thick brown sticky substance. It is both a protein attractant  for the flies (male and female) and a naturally-derived pesticide, Spinosad. The sticky stuff is watered down 6:1 and sprayed (or painted) onto the trunk of the tree or a surface near the base of the tree.

A word of caution. Spinosad is not only toxic to fruit fly – it will also kill bees. For this reason I won’t be applying it to the foliage anywhere near where the bees are foraging. I’ll be only applying it to the lower trunk of the tree until all the petals have dropped from the flowers. Bees are our friends, and I wouldn’t have any apples at all without them.

Some people apply the naturalure to cards or plastic-covered bait stations, but the instructions recommend the trunk or foliage of the tree itself. The important thing is that the sticky stuff stays damp enough for the flies to feed from, so you can’t paint it onto raw wood or anything that will absorb the moisture in the spray. Rain also washes it away, so you need to re-apply if it gets wet.

So I set my trap in my Dwarf Tropical Anna tree yesterday. And today, the 18th of September – I find this.

Fruit flies – already – in September!

But true to my luck, this afternoon it rained so I couldn’t apply the naturalure. It might even be too late.

Too Late Already?

As soon as the female fruit fly emerges from her pupa, the first thing she does is feed. She feeds from a protein source, usually animal droppings/manure/compost. My chicken coop won’t be helping things here.

If the most attractive thing she finds to eat is the spray, then she dies right there – end of story.  If she eats something else, then she has a chance to mate. She may not even feed again, therefore bypassing any baits and laying her eggs in my tasty fruit – fruit fly win.

So the fact that I caught at least 6 males on the first day I set the trap suggests that they have been active for a while, probably even from August. Some females have already emerged, fed and are ready to lay some eggs. I need to hurry up if I want to have any success of controlling them to any extent.

So this morning after checking my trap I set to work thinning apples and bagging the larger ones with exclusion bags. I thinned more than 100 fruit, with an eye to limiting the number on any one branch, but also thinning those that are in locations that are difficult to bag. I didn’t really even make a dent in the fruit set though – both my warm climate apples have set many hundreds of fruit – much more than the trees can support.

Tomorrow I’ll be spraying the trunks and hoping with all fingers and toes crossed that I’m not too late.

Does anyone have any pest control anecdotes or words of wisdom to share with me?

Protecting tomatoes from fruit fly

24 Feb

Never before have I had problems with fruit fly. So much so that I didn’t know what they actually looked like or how much of a menace they are. This year however I’m growing a larger variety of fruit, including large slicing tomatoes. I’m no longer so naive.

So for the past month I’ve been fighting a fierce war, which mostly involves a lot of stamping my feet and pouting.

I concluded that I can’t wait for the fruit to ripen on the plants – they get stung long before then. So I started to pick them green, just as they start to blush. That’s no longer working.

I tried harvesting them anyway with a view to cutting around infected flesh. But even the fruit with minor stings (even just on ripening) are well and truly gone by the time they are red enough to cut. These blighters ruin tomatoes – quickly.

I’ve learned my lesson – once the fruit is stung there’s no use keeping it on the plant.

So this evening I went out and discarded all fruit with stings. There was more than 4 kilograms, which would have been much more if I’d let it keep growing until ripe. A couple were extremely large Brandywines – maybe 400g each already. Heartbreaking.

The chooks are getting spoiled – they leave the green ones  on the coop floor until they start to ripen, by which time they are crawling with grubs. Bonus points! Funnily enough they’re not getting through the layer pellets very quickly – I think my eggs are simply tomatoes with added protein, rearranged.

But I did have a plan. I’ve done a lot of reading and concluded that baits and traps are helpful, but won’t prevent losses. What does seem to help however is exclusion.

So I bought these nifty bags. They are made of lightweight mesh, allow plenty of light and airflow, and can be reused for different crops over multiple seasons. Most importantly, they apparently stop the fruit fly.

I bought 10 of them as a start, and bagged whole trusses at a time. It would have been more efficient if I didn’t already have to throw out a significant portion of my crop, but I’m confident that the fruit I have bagged should be safe.

I’m going to see how they go and probably buy some more bags if they are successful. I’m going to need a whole bunch soon to protect my second crop of Anna apples – 14 fruit have set on my dwarf tree already, with many new flowers open now. Not bad for a follow-up crop. I think I will have to thin them, but we all know how good I am at that!

So who else struggles with fruit fly? Any other strategies I should know about? I’m I setting myself up for disappointment?

Tonight I planned Thin-sliced beef with sesame for dinner, but after getting home from work I really couldn’t be arsed. So instead, we had:

Can’t be arsed salad (that won’t stick to your arse)

  • Iceberg Lettuce
  • 1/2 an avocado, cubed.
  • 2 tomatoes, roughly diced
  • Handful of pitted kalamata olives
  • Small tin of Tuna in springwater
  • a few spoonfuls of baby capers
  • A handful of green beans
  • Japanese fat-free sesame salad dressing

Basically, I just grabbed whatever salad-type ingredients I had on hand and chucked them together.

I use this Japanese salad dressing constantly because I LOVE it, and it’s great for P’s diet because it has basically no fat and very low in calories. It’s just a mixture of vinegar, soy, rice wine, honey, and thickeners. There is quite a dose of flavour enhancers thrown in for good measure, but I’ve never been particularly afraid of MSG. In fact, I even add it to my cooking sometimes. I should be ashamed to admit that, shouldn’t I?

Attack of the aphids

9 Mar

Aphid infestation on my radish leaves

I had a few aphids on my radishes. Since they are radishes (and the good bit is underground), I figured I’d just live with them and see if the beneficial insects would control them. That was a mistake – the population has exploded, and is now overtaking the gherkin/cucumber that is growing above them too.

Aphids on my cucumber

I did a bit of a search about organic aphid control, and was convinced that I could control them effectively with a tomato leaf spray. This is basically several cups of chopped up tomato leaves steeped overnight in water, then strained and sprayed over the aphids. I gave it a try, but I don’t think I used enough tomato leaf for the quantity of water, becauase I could almost hear the aphids laughing at me. I came back later with a bit of pyrethrum and sprayed one leaf with it. Those aphids weren’t laughing.

I’ll try again over the weekend with some more tomato leaf spray, but I’m mighty tempted by the pyrethrum.


The rest of the garden is going pretty swimmingly. My first batch of green bush beans are just reaching full production, my silverbeet still looks wonderful and glossy, my tomatoes seem to be resisting the possums and birds, and the edamame soybeans are in full flower and just about to set their pods. My dwarf banana is surging upwards at an amazing rate – I hope to get fruit next summer.

My new garden bed along the front yard is 20% prepared and planted out, and I’ve packed it to the brim with brassicas, various onions and leafy winter crops. Hopefully I’ll get the chance to prepare the rest of the bed over the weekend and get it planted out soon. Can’t wait to get the peas and broad beans happening!

Don’t get cocky halfway through the harvest

21 Feb

I often ponder my favourite foods. I’m a bit of a loony actually, and I often think about it in terms of “which food would I choose if I had to live on one food only for the rest of my life?” Tomatoes would have to be on the short list, along with Gravox pepper sauce. I might have trouble achieving self sufficiency in the latter.

I have been getting some wonderful tomatoes from my three plants. They have been pest-free, delicious and plentiful. I have two cherry truss tomato plants and once mini roma. All F1 hybrids, as seems to be the way with seedlings from Bunnings.

My tomatoes

I have my tomatoes growing in the same place that Ron* has been growing them for years (so much for crop rotation). They are enclosed in a frame with shadecloth on all sides for protection from the sun and predators, but I haven’t been using the shadecloth because I haven’t needed it. You can see that my plants have well and truly outgrown their stakes and are approaching 8 feet tall. I really should pinch out the growing tips, but my climate is frost-free, and I’m greedy.

I have been struggling a bit with a fungal blight, which I have been controlling with an organic fungicide and some tomato dust. Considering the extraordinary humidity this year and the lack of crop rotation, I’m surprised it hasn’t been worse. I plan to plant a green manure crop of bio mustard once the tomatoes have finished, which will clean up the fungal spores in the soil, and hopefully let me plant tomatoes again in this spot in a couple of years.

Possum damage to my tomatoes

Last night I heard possums outside, and didn’t think much of it. This morning though I realised that all my ripe tomatoes were gone, and the ripest of the ones that were left had claw or teeth marks in it. I guess I know now what the shadecloth was for. I should never doubt Ron.

I have now rolled down the shadecloth on either side of the plants, but I have let them grown too high to be enclosed at the top. I’ll see how I go by just enclosing the sides, but I may need to take some drastic action.

* Ron is the man that we bought our house from. He and his wife Margaret were amazing gardeners.