Nematodes for apple maggot control?

Hi there,

We have 4 gorgeous mature apple trees in our yard. They're beautiful and produce like gangbusters, but the oldest one in particular is really hit hard every year with apple maggot, and to a lesser extent with codling moth. By harvest time, its apples are nearly entirely inedible.

We're working to break their cycles picking up the fallen fruit, and had terrific inroads last year with homemade milk jug lures we made from molasses, vinegar and ammonia.

Now that we're gearing up for spring, I'd like to do some early management as they emerge from the soil, before they reach the canopy and fruit.

Has anyone here applied nematodes under their trees? I've read some extension office stuff on using them as controls, but haven't seen much info one way or the other about how using them as a biological control affects other soil organisms. I like beneficial insects. I don't want to bumble my way into creating a bigger problem than I'm trying to solve.

Anyone with experience using nematode products?

Thanks,

Carla

You can make a trap with red balls covered in vaseline or some other sticky substance. However longer term I would encourage the predators like predatory wasps, lacewings etc. They like the small flowers of plants like fennel, yarrow, angelica etc.

If you hit the apple maggot with nematodes they are usually species specific you might find you have an issue with another pest in a different year. However if you plant the right plants and attract the beneficial insects they tend to snack on a range of other creatures you might not want too.

Thanks. I'll give companion planting a try again. We put in some hyssop, borage and mints last year, but they got pretty leggy and weak from all the shade. Maybe plant them out closer to the drip line where they'll get more sun, and add in the smaller flowered plants. Great tip!

Carla

If they are getting very shaded out you might want to consider pruning the apple trees, if your northern hemisphere and it is not likely to freeze too badly where you are you can start it now. The increase in airflow and sun penetration from the pruning always helps the quality of the fruit especially if you are in a damper climate like me.

The beneficial nematodes I'm familiar with aren't very species specific. They'll basically go after any species with a life stage that involves being a grub in the ground. They're a really favorite here to counter fire ants, fleas, and lawn grubs.

Edit: Actually, this company specifically names apple grubs. I'd contact the company with any questions or concerns. I don't know which species we've used as it helped with every issue listed under a specific species. We just pick up what the local garden centers carry.

Looks like I got that sort of wrong however nematodes I have used in the past didn't seem to offer significant protection longer than the length stated on the packet so I would argue attracting beneficial predators is still a better investment in both time and money. Also your predators (you are attarcting more than one type) will attack other apple tree pests like aphids etc too.

Henry Jabel wrote:If they are getting very shaded out you might want to consider pruning the apple trees, if your northern hemisphere and it is not likely to freeze too badly where you are you can start it now.

Which leads to a pruning question, if course! So the main tree is probably about 30 years old, I'd guess. (We've only had the property for four years.)  The tree has mostly western exposure, with some dappled afternoon light later in the afternoon once the sun clears the house.  I've been pruning for about 2 years, the first year probably too aggressively. So now we have picked of 10' tall water sprouts with 2" diameters.

Reading pruning books, most recommend a multi-year regimen to keep the sprouting to a minimum. So I'm thinking about taking the top right main leader down at the fork for 2017. That branch probably has a 12-14" diameter, so I'm nervous taking it out will harm the tree.

I'd like to bring the canopy down for easier harvest, but the other issue we have is that the drip line probably has a 12' radius sticking out into the side yard. That area is the only access we have to the back yard, so we also need head clearance.

It's a lovely tree planted in a less than ideal spot. I'm hoping to keep it, rehab it to a more manageable size, and break the pest cycle. Pruning/thinning, companion planting, and possibly nematodes along with the molasses lures were my thoughts. I just don't want to kill the tree!

Carla Williams wrote:

Henry Jabel wrote:If they are getting very shaded out you might want to consider pruning the apple trees, if your northern hemisphere and it is not likely to freeze too badly where you are you can start it now.

Which leads to a pruning question, if course! So the main tree is probably about 30 years old, I'd guess. (We've only had the property for four years.)  The tree has mostly western exposure, with some dappled afternoon light later in the afternoon once the sun clears the house.  I've been pruning for about 2 years, the first year probably too aggressively. So now we have picked of 10' tall water sprouts with 2" diameters.

Reading pruning books, most recommend a multi-year regimen to keep the sprouting to a minimum. So I'm thinking about taking the top right main leader down at the fork for 2017. That branch probably has a 12-14" diameter, so I'm nervous taking it out will harm the tree.

I'd like to bring the canopy down for easier harvest, but the other issue we have is that the drip line probably has a 12' radius sticking out into the side yard. That area is the only access we have to the back yard, so we also need head clearance.

It's a lovely tree planted in a less than ideal spot. I'm hoping to keep it, rehab it to a more manageable size, and break the pest cycle. Pruning/thinning, companion planting, and possibly nematodes along with the molasses lures were my thoughts. I just don't want to kill the tree!

Which fork are you talking about? Either way you should be fine if you are only taking a 3rd out a year. Its always hard to see what is going on from a photo but from looking at it I would prune it.