Pest ID

[mikejphuket]

Looking for help with this stuff. Is getting on sour sop, avocado and durian trees. Seems able to suck the water out of branches eventually killing them. What is it and how to eliminate without nasty chemicals? Thx 

[drtreelove]

It appears to be "soft-bodied scale", a sucking insect pest.  But many of the adults look like they have been parasitized, holes in the body and drying up. So you may have mini-wasps ovipositing and working on your behalf.

 

It looks like there are a lot of crawlers present, hordes of smaller white nymphs looking for a spot to insert piercing sucking mouth parts and settle in for the duration. They will not be subject to the parasitoid yet. A summer oil, 1% hort oil will smother them and not burn foliage like 2% dormant spray might. Insecticidal soap will kill them on contact. Maybe wood vinegar, but I haven't used it.

 

The adult scale insects are protected by a waxy coating, something like their cousins mealybugs, so contact sprays are not effective, only in the "crawler" or immature stage. Neem or other botanicals are good as repellent, for prevention but not for this kind of advanced activity.  Hosing them off doesn't work as well with scale as it does with mealybugs.

 

Soft bodied scale are often predominant in more shaded areas of the foliar canopy, but that can vary. If so, you can possibly prune out the most infested branches to cut down on numbers, and thin the canopy for more air and light circulation. I have found this very effective with citrus.

 

Avoid high NPK chemical fertilizers, especially with Nitrogen value over 10%, which are a magnet for pests. Use slow release, COF (complete organic fertilizer) and build soil organic matter and humus. Good soil fertility and water management enhances plant resistance to pests and diseases. Unfortunately the new generation mineralized COF's with beneficial microbial inoculants, that are so widely available in the US, Europe and Australia now, haven't caught on in Thailand. So you have to try to put together your own program.  Good compost, aged manure, mulching and EM or compost tea may be the best you can do.  Bat guano, worm castings and other organic fertilizer are available.

 

Now you know what can happen, and the early spring timing, next year you can be better prepared to start a preventive program and early intervention. Start close inspections/monitoring daily or at least weekly in January-February. Look for scale crawlers, aphids, caterpillars.

 

Hope that helps, Don

 

 

[mikejphuket]

Perfect !! Thank you so much !! I gave in to my gardener and let him apply 15-15-15 chemical fertilizer instead of compost that i have been using for years. Seems to be the trigger.

I am unfamiliar with insecticidal soap, is it available in LOS?

Thanks again, your info is highly appreciated. I am not much of a green thumb, but do enjoying eating fruit from my own trees. ????

[drtreelove]

I have seen insecticidal soap at a specialty organic farm shop, but its not widely available. You can make your own. Here is one article.  Be sure to note the type of soap recommended. And even though it is "organic" program compatible, protect your eyes and use conservatively, target active pests only, don't spra the whole frikkin garden. ????

https://www.hortmag.com/weekly-tips/pests-diseases/mix-your-own-insecticidal-soap-for-garden-pests

Standard personal protection, even with bio-pesticides, is long sleeve shirt and long pants, shoes/boots and socks, chemical resistant gloves and eye protection. Shower after application.

 

Wood vinegar is a more widely available organic program pesticide here. My local Home Pro had two brands on the shelf in the garden section last week when I was buying molasses to brew some EM. In high concentrations it a weed killer, so take note of mixing rates and use conservatively.

 

 

 

 

[drtreelove]

Here's a couple of other new generation biopesticide options that are now available in Thailand:

Through the links to US sources you can read the product descriptions. And I will attached some pics of products that I took in an ag shop in Chiang Mai.

For the foliar pests I would go with the Beauveria, for soil and compost grubs including coconut rhinoceros beetle, I would use the Metarhizium (green muscaridine fungus).

This is a new and rapidly developing product catergory. Those who use "pesticides" as a dirty word across the board should take note and get educated in new environmentally friendly and sustaninable biopesticide technologies being developed due to popular demand and a huge potential market.

 

Beauveria bassiana, an entomopathogenic fungus that attacks a long-list of troublesome crop pests (not plants) like aphids, thrips, whitefly, spider mites, mealybugs, root aphids and more!

https://www.planetnatural.com/product/botanigard-es-insecticide/

https://www.domyown.com/bioceres-wp-p-17144.html

Metarhizium anisopliae is a naturally occurring fungus — not genetically modified — found in soils worldwide. Once the spores come in contact with susceptible insects they penetrate the cuticle or exoskeleton and begin to grow inside, causing the insect to die.

https://www.planetnatural.com/product/met52-ec/

[drtreelove]

Mike thanks for revealing the bit about the gardener and the 15-15-15, it confirms my suspicion. It is something that many growers just don't get, especially those who are working with old information and are not keeping up on the new agriculture. Because it's deceiving, high NPK gets good growth response, but at the expense of throwing off the soil mineral and biological balance, depleting other nutrients that aren't recognized and are not replenished, but which are important for plant resistance to pests and disease. The high salts dessicate roots, which increases water stress, which invites pest pressure.  The harsh chemicals negatively affect beneficial soil biology that is so important for assimilation of nutrients and defense against soil borne pathogens. You think green is good and you're doing something right, and it's cheap, but then you wake up and your plants are covered in pests. And neem doesn't work and you scramble to find something stronger to kill them. Its a viscious cycle, and the reason for so much unneccesary pesticide use and food contamination.

 

It's not just my idea, here is an interview that demonstrates state-of-the-art agronomy and the preventive approach that focuses on soil health as the first line of management:

 

"There is no doubt about it. The mismanagement of nitrogen is the biggest player. If you want pests and disease, just start pouring on the nitrogen. Growers put too much importance on this mineral. My most successful growers focus upon having their nitrogen as low as possible."

https://blog.nutri-tech.com.au/interview-with-a-master-agronomist-stephan-timmermans/

 

[mikejphuket]

Thank you VERY much !!