Question: I have 30 crepe myrtle trees that are infested with the ambrosia beetle. I just discovered them this spring, and my trees are still very healthy looking. If I use the Orange TKO and mineral oil treatment… do I paint the entire trunk of the infested tree or just the toothpicks protruding from the tree where the beetle made the hole? Please give me more direction for saving my trees.

Answer: The fact that your trees already have the ambrosia beetle (how did you know this? Did you get an arborist? If so what did he say?), you maybe already too late. You must realize that this did not happen overnight and the beetles have discovered a perfect environment to lay their eggs and the fungus the use to feed their kids.

There are many things you can do to help these trees. They may look healthy to you, but the beetle knows different. The trees are stressed out from something. You do not mention where in the world you are at so I will be guessing the following: type of soil, amount of rain, temperature, underground watering as well as what you have been feeding the trees.

The stress usually comes from soil damage. The trees need over 72 trace minerals, more like 96 trace minerals. Miss just one and you will get pests coming around. Miss a few more trace minerals and it only gets worse. The ambrosia beetle requires that the tree be deficient in exotic trace minerals. These are used by the tree to achieve a high Brix reading. Trees with a Brix reading at certain levels will not get attacked by a specific pest. Each pest has their own Brix range but they usually all fall within a certain range. While Brix is a measurement of sugar levels, it is also a measurement of mineral levels. The is a tool in determining what stresses are affecting the tree(s). Best used as a preventative tool. It allows one to see in advance any problems coming their way and avoid it.

So what can you do? First, realize that the long-term solution is better soil care. Since you do not mention using compost or rock dust around these trees, I would start there. Apply an organic fertilizer /compost mix with micro and microbes to begin helping the soil.  I would add rock dust to the mix. Get a rock dust blend to make sure you have a wide range of minerals. The trees' roots are probably damaged and will need time to start working again, so the short-term solution is to foliar spray your trees as well as the soil.

Foliar spraying means applying nutrition directly to the leaves and trunk of the tree. It will immediately absorb and assimilate the food. I would start at first with a mineral-rich compost tea. It is essential that the mineral sources one that has a broad blend of trace minerals. Try Sea 90. Get a person that has a 100-gallon sprayer that is willing to spray it for you and hasn’t been using chemicals. I would add the Sea-90 to the compost tea. So this person should also know how to make compost and or compost tea. The compost must also be made correctly with all the microbes and minerals. By spraying the tree and trunk, you will not only be getting minerals into the tree, but you will also be spraying the beetles, etc. with the microbes and this will positively affect the beetles. Should be done at min twice a month but I would do it every week for a few months.

You should be applying rock dust, compost and then mulching over it. Should be done twice per year.

Concerning watering:

You do not mention how these trees are getting watered? I am betting either they are not getting enough water or too much water since water plays a vital role in the transmission of minerals and nutrition throughout the tree.  Usually, if you are overwatering, you are destroying the microbial balance in the soil which then causes stress and trace mineral deficiency in the trees.

These trees require a proper deep watering once or maybe twice month depending on soil conditions. I would place a drip system under the trees. Provide them with their own timer program. Do not water like you are watering the lawn.  Drip should be two gals per hours drip head, place in two circles, one about midway from trunk to drip then, the second around the drip line. A third line can be placed 5 feet out from the drip line. Water about 1 hour per month. Watch and see if the water runs and is not soaked into the soil.

I am guessing these trees are near a lawn? Lawns that are not fertilized organically are high, and high nitrogen inhibits the absorption of trace minerals especially the exotic ones.

Concerning using the Orange TKO and mineral oil treatment:  will work only if the tree is starting to get foliar spraying and have the stress reduced. You can get a one-gallon sprayer. Fill 1/2 with OTKO and 1/2 with mineral oil. Spray directly into any holes. The mist the entire tank from the ground up to 2 feet. Another spray is made from Nitron-A35 which is an enzyme. Add 1 cup to 1 gal water, spray directly into their tunnels. Repeat once a week. Something else you can use is called Wood Vinegar. I would use two tablespoons per gallon water and spray the trunks and holes. Try https://verdilife.com/  as they are the only source of this in the USA for now. You can also make a strong compost tea and spray the trunks daily for a few weeks.

This should get you started. Any questions? Email me at andylopez@invisiblegardener.com

andy Lopez (yes, I use little 'a') aka, the Invisible Gardener