Ficus Alert

If you have a recently acquired variety of Chinese banyan (Ficus microcarpa), including tiger bark, Green Island, Golden Gate, etc., watch out for leaf galls. Here is an article with a picture of a bad case.
http://collier.ifas.ufl.edu/CommHort/CommHortPubs/FicusTreeAttack.PDF
If you have ever dealt with Chinese elm leaf galls, you are familiar with the problem. Regardless of your opinion of insecticides, the only treatment is a systemic. Bayer Tree & Shrub seems to be the only one available in New York State & probably elsewhere. The systemics are only rated for outdoor use. If you must spray during the winter, use the garage, an enclosed porch, or a spare room. After spraying quickly, close the door and leave it for two hours. Don't quote me; I know it is risky. I've been doing it for many years, but rarely.
The article recommends a soil drench with imidocloprid (Bayer's). Has anyone ever tried this on a bonsai?
Iris

Iris,

Thanks for the informational post. I recieved an order of Ficus last month out of Florida that had a few leaves with these bubbles. It appeared as a pod or bubble within the leaf. I removed all the leaves prior to them going in my greenhouse. However, I have not since seen any such leaves, but I will take a closer look.

Thanks,
Abe

I would spray as a precaution. We don't know what the incubation period is.
Iris

bonsaisr wrote:If you have a recently acquired variety of Chinese banyan (Ficus microcarpa), including tiger bark, Green Island, Golden Gate, etc., watch out for leaf galls. Here is an article with a picture of a bad case.
http://collier.ifas.ufl.edu/CommHort/CommHortPubs/FicusTreeAttack.PDF
If you have ever dealt with Chinese elm leaf galls, you are familiar with the problem. Regardless of your opinion of insecticides, the only treatment is a systemic. Bayer Tree & Shrub seems to be the only one available in New York State & probably elsewhere. The systemics are only rated for outdoor use. If you must spray during the winter, use the garage, an enclosed porch, or a spare room. After spraying quickly, close the door and leave it for two hours. Don't quote me; I know it is risky. I've been doing it for many years, but rarely.
The article recommends a soil drench with imadocloprid (Bayer's). Has anyone ever tried this on a bonsai?
Iris

There is a group from a I think Frenso area bonsai club that did quite a bit of testing with the Bayers and after several years and in consultation with Bayer they worked out how to use it for bonsai. For the last 4 years I've been using the Bayers Tree& Shrub on my bonsai every 6 months- 1 tablespoon to a gallon of water and soak the soil.

Thank you for the formulation.
Jim Lewis (and probably Nina) will have something to say. You are forgetting the first rule of pest management. Never spray on a schedule unless you know that a certain pest will arrive every year. Otherwise, never spray unless you see signs of a pest. If you just spray on a schedule, you are only building up pesticide-resistant populations. It is like giving your child an antibiotic every six months whether he is sick or not.
Iris

You're correct about not treating unless necessary. Just to be clear though the Bayer is not sprayed but used as a soil drench. We historically have a problem with borers in pine and prunus species and juniper tip miners as well as termites etc in the collected trees. Since starting this I've had no insect problems except for the ongoing battle to control spider mites- I may think about skipping a treatment here and there though.

Bob Pressler wrote: We historically have a problem with borers in pine and prunus species and juniper tip miners as well as termites etc in the collected trees.

Of course, you are in California. Never pontificate from another planet. But I did want to warn new readers not to treat on a schedule unless they have ongoing problems.

Bob Pressler wrote:
Since starting this I've had no insect problems except for the ongoing battle to control spider mites-

The literature reveals that imidacloprid (Bayer's) actually encourages the proliferation of spider mites, since it kills their parasites without touching the mites. If that is the only systemic available, you have your hands full.
Iris

I used imadocloprid (non-Bayer brand) to help clear up some nasty scale and related issues in my bonsai. Used as a soil drench. Also used it on a large yard maple that had aphids (one of the standard uses). It is supposed to be good for a year after it is taken up into the tree. I would suggest caution in using on flowering species because it is fairly toxic to bees and similar beneficial species.

bonsaisr wrote:

Bob Pressler wrote: We historically have a problem with borers in pine and prunus species and juniper tip miners as well as termites etc in the collected trees.

Of course, you are in California. Never pontificate from another planet. But I did want to warn new readers not to treat on a schedule unless they have ongoing problems.

Bob Pressler wrote:
Since starting this I've had no insect problems except for the ongoing battle to control spider mites-

The literature reveals that imidacloprid (Bayer's) actually encourages the proliferation of spider mites, since it kills their parasites without touching the mites. If that is the only systemic available, you have your hands full.
Iris

Now that funny because Bayer also just happens to make a pretty good miticide. There are hundreds of Itailian cypress in the area which are just big spider mite breeding factories. I use several different sprays to deal with them.

Would anyone know if Neem Oil has been tested on this form of leaf gall? I have had great success using this on my tropicals with other pests.

Thanks,
Abe

Who does PR for Neem oil -- especially in the bonsai community?

Never in my life have I seen a pesticide touted so heavily -- at least not since DDT.

Jim,

Not sure I understand your comment on Neem Oil. I am not a PR for the product nor a salesmen of the product, just wanted to share some informaton that may aid other Bonsai enthusiasts. I have had much success with its use in the past, other than its smell. Its a natural product and an excellent non-chemical choice. It also acts as a nice leaf shine.
Below is a study conducted by Cornell University and its effective uses, etc.

http://web.pppmb.cals.cornell.edu/resourceguide/mfs/08neem.php

Abe

Neem oil may be very good for certain applications, but it is primarily a contact spray. It only hits what is outside the leaf. The wasp larva is INSIDE the leaf. It can only be killed by a systemic insecticide, a chemical that is taken up by the plant and transferred to inside tissues. The article mentions that neem products may be taken up systemically, but it is very vague. I would like to see results of testing and whether it is effective on any particular insect. I would prefer to use a proven pesticide.
Iris

Abe . . . I wasn't saying you were PR for neem, but I wondered who was since he/she seems to be doing a helluva job promoting the stuff as the kill-all for every bonsai ill.

Sorry if you misunderstood.

I used the recommended soil drench with imidacloprid and have not seen any further evidence of leaf galls. The wasps are unlikely to fly into the house in the winter, but we need to be vigilant during the summer when our figs are outdoors. Tiger bark, ginseng ficus, & other F. microcarpa varieties are so popular these days, your next door neighbor could have an infestation. When I had a large 'Seiju,' I used to get leaf gall mites every summer, even though there were no bonsai (that I knew of) for miles around. However, there were Siberian elms all over, which may have been the vector.
Iris

Oh Iris, that is good to know!

I recently purchased a 'Seiju' elm just a couple months ago, and Siberian elms are all around our house and neighborhood. We rarely see leave gall on them here though, but it does occur. This will be something I will be mindful of with my new 'Seiju'.