bugs

[sbb87]

hello everyone. I hope someone can help. I was watering today and I noticed some sort of teeny teeny bugs in the medium of several orchids. i am so upset. I have never had a bug of any kind before and i have plants for several years now. The bark medium is fairly new not broken down. They are almost microscopic. in the medium only. I was at the orchid show in NYC in april. Bought 3 new plants. kept them in isolation for 8 weeks. everything seemed fine. Now several of my orchids have these bugs. I can't seem to find what they are. They are crawling in the medium, not flying. I removed the plants. any ideas what these are? what do I do? please help.
thanks
sb

[captripppp]

I'm not really sure what kind of bugs they could be, but I can tell you what I do to avoid bugs, aphids, and the like. I use neem oil, which is a natural pesticide derived from the neem tree in africa. Neem oil is systemic in the plants, meaning that it will build up in the plants so fewer and fewer applications are necessary. Right now I only spray my plants once every other month, and I have no bug problems. The way neem oil works is by causing the bugs that consume a part of a plant or sap to become sterile. You can search neem oil, and find out some good info on it. There have been quite a few studies on neem oil, and some of the findings are pretty neat. In one test they found that plant treated with neem under a dome with insects, that the insects would rather starve to death rather than eat from the plant. Also neem oil is nontoxic, so you don't have to worry about wearing a respirator, or gloves. It just smells like onion soup! Hope I could help. Aaron

[Lucifer]

Hello
This is my first post and my first visit to this forum. I was going to lurk a bit before I joined, but the above response I couldn't ignore.

Please read my responses in red.

Originally Posted by captripppp

I'm not really sure what kind of bugs they could be, but I can tell you what I do to avoid bugs, aphids, and the like. I use neem oil, which is a natural pesticide derived from the neem tree in africa.

The tree is from Asia

Neem oil is systemic in the plants, meaning that it will build up in the plants so fewer and fewer applications are necessary.

Neem oil isn't systemic. It works by making contact with the insect or by the insect ingesting residual neem oil on the plants. Also, your definition of systemic is incorrect. Systemic pesticides are capable of being translocated within the plant tissue to parts of the plant. They don't build up in plants, they actually break down over a period time depending on the chemical.

Right now I only spray my plants once every other month, and I have no bug problems.

Profolactic use of neem oil is a good idea.

The way neem oil works is by causing the bugs that consume a part of a plant or sap to become sterile.

Neem oil works in a few ways, but not in the way as stated above. The most common way is that it affects the exoskeliton of the insect. Another way is discouraging the insects from laying eggs on the plants.

You can search neem oil, and find out some good info on it. There have been quite a few studies on neem oil, and some of the findings are pretty neat.

There are plenty of great sites on the internet full of information on Neem and neem oil. I suggest you try to find one put out by the Extension Services of an University. They tend to have the most reliable information. Heres one put out by Cornell University:

nysaes.cornell.edu/pp/resourceguide/mfs/08neem.php


Also neem oil is nontoxic, so you don't have to worry about wearing a respirator, or gloves. It just smells like onion soup! Hope I could help. Aaron

Dispite the non toxic claim, It is advised to still take procautions, gloves, eye protection and ventalation.

I apologize If my first post here seems harsh, but I don't want to see new growers discouraged by problem plants. Neem oil is a great product, but it does have limitations.

To, Sbb87: Could be Fungas Gnat larva. Won't cause a problem to the orchids, but are annoying when they turn into flys. Buy a Sundew to catch the flies.

[captripppp]

My apologies neem is from India, but as for the rest you may visit neem foundation .org, and look under organic gardening. The things that I have stated previously can be backed up there
(i.e. steralization of adult insects), as well as some of things said by lucifer. As for neem being systemic; I must have been ill advised by many of my friends, and reapected growers in my area. My apologies. Aaron

[Lucifer]

I accept your apology.

Don't hold it against your respected grower friends that they have been telling you white lies about Neem oil. Its easy to believe some of the stuff printed on the web, especially when you really really want to believe it to be true...

The good thing about information gathered from publications put out by a University Extension Services is that they will back up the info with citations from scientific studies (usually) published in peer reviewed journals. The web site you directed us too contained sporatic citations and no information as to the journal they are from. I did get tired of reading it, and didn't finsh the whole page, but I think I got the jist of it.

Neem oil good, but be realistic its isn't a miracle cure all.

I leave you with one last thought, If neem oil can sterilize an insect, how wise is it to spray it with no safety equipment?

[Cynthia, Prescott, AZ]

Just to take a bit of the glow off neem oil, it is almost impossible to use it in a heat wave. The plant must be kept out of the sun and heat for a while after use, or one will find strange mottling of the folage. I have lots of this in my green house and am having to tone down my use of neem oil. For a few real problem plants, they get carried off to my nice cool basement for treatment and recouperation of a few days. But the other 700 plants aren't going anywhere. So I am currently experimenting with a few systemics. Cynthia, Prescott, AZ

[mintyfresh]

Those "teeny teeny bugs" sound like mites. I have observed mites in orchid potting mix before, and I just repotted my orchid (and threw the old, infested mix in the trash). The mites I saw were orangish, but there are many species of mites and they come in many different colors. If the "bugs" are fungus gnat larvae, they would be white maggots with black heads.

[sbb87]

Thank you all for the imput
Cynthia: thanks for the post and e-mail.
Lucifer: no harm, no foul. I understood what captrippp (thanks for the info on neem oil) was trying to say by the use of the word systemic though not exactly the true meaning of the word. You have some good points both about the internet and about toxicity....It was interesting about the neem oil. I too respect the cornell people. FYI: prophylactic.
Mintyfresh: Yes, yes yes!! Thanks. I believe you are right. I looked under the microscope and these are definitely not gnats. 6 pairs of legs and mouth parts. At first I thought some sort of lice but mites, yes AND this occurred shortly after I repotted and they came from the deep within the media and not atop it. I soaked the media too long before repotting. i knew this was a mistake. I am pretty sure this and/or maybe bad media is the reason as it is the only thing I did differently than previous times. Rule #1: Never change your first answer.... So I bought new media and will repot. Do I need to wash the plants in anyththing before repotting eg mild detergent?
Again thanks to you all for the imput and valuable discourse.
sb

[Cynthia, Prescott, AZ]

I have been reading up on neem oil. The hydrophyllic extract of neem that I have been using successfully is missing a good deal of the active chemicals by being extracted. Will have to get some of the pure stuff and experiment with it. I know how my plants react to the extract, but the other is still a mystery to me. Don't want to put my 700 plants at risk. Cynthia