Trees Stripped Bare By Insects Overnight

[wontok]

We have many young trees on our plot here in Roi Et. Most are about one and a half years old and are doing well, but recently some have been attacked by flying insects that have stripped them bare overnight. Each morning we have found one or more trees completely without leaves. It's the more decorative tress with softer leaves that are getting eaten, such as Ton Beep, and Ton Care (excuse spelling), while mangos and neem and the like are untouched. This first happened a month or so ago, and last night the first of them was attacked for a second time - all its newly regrown leaves removed in one night. We're not sure how much of this our trees can stand - we have tried putting lights out to attract them away from the trees but without success, and the trees are too big to spray or net. We have seen small (maybe 5mm long), dark brown flying insects on the leafless twigs afterwards, often in pairs, apparently mating. Does anyone have any ideas what these little buggers are and/or what we might do about them?

[surayu]

termites?

http://ohioline.osu.edu/hyg-fact/2000/2092.html

[soidog2]

There are quite a lot of possibilities and they all love succulent young leaves

If you could post a picture of the offenders it would help.

Meanwhile spray a mixture of cypermethrin & abamectin, it will get rid of your bugs.

Follow instructions, wear protection, spray early morning to give the chemical a chance to settle if it rains in the afternoon.

Good luck

[drtreelove]

This is the time of year for a lot of insect activity. I don't have a direct answer, but I would be interested to see some photos of the damage and the site, as well as the insects that you suspect. I don't know the plant pests in your area, but from my experience it would be unusual for a small adult insect to defoliate a tree overnight. The usual suspects in tree defoliation are larva (catepillars/worms) of moths or beetles. Elm leaf beetle, oak moth catepillar, tussok moth are examples of what I had to deal with in California. Some have stages of development called instars, the first instars are smaller and cannot chew completely through the leaf but the eat the surfaces and 'skeletonize' the leaves, leaving the veins and heavier margins; as they mature into larger size instars they can chew the entire leaf thickness. Many moth catepillars, when finished feeding and ready to pupate, decend from the tree on threads, like a single strand spider web. Have you seen any of this type of activity?

Soidog2 has recommended a killer combination to spray, if you determine that it is a leaf feeding insect and currently present for contact spraying. Cypermethrin and abemectin are among the least toxic alternatives available in a chemical spray program, but not organic.

Cypermethrin is a pyrethroid and a contact spray with some residual barrier protection (for a few days) without being a long lasting pervasive toxin in the environment from my understanding. It appears to be the most common general purpose insecticide used by many pest control companies in Thailand. It's the primary active ingredient in Chaindrite products and others. But this chemical kills beneficial insects, natural predators of insect pests too, and therefore does not fit the strict organic model. So use as a last resort and only with an identifiable target.

Abemectin is a stomach poison, so it has to be injested by the pest; no point in spraying it on a tree that has already been defoliated. If sprayed on the young foliage of a susceptible tree it would be absorbed and offer some longer lasting protection. It's best to know the insect pest that you are dealing with and their life cycle, so identification is first.

Usually a relatively healthy tree can take one or two complete defoliations and recover after the pest has completed its life cycle and stopped repeated feedings. More than that and the loss of foliage for an entire season and therefore loss of photosynthesis of sugars will create dangerous stress. If the tree is vigorous it will leaf out again and resume healthy growth. Some pests have two or more emergences in a season; meaning the first cycle completes in pupation, then adults emerge and lay eggs for a second hatch. That is a dangerous pest and anticipation of the second hatch is important for timing of control. That's why identification is important.

If you have a stealth, hungry, rapid defoliator then you may not be able to anticipate and provide organic methods of control. The organic methods available for pest control have been discussed before in this forum and include an integrated pest management approach, where you respect the natural ecosystem and biological controls that may already be in place. If the pest that defoliated your trees is gone now, it could be that it completed it's life cycle, or the birds or other biological agents have had a feeding frenzy too and the situation is under control. Another organic method is to spray with neem extract, a repellent and reproductive disruptor, or other botanical formulas. These usually require repeated applications, sometimes weekly to be effective, depending on what the target pest is. The IPM and organic model does not permit broad spectrum pesticide application, especially for an undetermined pest problem.

Termites, to my knowledge do not feed on foliage, only on dry wood and bark. They can damage a tree, but not likely in the way that you are describing. Unless they have debarked the root collar or trunk and destroyed the protective function of the bark for the growing layer of cambium underneath. don

[wontok]

Thanks for your replies. The first time round five trees were stripped over three nights. All regrew well. It was the second attack on one of them that prompted me to seek help. That happened a few days ago and so far the other trees are OK. I attach here pictures of one of the regrown trees and a close up of the bare twigs now on the tree that has been attacked twice. You can't see it on the photo but it is just beginning to grow a third set of leaves. Also one of the whole bare tree - complete with (now unoccupied) birds nest! The bare tree looked exactly like the leafed one at 11pm one evening and was leafless when I got up about 5.30am! The trees pictured are Ton Beep (indian cork trees, I think is their English name)

The trees are in our large garden, but only a few metres from the house. The land around them is covered with Malaysian grass and there are other common garden trees and shrubs, as well as mangos, bananas and neem trees within twenty metres.

The trees are all about 4-5m tall and as you can see the damage is severe - I have found no sign of pieces of leaves on the ground in the morning, but I have seen a large number of what looks like small drops of faeces on the ground. My camera does not have the capacity to photo the insects, but I am not convinced that those I described in my first email are in fact responsible as I have seen some of them on other trees and shrubs which are not damaged. We do have a termite problem, but till now that has been limited to occasional forays up the tree trunk, with maybe some minor nibbling at the tree bark. I have also been wondering about something that lives in the ground near the tree (eg a caterpillar or similar), and climbs up the trunk at night to eat everything, but have seen no evidence of this, or any caterpillars/grubs (excuse the technical term) hanging by threads. We've tried spraying (but it's hard on such tall trees) leaving the lights on at night, and there has been no further damage this week, but the trouble is we don't know when it's going to happen, so we can't tell if our precautions have been effective. Staying up all night waiting is not really an option! I'm going to put some ant powder round the base of each tree to try to stop climbing nasties if that's what they are, but if they are flying insects I think we will have to leave the trees to their fate and if they die plant something tougher next time!

Thank you all for your replies - any further suggestions/solutions will be very welcome.

[soidog2]

Thanks for your replies. The first time round five trees were stripped over three nights. All regrew well. It was the second attack on one of them that prompted me to seek help. That happened a few days ago and so far the other trees are OK. I attach here pictures of one of the regrown trees and a close up of the bare twigs now on the tree that has been attacked twice. You can't see it on the photo but it is just beginning to grow a third set of leaves. Also one of the whole bare tree - complete with (now unoccupied) birds nest! The bare tree looked exactly like the leafed one at 11pm one evening and was leafless when I got up about 5.30am! The trees pictured are Ton Beep (indian cork trees, I think is their English name)

The trees are in our large garden, but only a few metres from the house. The land around them is covered with Malaysian grass and there are other common garden trees and shrubs, as well as mangos, bananas and neem trees within twenty metres.

The trees are all about 4-5m tall and as you can see the damage is severe - I have found no sign of pieces of leaves on the ground in the morning, but I have seen a large number of what looks like small drops of faeces on the ground. My camera does not have the capacity to photo the insects, but I am not convinced that those I described in my first email are in fact responsible as I have seen some of them on other trees and shrubs which are not damaged. We do have a termite problem, but till now that has been limited to occasional forays up the tree trunk, with maybe some minor nibbling at the tree bark. I have also been wondering about something that lives in the ground near the tree (eg a caterpillar or similar), and climbs up the trunk at night to eat everything, but have seen no evidence of this, or any caterpillars/grubs (excuse the technical term) hanging by threads. We've tried spraying (but it's hard on such tall trees) leaving the lights on at night, and there has been no further damage this week, but the trouble is we don't know when it's going to happen, so we can't tell if our precautions have been effective. Staying up all night waiting is not really an option! I'm going to put some ant powder round the base of each tree to try to stop climbing nasties if that's what they are, but if they are flying insects I think we will have to leave the trees to their fate and if they die plant something tougher next time!

Thank you all for your replies - any further suggestions/solutions will be very welcome.

The insects ( Beatles ), are they slow moving, you almost can grab them ? with males & females mating ? Male is bright green , female a pale brown. All about 10/12 mm. in length.

Look carefully & report .

This what I suspect, left uncontrolled they will defoliate just about all young leaves.

You need to hire or get a power spray to reach the top of your trees, despite being inorganic, follow my earlier post to get rid of them immediately.

Organic care is possible but not for immediate relief, you need to plan long term, adjust your plantings with beneficial species , natural predators and so on.

Good Luck

best

[drtreelove]

Although I appreciate Soidogs pesticide recommendation as one way to handle an aggressive and severely damaging pest infestation, this is the organic forum so I feel responsible to try to offer a solution that is in line with this approach; for the OP maybe, but also for others who may read this and be interested in strict organic methods.

So one thing to consider, is that this problem may be almost past already. Few insect pests continue indefinitely. The defoliation is unsightly and could be stressing the trees considerably, but one or two defoliations is usually nothing to panic about for a non-crop healthy tree. If you don't have spray equipment or for any reason cannot hire it, then let them feed and let the natural predators find the pest and build up their own population. IPM (integrated pest management) considers patience and tolerance of a limited amount of pest activity to be an important component of IPM methods.

It looks like these trees are close to the house and maybe even in the driveway area. If there is pavement in the root zone then maybe the trees were already in a stressed condition and susceptible to attack. Grass in the root zone of trees can deplete nutrients and compete for available water, so this could be a susceptibility factor also. Spread organic fertilizer and otherwise create more optimum conditions and then even if your trees are attacked, they can respond and refoliate quickly after the attack. Self produced natural pest repellents are part of a healthy tree defense biochemical arsenal. On the other hand, excessive fertilization can create susceptibility too. Raking up the leaves under trees deprives the root zone of mulch which is vital for insulation, moisture retention and decomposing organic matter for the soil and soil micro organisms.

And something to consider, the defoliation can be Nature's way to prevent excessive transpiration and dehydration in drought stress years. And those little poop pellets that are covering the ground after the pest feeding, are a natural fertilizer source. This is sometimes a good thing, combination of anti transpiration and renewed soil fertility.

If the feeding goes on and you feel control is necessary and you can get spray equipment, organic/botanical repellents such as neem and lemongrass or contact sprays such as pyrethrin can be effective if you can determine what insect it is and their method of operation.

The pictures are of a product I have not used myself, but a friend uses it and reports good results. If you spray, use a spreader-sticker for better coverage and residual activity.

If it is an adult beetle or weevil, they are probably flying in from whereever they harbor during the day. If it is a caterpillar, they probably are on the underside of the leaves somewhere, or in rolled up leaves, or in the grass, soil or rocks on the ground from where they crawl up at night to feed. If the later is the case, then your ground treatment or a 'tanglefoot' type of barrier on the stem could help.

[teletiger]

I had this recently with rose bushes. Go out at night with a good torch. All will be revealed.

For our roses it was a small dun coloured beetle. One spray did the trick.

Regards.

[wontok]

Thanks once again for your advice, guys. This update has taken a while because there was nothing to report. We came up against many linguistic and logistic hurdles to the high power spray suggestion, and in the end opted for inaction, after being advised by our local treee supplier that the season for all this mayhem was now over. So we sat back and watched our trees regrow their leaves - until a couple of nights ago when the little buggers returned in large numbers. We noticed a lot of beetles stuck in our fly screens just after dark and I went out to check the trees. I wish I'd taken a photo - there were hundreds of them all over one tree - bugs on top of bugs on top of bugs. The tree they had chosen was completely submerged under thousands of them. We turned all the outside lights on and I shook the tree hard - clouds of them took off and flew to the lights where we were able to catch literally hundreds of them. The neighbours were delighted with an unexpected delicacy for dinner and the tree escaped relatively unscathed. Here's a picture of some of them just before they were turned into dinner.... Sorry about the quality but I think you can see what they are.

We are told they are called "meng liam" (shiny insects) or "chinoon noi" (little bugs)and that they will keep coming until rice planting is finished. The dark coloured ones in the photo are about 2cm long. The bigger green ones are said locally to be the parents of the small ones...... Apparently they all live in holes in the ground and return there by about 9pm..... Certainly they had all disappeared by that time.

They returned the next night, and again last night, but in far fewer numbers each time and so were much easier to deal with. All these nights have been dead calm and I wonder if they stay away when the wind is up?

Looks like we'll be keeping guard on the trees for the next few weeks and hopefully they'll survive this.

Thanks again for your interest and advice

wontok

[soidog2]

Thanks once again for your advice, guys. This update has taken a while because there was nothing to report. We came up against many linguistic and logistic hurdles to the high power spray suggestion, and in the end opted for inaction, after being advised by our local treee supplier that the season for all this mayhem was now over. So we sat back and watched our trees regrow their leaves - until a couple of nights ago when the little buggers returned in large numbers. We noticed a lot of beetles stuck in our fly screens just after dark and I went out to check the trees. I wish I'd taken a photo - there were hundreds of them all over one tree - bugs on top of bugs on top of bugs. The tree they had chosen was completely submerged under thousands of them. We turned all the outside lights on and I shook the tree hard - clouds of them took off and flew to the lights where we were able to catch literally hundreds of them. The neighbours were delighted with an unexpected delicacy for dinner and the tree escaped relatively unscathed. Here's a picture of some of them just before they were turned into dinner.... Sorry about the quality but I think you can see what they are.

We are told they are called "meng liam" (shiny insects) or "chinoon noi" (little bugs)and that they will keep coming until rice planting is finished. The dark coloured ones in the photo are about 2cm long. The bigger green ones are said locally to be the parents of the small ones...... Apparently they all live in holes in the ground and return there by about 9pm..... Certainly they had all disappeared by that time.

They returned the next night, and again last night, but in far fewer numbers each time and so were much easier to deal with. All these nights have been dead calm and I wonder if they stay away when the wind is up?

Looks like we'll be keeping guard on the trees for the next few weeks and hopefully they'll survive this.

Thanks again for your interest and advice

wontok

When in Rome, do like the Romans do.

The most harmless and productive option is :

Somewhere near your trees, set up a large tub filled with about two inches of water.

Go to your local hardware store and buy the largest available "UV" ( nightlight ) fluorescent type bulb & fixture with a long enough cord to reach your house.

Get a piece of corrugated tin ( roofing material ) and place it at a steep angle with one end in the tub , mount the fixture you just bought on the high end.

Make sure it's sturdy, you don't want the wind to blow it in the water.

Before you go to bed turn it on, in the morning your wife can sell the bugs to recoup the setup cost.

Your trees will be happy and the organic forum will be happy.

Regards

[drtreelove]

When in Rome, do like the Romans do.

The most harmless and productive option is :

Somewhere near your trees, set up a large tub filled with about two inches of water.

Go to your local hardware store and buy the largest available "UV" ( nightlight ) fluorescent type bulb & fixture with a long enough cord to reach your house.

Get a piece of corrugated tin ( roofing material ) and place it at a steep angle with one end in the tub , mount the fixture you just bought on the high end.

Make sure it's sturdy, you don't want the wind to blow it in the water.

Before you go to bed turn it on, in the morning your wife can sell the bugs to recoup the setup cost.

Your trees will be happy and the organic forum will be happy.

Regards

Now I like that option. Keep the WMDs on the shelf and just eat the little suckers ourselves. Is that biological control? I guess plant pest predators come in all sizes, shapes and forms.

[wontok]

Thanks Soidog2 for the suggestion - we're off to get a UV light this morning.

I just wish they tasted better! Maybe with some garlic and a little olive oil....

Thanks again to all of you

wontok

[drtreelove]

This just in from the author of Plant Diseases and Insect Pests - "The green scarab in the photo is Anomala grandis. While the brown I think belonging to Adoretus sp. It is a leaf-eating scarab. I saw some of similar species, but not yet identified feeding on mango leaf at my house at night in Bangkok."

Regards,

Pisuth E.