Saturday, August 11, 2012

Zebra Bug - Longhorn Beetle - ANSWERED

We recently visited friends in Vancouver Island, British Columbia who have a mini-farm with chickens and sheep, an orchard with apples, peaches, sugarplums, blueberries, kiwis, and figs, plus a show-stopping garden full of tomatoes, peas, beans, squash, lettuces, artichoke, and everything else.  Oh, and dinner plate dahlias.  I get lost in their garden every time I visit.   

During my tour through the blueberry patch (in between popping blueberries into my mouth), I came across a fascinating bug. 


I believe it was dead when I took these pictures.  I nudged it with my finger and it didn't react.  That's why I was able to run to the house and get my camera, and still find it in the same place.  That also explains why its back left leg is bending the wrong way.  But I think it's really pretty.   Do you know what it is? 


Hey Way,

I have to admit, I saw this and my heart started beating really fast. This is a longhorn beetle, so-named because their antennae are often longer than their bodies. They are a boring insect, and generally attack trees. This one looks a lot like an Asian Longhorn beetle, which would be really, really bad.  Luckily, it's not. It's a North American variety, called a Banded Alder Borer, and they generally attack trees that are already on the ground. Therefore they aren't really pests. They like to lay eggs on the creases of alder trees (and some others). The eggs hatch and then bore under the bark and into the wood. The adults feed on flowers, which is likely why it was in the garden. Knowing that it's a Banded Alder Borer means that it's okay to marvel at how beautiful it is!  You can find this species on the western coast all the way from Alaska down to Central and Southern California and New Mexico.

This is not an Asian Longhorn Beetle, but it is important to be able to identify the differences.
Asian Longhorn Beetles are a serious pest. They were discovered in Brooklyn in 1996. Shortly afterward, they were all around New York. Several trees in Central Park had to be removed due to infestations. Since then, they've spread to New Jersey, Chicago, Ohio and Massachusetts. They found 6 infested trees in Boston, directly across the street from the oldest arboretum in the United States. Massachusetts has removed at least 28,000 trees so far. Ohio is at serious risk, due to how much of the economy depends on the trees. They have invaded Britain, Germany and Austria. They have been discovered in warehouses throughout the country, including the British Columbia and Washington State. Luckily, fantastic warehouse workers have caught them before they were allowed to get out.  This pest chews up a lot of deciduous trees. Think the dreaded bark beetle in the west, except that they aren't picky about trees: ash, maple, birch, elm, poplar, willow, and several others.

People who live in New England should report any sightings of this insect. This site provides a lot of good information. The "Spot It" tab has a bunch of pictures and information on how to identify both the beetle and the damage. You can also report a sighting.

Identifying the Beetle:
The Asian Longhorn Beetle looks a lot like this one, in that they are zebra striped. They are shiny black beetles with white stripes/spots on their bodies and on their antennae too. The antennae are longer than most other beetles' antennae, and can even be longer than their body. The Banded Alder Borer, however, has a white thorax with a big black dot. The Asian Longhorn has a black thorax. The thorax is the segment right below the head. The neck, if you will.

Asian Longhorn Borer:
Not One: Here's the lovely gal you discovered, a Banded Alder Borer:

See the difference?
Here's another picture of an Asian Longhorn Beetle:

On the eastern coasts, you won't see the Banded Alder Borer, but there are some other lookalikes. This site does a good job of helping you identify them.
But if you are in an infested area, and you see something you think could be an Asian Longhorn, I'd just go ahead and report it anyway. It can't hurt and it might save all the trees in your neighborhood.

And people throughout the country should have a general idea what to look for. We really don't want these spreading.

Sunday, August 5, 2012

Sticky Webbing on Zinnias & Fennel


I love zinnias.  Pacific Northwesterners don't seem to grow them much, but to me they are the epitome of summer.  Little globes in crayola colors.  Besides, they remind me of Val's garden, which is pretty much the flower garden of my dreams.  I planted mine in the front yard, so I see them every morning when I leave for work. 

Even though zinnias are annuals, I want to make them last as long as possible.  So I've kept a close watch on them.  I noticed some very fine webbing on the flower petals: 

In one case, there was even a dew-like substance clinging to the webbing:

There is also some leaf damage: 

In the back yard, quite a long way away from my zinnias and on the opposite side of the house, I may have the same problem on my fennel.  Serious dewey webbing:

That thing in the middle of this photo was a dead moth, I think. 

I know that I have aphids on the fennel, but I don't think aphids make webs like this.  So I'm guessing it's something in addition.  I looked for the actual insect but either it's too small to see or it hides during the day when the sun is out.  

What do you think?


Sunday, July 1, 2012

Damage to Clematis Flowers - Answered


My clematis struggled for the last two years.  But finally, this year, it's turning out big purple blooms one on top of another.   In the last couple of weeks, I noticed that something is eating large chunks out of the flower petals. 

While the damage looks similar to slug damage, there are two reasons I think it might not be slugs:  (1) the clematis grow up a tall metal obelisk trellis, and all of the flowers sit on the very top, which is a long way for slugs to climb, and (2) the leaves appear untouched, with only the flowers exhibiting the damage.  Could it be earwigs?  How would I find out?

Take a look:

I searched for caterpillars and slugs on the foliage and undersides of the blooms.  Nothing.  So I don't have anything for you to identify.  Do you have any ideas what it could be?

I did notice a spider with a web across one portion of the plant (and did not photograph it because I know you hate spiders), but it didn't look like it was causing any damage to the foliage.  Anyhow, my  philosophy about spiders in the garden is that they are generally good. 


Answer -


I think you're right. Without seeing the culprit, I would guess earwigs. They feed at night and move down to the soil during the day, which is why you wouldn't see them. And they seem to have a hankering for clematis flowers too.  Slugs would be eating indiscriminately, and they don't generally enjoy climbing metal. Caterpillars would probably be eating the leaves as well. If you look closely at the flowers, do you see any small (very, very small) pellets or dots of dirt? That would be frass, or caterpillar poop. If you see any webbing (that isn't from spider mites) or any pupae, then it would be caterpillars as well. The spider is definitely helping as a generalist predator, so best to leave it. (Thanks for not taking a picture, I'm light years better than I used to be, but "surprise spiders" still make me jump).

Earwigs usually aren't a problem in mature gardens, despite the scary name. They actually eat aphids and eggs of other pests, so they can sometimes benefit a garden. They like cool, moist places during the day, which is why you can find them in basements or bathrooms on occasion. They can't really hurt you with the "pinchers" on their abdomens, and they aren't really prone to crawling into ears. They eat all sorts of things: detritus, aphids, insect eggs, and mites; but they will also sometimes feed on young plants, flowers and fruits. When that happens, there are some fairly easy ways to control them.

Earwig Control:
One thing you can do is to eliminate a lot of the hiding places they use in the daytime. If you have any potted plants, logs, or anything they can hid under during the day, you might move those to a different part of the garden for a while. Clean the area around the ground if you have any leaves or ivy around the base of the plants that you can sacrifice. If you can afford to without hurting the plants, you might remove any mulch under the plants temporarily. You probably won't be able to eliminate every place they would hide, but every little bit helps. The nice thing about earwigs, though, is that they are easy to trap. Insect traps are so satisfying, when they work, because you get to see the results of your labor. People have all sorts of earwig traps they swear by. Some people think they are more attracted to beer than anything else. Others think a little fish is in order. Some people just put a rolled up newspaper or cardboard in the garden and let it get wet during watering, so that earwigs move there during the day.  I personally like oil traps. You put out a couple of cat food cans and either fill them with 1/2 inch of some kind of fish oil or vegetable oil with a dollop of bacon grease. Earwigs are highly attracted to fish oil, but you might also attract cats and other creatures. Of course, the bacon grease might attract other things too. This trap will attract them while they're feeding. In the mornings, you can empty them and refill. At the same time, you might try a trap for resting earwigs, such as the aforementioned newspaper. In the evenings, you shake the earwigs out into a pan of soapy water.

You can buy earwig bait and some sprays for earwigs, but it seems unnecessary when the home solution seems to work better. So I recommend that you try some traps. Unless, of course, you see some frass on the leaves. Then you should apply some Bt for caterpillars. :)


Black Bugs on Tomato Plant, Part III - Using a Keyboard Vaccuum to Kill Flea Beetles


Your birthday gift left me initially puzzled -  a computer vacuum with 9 different attachments - but then I remembered your advice about the flea beetles.  Of course, it is a bug vacuum.  :)  It works surprisingly well on the flea beetles.  Here are some action shots: 

They kept hopping around inside the vacuum.  For everyone else out there, this tiny little garden tool is the Dirt Devil Detailer and it's about the size of a banana.  The suction feels quite light, which is good because it caused no damage at all to the leaves.  In fact, it barely pulled on the leaves when I vacuumed the bugs.   

As I dispensed flea beetles, I happened to come across that exact same mystery bug from last year.   At least, I think it's the same one.  The one with clear wings.  Interestingly, I tried to vacuum it up but couldn't.  Perhaps it grips the leaves??  I took two pictures, one from the side and one from the top:

I saw at least 3 on my tomatoes today.  However, there doesn't actually seem to be any damage associated with them.


Saturday, June 9, 2012

Black Bugs on Tomato Plant Revisited - ANSWERED


Last year I posted a question about mysterious black bugs on my tomato plants, and we never got to the bottom of it.  The bugs are back - this year even worse than before.  I found them on my potato plant too.  The damage looks like many small holes.

Here are pictures of the plants and damage:

Potato Plant (this first one I think they're mating):

You told me to capture one of the bugs, put it in the freezer, and then take close up pictures of its mouth parts.  As I tapped a few of the bugs into a tupperware for freezing, I noticed the bugs move almost like fleas.  They hop super fast.   You see the bug, then it vanishes and reappears a few centimeters or inches away.  Even so, it wasn't difficult to capture a few of them. 

Unfortunately, I didn't get any good pictures from the frozen bugs.  My camera takes pretty good closeups, but the bugs are so small I couldn't get pictures with any resolution of their body parts. Instead, I tried to get a few more pictures showing them on the leaf:

That's the best my camera can do.  What do you think?



Hey Rachel,

So, this is a different kind of "little black bug" than the one from last year. I'm still not sure what those things were, but they definitely weren't beetles. These are clearly Flea Beetles. These little guys are kind of cute, but they can do a lot of damage to seedlings.

You can tell these are beetles because of the hard shell that covers their wings. It's called a carapace. If the insect is at rest, and you can still see clear wings, then it probably isn't a beetle. If you see a hard shell, it's likely a beetle. I was already thinking flea beetle because they are so small, but you also discovered how they got their name: They jump like fleas!  The damage also fits. Flea beetles are one of the relatively rare pests in which the adult causes the most damage. They chew the leaves and create holes we call shotholes, because it looks like buck shot (rabbit shot? tiny thing shot? I don't know much about shotguns).

Look familiar?

They're a common pest in spring and early summer. The adults lay eggs in cracks in the ground around the plant. The grubs feed on plant root hairs, but they rarely do much damage. It's the adults who cause the most problem, chewing through seedling leaves. They don't usually hurt an established plant, which can handle a surprising amount of damage without dying. Well, if they chew holes in a beautiful lettuce plant, it probably still sucks. With a tomato plant's leaves, though, you're probably ok if the plant is established. If it looks like they are really hurting the plant, there are a few options.


These guys don't respond very well to pesticides, and they're also pretty good at evading natural enemies (the jumping thing). It can make it difficult to control them. Some people put out sticky traps (those yellow cards covered in resin), but I've heard they don't work very well. Diatomaceous Earth works really well on beetles. It scratches the wax layer on their exoskeletons and makes them lose water. You can apply it to the leaves. It shouldn't hurt the plant. The only problem is that you have to apply it after every rain or watering that gets on the leaves. Row covers or any kind of mesh cover will work to exclude them in the first place. If you ever have them on your seedlings, then this is a great way to control them. You can try it on established plants too; you just need to remove them sometimes for pollinators. To be honest, though, a lot of people vacuum them.  Do you have a handheld DirtDevil or anything like it? They work really well, because they won't suck up the plant leaves. You can use a regular vacuum attachment, but you'll need to be really careful that you don't damage the plant leaves. Just hold it at an angle pointing to the sky above the plant. When you do this, make sure you don't block out the sunlight. A good shadow will make these guys scatter. Part of the reason they are difficult to control comes from their ability to disperse quickly. So, try to sneak up on them. I've never tried it myself, but I've always wanted to give this particular piece of advice. (Mostly because it makes me giggle to think of stalking tiny beetles with a vacuum cleaner). They actually make bug vacuums, which are mostly for kids or people scared of bugs in the house. These are probably over-priced for what you get. We used a keyboard vacuum (you know, the kind that picks up dust) to remove moths from the wind tunnel in grad school. It worked really well.

Now I'm going to go back to the previous black bug post to look at the damage again. I think some of the damage may look like flea beetle damage. If they hid when you approached, it's possible that your picture was of the wrong culprit.