Thursday, January 23, 2014

Untold Stories of 2013: When Insects Attack!

While we wait for spring to come, I thought I would share some of my untold gardening stories from 2013. The blog posts I started and never finished.

One of the things I remember most about 2013 was the invasion of insect pests in the garden. Perhaps "plague" would be a more accurate word. Insect pests were everywhere. Some caused quite a bit of damage, while others were more of a nuisance. Some of of these invaders I had never seen before. 


The insect to cause the most widespread damage was probably the colorful Four Lined Plant Bug. I never got a good picture of this critter because they drop from the leaf they are feeding on when you approach. I did happen to get a picture of one having its juices sucked out by an Assassin Bug. Still not a great photo.

Having your juices sucked out by an Assassin Bug is a fitting fate for a Four Lined Plant Bug because that is what they did to the leaves of my Gregg's Mistflower, Gregg Salvia, and Liatris. You can see some of the damage in the upper left of the photo above. Since Gregg's Mistflower and Gregg Salvia grow so fast, they quickly outgrew the damage to their leaves.

The damage to the Liatris, however, was so intense and prolonged that the leaves turned almost white with scabs and I think it cause several of the plants to die when they began blooming. I must say that I am not 100% certain that the damage to the Liatris was caused by the Four Lined Plant Bug, but I am pretty certain.

I tried controlling the Four Lined Garden Bug with a light horticultural oil, but since the insects drop to the ground when they feel threatened, they are hard to hit with a spray of the oil. 

Light horticultural oil is the strongest insecticide I use and I only use it on rare occasions. It is paraffin based must come in contact with the insects to kill them by suffocation. If you can't coat the insect with spray, it will not die. Light horticultural oil also works pretty well on leaf fungus too.

Grasshoppers are always present in Texas. In fact, I disturbed a 3.5 inch long one in the garden this past weekend. The season started out looking like it would be a bad grasshopper year, but I never noticed any more damage than is visible on these rain lily flowers.

The Coreopsis Leaf Beetle is another pest that caused damage last year, specifically to Coreopsis plants. My photos of this insect must have been really bad and I deleted all of them. You can see a great photo and find more information at the link. This beetle pretty much destroyed all of my Correopsis plants last year. I used light horticultural oil a couple of times to control this pest.

I have four varieties of milkweed plants to provide food for monarch caterpillars. I knew when I planted them that I would also have aphids. The two seem to go hand in hand or plant in mouth. 

The aphid infestation on the milkweed was actually pretty light last year. They hit once in the spring and never again. They are fairly easy to keep under control by spraying them off the plants with a strong stream of water from a hose. There are almost always a few lady bug beetles and their larva feeding on the aphids too.


Another pest common to milkweed is the Milkweed Bug. They appeared in the garden about three years ago and feed on the milkweed seedpods. The do not seem to do much damage to the plants otherwise, but they are very prolific. I keep them under control by squishing them between my thumb and forefinger, usually gloved, but not always.

A newcomer to attack the milkweed in my garden is the Swamp Milkweed Beetle. To the uninformed, this pest might look like a large lady bug. Instead of eating aphids, like a lady bug, the Swamp Milkweed Beetle will quickly defoliate milkweed plants. I have only seen the beetle on tropical milkweed in my garden. It does not seem to bother the native varieties of milkweed. This is another pest that is easy to control by the squishing method.


Who knew that an insect attacks the Texas Bluebonnet? I did not, until last year when I found the seedpods covered with Conchuela Bugs. This was another new pest to me. They began appearing after the seedpods began forming. I assume they were feeding on the developing seeds. 

My method of control for the Conchuela Bugs was to move the Bluebonnet plants to the compost pile before all of the seeds were mature. 

Leaf footed Bugs are regular visitors to my Red Yucca plants each year. They hang out and feed on the flower stalks and seedpods. The only thing I do to control these pests is to remove the seedpods. This seems to make them go away for a while until more seed pods form. The plants look better without the seedpods too. Once the flower stalks are about bloomed out, I cut them off and the Leaf footed Bugs will go away, but not far. 

They also like Datura leaves and seedpods. 

Flea Beetles appear during the summer and eat holes in the leaves of some Clammyweed plants. It is interesting that the insects will make some of the plants look like their leaves are made of lace, while a plant inches away will go untouched. The Clammyweed is usually about bloomed out by the time the Flea Beetles hit so it is not much of a loss. Besides that, I am removing the plants by this time of year to keep them from reseeding too freely.
And who could forget the attack of the Big Yellow Caterpillar

6 comments:

  1. What a "fun" post! And I feel your pain as I have a lot of these same visitors every year. The four-lined plant bug usually does damage to my salvia farinacea early in the spring and then they go away and the plants outgrow it. I can't believe you have already seen a grasshopper in January!!!! Seriously? What is the world coming to?! The flea beetles have descimated my calylophus in years past. I cannot believe how quickly they devoured that plant!! And this year were wreaking havoc on Lamb's Ear. Kind of hard to spray anything on Lamb's Ear because it makes the foliage look worse than just the insect damage, so I usually just try to keep them cleaned up and eventually the beetles left. And I always get aphids on the milkweed, too....right about the time the Monarchs are supposed to come through, and I'm torn between wanting to cut off all the blooms and get rid of as many aphids as I can and wanting to leave what's left of the blooms for the butterflies. It would be a full-time job spraying them with water, but I have done that on a few. Do you have any crape myrtles? Have any crape myrtle scale? I had one tree with it this year, but at the church garden I maintain some of the trees there have been infested. Thankfully the twice-stabbed lady beetle came to the rescue. If you "build" it, they will come. I was so excited to see them on the property. I love seeing nature take care of nature :-)

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    1. Toni, I think that grasshopper was overwintering in some leaves and came out to enjoy some sun. I have seen a few others on warm days. The good thing about most insect pests is that they come in cycles. Some years may be worse than others and when they do hit, they usually do their damage and then they are gone. I had crape myrtles when I moved into this house, but they had been butchered (crape murder style) in the past. After a couple of years, I decided to take them out. That was right before everybody started having trouble with bark scale. I agree, it is great to see nature taking care of nature.

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  2. Your post is sad but it has helped me identify many of those creatures who munched on my plants last year. I will be better prepared this year. It took me a long time to find the big yellow caterpillar. . . .very funny!!

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    1. I am glad you were able to identify some of your critters, Ann. I hope this year does not bring any more new pests. I was glad that big yellow Caterpillar did not do any damage in my front yard. This year, they are active in the neighborhood alleys so I may have another report on their damage.

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  3. I am not sure I am right, but in my garden, where I garden without spraying, I noticed that some years I have a huge population of a certain bug, one year it was black aphids, one year they were gray, another year I had huge amounts of flower bugs. I pretty much left them alone since the damage was just cosmetic (but managed to squeeze many of the big ones by hands). Then I noticed that the next year they were really at a minimum. I believe that by leaving the pest on my plants I fed a nice population of other insects that predated on the pest. Then in the spring the beneficial was already present in the garden and took care of the pests in no time.

    I hope that this is the case in your garden and this year you will have much fewer bugs.

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    1. I think you are right, Laura. The insect pests come in cycles as do their predators. I am trying to develop a balanced ecosystem in my garden and let nature run its course. I only step in with a direct spot treatment of light horticultural oil if the infestation is severe and concentrated. Last year was the first time I had done this in years. I doubt that I will need to do the same this year.

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