Pests and Diseases

Who’s Been Chewing My Plants?

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The holes in the end of this strelitzia leaf just fascinate the Spoiler.

It may be that he has to look past it (as well as several other plants) to see out the window. But he has remarked on them several times and wondered about them.

I am fairly sure about them. I just presume that when the leaf was still furled, some critter came along, took a bite, decided that the leaf wasn’t to its liking and moved on. But the teeth marks remained and became more pronounced as the leaf grew.

Still, the Spoiler rarely wonders, so it’s an interesting thing.

I am more focused on the plants behind the big Bird of Paradise. Some of them are beginning to show signs of different insect infestations. Ah, the signs of spring!

Ants Are Like Weeds–And Us!

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About a week or so ago, we had a little bit of rain and some ants came in. It’s been a very dry spring–as our springs have been, sadly.

But instead of being grateful that we had 3/10ths of an inch or rain instead of the predicted 1/10, I was dealing with The Spoiler, who was demanding that I put down traps for the ants! (For the record, as you may already remember, we don’t use traps–we use those nice ant repellent packets).

So this is why I say that ants are like weeds. When they’re outside, they’re fine and nobody much notices them unless they are ruining your picnic, or biting you, or perhaps, if they are carpenter ants, you might notice if they are menacing a tree.

But inside, they are like weeds, which are sometimes defined as a plant in the wrong place–they are an insect in the wrong place. Spiders are much the same–they are a “good” bug out of place and we want them gone!!

But how are they like us? Well, if you know even a little bit about ant biology and social structure you know that ants live in community and have defined roles. Without going so far as to anthropomorphize these small insects, they do have “jobs,” and they do them well. There are the “scout” ants that find their way into your homes to search out food, the “nurse” ants that tend to the eggs and young that hatch from the Queen, and in some types of ants that we thankfully don’t have here in Connecticut, there are even soldier ants that fight other colonies.

What most astounded me about our recent little infestation–which lasted only so long as it took me to move my repellent packets, mostly–was the behavior. I am guessing that it was scout ants that came inside.

Unfortunately, The Spoiler was kicking up such a fuss that we wound up stepping on some of them–more so that I could keep him quiet rather than out of any dislike for the ants. I knew that they would go back to where they came from–I just didn’t want to listen to the whining and ranting after a long day at work.

I did not pick up the little carcasses, however. I figured that could wait for another day. So imagine my shock when I got up the next morning and they were all gone! Not only had the ants vacated the premises but they took their dead with them! This is why I say that ants are so like us–they take their dead away.

Now, again, I am not presuming that they took them for a proper burial. They may have been taking them to feed them to their young. But they dead were gone from my house. It was just astonishing.

So next time you have ants in your home, I ask two things of you. First, please give your repellent or trap(s) time to work. It is NOT instantaneous.

Next, do remember that these little insects do have a social structure–and try to be as gentle with your pest control methods as you can.

Peonies and Ants

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Ant on a peony bud

So what’s the deal with peonies and ants? They are almost always found together–but why?

On the theory that nature doesn’t make mistakes, or there are no accidents in nature, let’s examine this a little more closely.

Clearly the ants derive something from the peonies, right? If you look closely, you’ll see little drips of what look like water near where the ants are–if it’s still even there. The ants are after the peonies’ nectar. (It doesn’t particularly show in this photo too well)

So now we have sorted our what’s in it for the ants. Is there anything in it for the peonies? Perhaps. As in other relationships, the ants may protect the peonies from other insects that may want to damage their buds.

Here is an interesting article from the University of Missouri that indicates that the ants may indeed be protecting the peonies from other insects and certainly that the use of insecticides are unnecessary.

I have found a simple way to avoid bringing ants in when I cut peonies. I cut them in the morning, shake them gently and then leave then outside in a shaded place until evening. That generally gives the ants time to leave the flowers of their own accord.

And, of course, cutting the flowers once they are slightly more open–I usually do so even just slightly past the “marshmallow” stage recommended in the UM article–also helps because most of the nectar has then gone from the flowers. Once the nectar has gone, so have the ants, generally.

By using these simply management practices, both you and the ants can enjoy the flowers–the ants outside the house and you and the flowers (minus the ants) inside the house!

More Insects of Summer

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Hydrangea leaves with leaftier caterpillar inside

Here’s an insect that’s very easy to find and very easy to deal with.

Inside this crumpled up set of leaves is yep, you guessed it, another green worm. Hard to imagine that the world is so full of green worms, isn’t it?

This guy is called the hydrangea leaftier–kind of a crazy name, leaftier. Maybe it sounded like leaf-tyer to whomever came up with it. For you scientific types, it is Olethreutes ferriferana. Anyway, as you can clearly see by the photo, that’s what this little worm does–it sews itself into a little cocoon of hydrangea leaves–almost always near the top of hydrangea arborescens, or smooth hydrangea plants.

What’s lovely about this insect is that to deal with it, you just cut off the little clump of sewn together leaves and dispose of them in the trash. Don’t compost them or you will give the little worms time to hatch out into the moths which they become and start the whole vicious cycle all over again–because once you have these things, you have them forever unless you manage to rid yourself of them early.

And in addition to marring the appearance of your plants, why do you want to go around cutting off your leaves–or better yet, peeling open the leaves and smashing the little caterpillars, for those of you who like that sort of thing–every year? I know I have enough to do in the garden in the spring without that, thanks!

The Other Insects of Summer

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Lately the media has been all about the Brood X cicada hatching. I am fortunate that they do not make it far enough north to trouble me (one of the very few benefits of living in the frozen north–we do not get any sort of periodical cicadas, just the ordinary dog day kind).

But of course, that doesn’t mean we don’t have insects. And Memorial Day weekend is just about the time when we start having insect damage. This year has been a bit unusual because the weather has alternated between unusually cool weather and unusually warm weather. So the cool weather insects are trying to hang on a bit and the warm weather insects are here too. It’s like an insect bonanza on the plants–although I am sure they don’t think so!

Aphids on a rose bud

For example, aphids, which are normally a cool season insect on roses, are still here. They rarely hang around this long.

Rose sawfly larva damage

And this damage indicates an insect that is just about invisible to the naked eye–the rose sawfly larva. It’s a caterpillar-like creature that is nearly the same color as the rose leaf and it sucks the juices from the leaf–that’s what the little scrapes on the leaf are.

Luckily, up here in the frozen north, we only have one generation of them a year so I do no type of organic control on them at all. They can really disfigure the leaves a bit, but it’s only for a couple of weeks, and then the shrubs put on some nice new growth and all is well.

And this cute little semi-circle is made by the leaf cutter bee. They take out the leaf parts to line their nests in hollow wood. They are native pollinators so it’s important not to use chemical pesticides on your roses–and that includes those “wonderful” systemics that they sell that do everything from kill insects to keep fungus away.

What do you think is harming the pollinators? Please stay away from stuff like that! If public rose gardens can manage themselves organically, so can you!

I find that the same insects recur at the same time yearly. Once you know what to look for, it’s almost as easy as predicting when those periodical cicadas will be back.

What Insect Apocalypse?

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Katydid on fuchsia

I had an interesting experience while I was out walking the dog one quiet Sunday morning not too long ago. Sunrise is getting later so we were out just after sunrise and it was still and quiet–until we approached our property.

As we got in front of the little patch of woods that we have, I heard all sorts of noise. I stopped because I couldn’t identify it at first. I hadn’t heard it anywhere else on the street. Then I realized it was insects. There were cicadas in the trees, and something else chirping, maybe katydids, and I think I am hearing trees frogs.

It’s been so long since I have heard tree frogs that I am not even sure. I used to hear them all the time 20 years ago. Then a new subdivision went in and a lot of trees were taken down and I haven’t heard them since. So how tree frogs might have found their way to our little patch of woods mystifies me, except that it is now one of the few “little patches” of woods left standing.

But whatever I was hearing was so loud that it literally stopped me in my tracks and it was only in front of my property. Everyone else’s property was quiet.

There are all sorts of articles dating back a couple of years ago talking about stories of insect die-offs as dramatic as 75%. This became known as the “insect apocalypse,” and dire warnings and predictions followed.

Fortunately, some of those studies and methodologies proved to be wrong. But for those of us of a certain age, we can notice that, for example, there are fewer of certain types of insects.

I vividly remember the 2 hour car trips to the beach and back as a child. When we arrived around 9 pm in the evening, our windshield and headlights would be bug-spattered.

Car trips of similar duration now don’t leave our cars bug-spattered. And while I am grateful for small favors, I don’t think the insects have become better navigators. I just think there are far fewer of them.

Is this a problem? I will leave that to the scientists to determine. But in the meantime, I will be grateful that I have a cleaner car and a property that welcomes wildlife of all kind, even invertebrates.

Petunia Worm

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I haven’t planted petunias for several years–not since 2014, I don’t think. There’s a reason for that. Every time I do, my container starts looking really good–and then all of a sudden all the blooms are gone from the petunias.

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If I am lucky, I might start to see this. That at least tells me that the worms have arrived.

But I am not one to treat a container of annuals with insecticide, even if the recommended treatment is BT. That kills caterpillars but of course butterfly larva are caterpillars too. So I would just as soon uproot the petunias once they start looking ratty.

What does this critter look like?

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He’s right there in the middle right of the photo, a green caterpillar about a quarter inch long. They can be difficult to see because of course they are the same color as the petunia stem.

They also eat annual geraniums and calibrachoa so this planter will need a refresh shortly.

But summer is very short-lived around here so I can refresh my planter with late season plants shortly.

A Plague of Locusts?

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It’s been a very dry summer–I believe I mentioned Friday that we are in moderate drought. July brought less than an inch of rain and was the second hottest July on record, (last year was the first).

So with the lack of rain, I have been trying to water very carefully–only containers and newly planted plants are getting water from me at this point. But I have rarely seen the gardens look so sad.

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Take this garden for example. This is self-sown goldenrod and asters, with a few other plants added by me in a garden where a magnolia used to grow. The fact that the natives are wilting so severely in a garden that’s actually in a very wet part of my yard (usually) tells you how dry it’s been.

And I suppose I am lucky that I haven’t planted too much due to the pandemic–it would only need watering.

The things that I have planted–or that were already planted years ago–are being ravaged by “critters,” and who blames them? Between the drought and the fact that plants aren’t producing normally because of drought, things are definitely looking for food–and moisture–where they can find it.

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I am lucky to scavenge tomatoes off my own two plants before something–chipmunks, probably–beat me to it. Because the tomatoes are container-planted, I can control the pest damage, somewhat.

But the other day, I came home to find a green tomato on the walk. When I turned it over, dozens of ants scurried away. Ants on a green tomato? Now you know they’re desperate for moisture!

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My sage in the garden has been eaten into lacy bits. I don’t mind–I have more in a container by the door. But what on earth is so desperate that it needs to eat sage leaves? The jagged holes mean it could be anything–beetles, slugs, caterpillars (although I didn’t see any currently)–whatever.

I find that during times of drought things like katydids and earwigs, which normally just eat garden detritus, (the earwigs, I mean) resort to eating “good” parts of plants as well.

And when I was watering the other night, a grasshopper jumped out at me from between 2 containers. Just what I need: a plague of locusts in a pandemic!

Unwelcome Pest

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I acquired two little tropical hibiscus plants early this season–on the same trip that I bought the “invisible” impatiens that I talked about on Monday. One is sort of a red-orange color and the other a orange-yellow color–you know, the tropical bright colors that hibiscus come in!

They haven’t bloomed as much as I would like despite the heat and humidity that we have been having but when they do bloom they make me unreasonably happy. I think it’s just that I can count on one hand the number of trips I have made to the garden center this year so anything blooming in my yard is really making me happy.

I also situated them right next to my door–in among my herbs–so I see them several times a day when I come in and out of the house with the dog. So there’s a splash of color with the herbs when they bloom.

I especially like the yellow one. Yellow is one of my favorite colors in the garden. So I watch the buds as the unfurl.

But last Saturday I noticed something amiss with the buds. They would get to a particular stage–almost open–and then stop. I leaned in closer and reached for one and it came off in my hand.

That’s just not typical–hibiscus aren’t THAT fragile–so I sat right down, picked up the pot and took a closer look. I saw two things that troubled me.

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This was the first. If it weren’t for the presence of the ant on the bud, I might have thought it was mealy bugs. But I didn’t see any full grown mealies–just this sort of white cottony stuff.

So I looked a little more and sure enough, there was a little green wedge shaped bug–a green plant hopper. So the white mess is the wax hiding its nymphs.

My first choice–always–when dealing with any pest–is a sharp blast from the hose, which seems to have worked well and gotten rid of the nymphs. We are in moderate drought so I am trying to be judicious about water use, but at the same time, hibiscus are very sensitive to any sort of insecticide, even organics, so the hose seemed the best choice here.

And so far, so good. No more plant hoppers or nymphs. We shall see if the remaining buds open properly. Fingers crossed.

A Buggy Time of Year

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I mentioned on Monday that we had had the house power washed recently. That turned out to be a blessing in disguise.

Of course I had to move many of the over 100 house plants that I had brought outside so that they too wouldn’t be “power washed” or damaged in the process.

As I was doing so, I discovered that somehow the mealybug infestation that I had indoors had returned and had spread to several other plants.

Now, one of the reasons why I “summer” the plants outdoors is because a lot of these pesky plant issues have natural predators that are kept in check.

Scale, for instance, is nicely handled by wasps and ants.

And the hose washes off spider mites.

But apparently nothing likes mealy bugs. Doesn’t that figure?

Anyway, I found the problem, isolated the infected plants again, and we’ll see. I have one troublesome ficus that may just become compost at the end of the season.

So I definitely got much more than a power wash from this adventure!