Saturday Gardening Thread: Bugs [Y-not and WeirdDave]

Greetings Gardeners! Welcome to your Saturday gardening thread.

Today's thread is brought to you by the RHINOCEROS BEETLE:

I have no idea why I decided to post that video... lol!

Earlier this week a friend and I went to the Red Butte Gardens at the University of Utah's campus. It was a gorgeous day and while we were there I spotted this guy buzzing around some Syrian oregano flowers:

I'd never seen anything quite like this wasp before, so I snapped a bunch of pictures and when I got home discovered that he was most likely a Great Golden Digger Wasp, which is a beneficial insect. (So is the rhinoceros beetle and its relatives, by the way.) 'Seemed like a good topic for the gardening thread so here we go!

GREAT GOLDEN DIGGER WASP
This is a type of predatory wasp that preys on grasshoppers and katydids. They are not particularly aggressive. (I can attest to this as I had to really hover over the wasp I was trying to photograph, something I would not have risked with a hornet or yellow jacket.) As far as I can tell, they only eat insects, but the one I spotted was hanging around flowers behaving as if it was foraging. I'm not sure how to interpret that.

Cognitive scientists are interested in studying these insects because of their genetically-programmed behavior:

Upon capturing a suitable prey, the female Great Golden will paralyze it with toxins in her sting. If the prey is small, she flies it directly to the nest. If prey is too large to transport aerially, the wasp will walk with it across the ground. The prey is clasped beneath her body by grasping its antennas with her mandibles.

Once the Great Golden reaches the opening of her nest, she sets the paralyzed insect down. Leaving the prey outside, she goes into the tunnel for inspection. When satisfied that all is well, she comes partially out from the nest and again grasps the prey's antennas pulling it backwards into the nest's interior where it is deposited in a cell with its head turned to the bottom.

Though the prey is permanently paralyzed, it is able to eliminate feces and slightly move its antennas and mouthparts. Great Golden females close the nest each time prey is placed inside. When she re-enters for egg laying, she emits a set of buzzing sounds as she compacts the earth closing the entrance.

There are several behavioral aspects to this "self-programmed" wasp that continue to fascinate as humans tend to think such rote habits denote forethought and logic. Douglas Hofstadter and Daniel Dennett, two professors of Cognitive Science, created a controlled environment to study the Sphex routines more closely.

After the Great Golden dropped her prey and was inspecting her nest's interior, the professors moved the prey a few inches away from the opening. When the wasp emerged ready to drag the prey in, she found it missing. Quickly locating the prey, the professors believe her "behavioral program had been reset" as they found that, once again, she dragged the prey back to the threshold of the nest, dropped it and repeated the nest inspection procedure.

During one study, this was done 40 times, always with the same result. This test can be replicated again and again, with the Sphex never seeming to notice what is going on, never able to escape from its genetically programmed sequence of behaviors.** The wasp never "thinks" of pulling the prey straight in, but continually drops it outside until she is done with her nest inspection.

**Hmmm, reminds me of the RNC.

LADY BUG (officially called a "Lady Beetle")
I think most people realize that lady bugs are "good" insects to have in your garden. Your local garden center may even sell them. If not, you can buy them online. (I did this a couple of years ago to rescue a flowering plum tree that was inundated with aphids and they did a great job.)

Lady Beetles belong to the family Coccinelladae and their good reputation is well-earned. Most of the 450 native and introduced North American species are voracious predators of destructive plant-eating insects such as aphids and scales. In fact, their habitat is determined by what they eat.

Lady Beetles can be found on any crop that is susceptible to aphids: vegetables, grains, legumes, strawberries and tree crops. Females even lay their eggs as close as possible to aphid colonies. Lady Beetles will also consume mites, moth and beetle eggs, thrips, pollen and nectar.

Various species of Coccinellidae share many characteristics. Most are dome-shaped and quite small (1mm to 10mm or 0.63/16 to 6.30/16 inch). While color and patterns vary from species to species, most tend to be variations of red, orange, or yellow with black. Some are simply black.

The life cycles are quite similar, too. Most Lady Beetles begin life as one of a small cluster of tiny (1mm or 0.63/16 inch) spindle-shaped cream, yellow, or orange eggs laid in protected sites on stems and leaves. In about a week, the eggs hosta into alligator-like larvae with 3 pairs of prominent legs.

The larvae are often gray or black with yellow or orange bands or spots. After 20-30 days, the larvae pupate, then emerge as adults in another 3-12 days, depending on temperatures and species. Adults may live only a few months to more than one year.

Just how effective are Lady Beetles with pest control? The Convergent Lady Beetle eats its own weight in aphids as a larvae and consumes up to 50 a day as an adult. Its cousin, the Seven-spotted Lady Beetle adult dines on several hundred aphids daily, while the larval form eat may 200-300 as it develops.

If you want to attract lady bugs to your garden, there are some plants that you can keep that the little gals like, including marigold, sweet alyssum, and yarrow. Although lady bugs are best-known as aphid-eaters, it turns out that the adults must eat some pollen in order to be able to reproduce.

PRAYING MANTIS
These are my favorite insects by far. Seriously, I would keep them as pets if it were considered acceptable behavior! I'm pretty sure when I was little I saw some nature show about praying mantises and was completely hooked on these creatures. Here are some things you may or may not know about them:

Mature adults usually live from spring to fall at which time they mate. Within a few weeks after copulation, a female praying mantis usually die. The male literally loses his head during the mating process for the female simply bites it off and eats it. While this behavior is routinely observed in the laboratory, researchers think it is much rarer in the wild. Maybe these cannibalistic actions help explain why mantids are territorial loners.

Mother Nature has gifted the mature praying mantis with a number of adaptations that make it a fearsome hunter. Very unusual in the insect world, the mantid's elongated thorax functions like a neck, enabling the triangular head to turn almost 360 degrees. This feature combined with its two huge compound eyes and three single eyes, give the praying mantis a real advantage in spotting its next dinner. Each foreleg is modified to fold back like a pocket knife, with serrated, spiny edges that end with sharp hooks: all the better to catch and hold a squirmy lunch desperate to get away.

Another advantage for the praying mantis is its coloring. Not only does the mantid's green to grayish-brown offer excellent camouflage in the plant foliage where it prefers to hunt, this color can be somewhat altered by an individual to better match its specific surroundings. The praying mantis will sit and wait or very slowly stalk its prey, sometimes swaying back and forth to mimic plants moving in a breeze, only to become lightning fast when it snares its unfortunate target.

It immediately uses its strong mouthparts to start chewing the still-living prey. Sometimes, the mantid will bite its victim on the neck first, thus paralyzing the insect and avoiding its escape. It is the only predator that feeds at night on moths and is fast enough to catch flies and mosquitoes that venture within its grasp.

All of these characteristics combine to make mantids formidable and almost perfect predators. Why the "almost" qualification? One problem is that the entire family is indiscriminate in what they eat.

While they consume pests such as flies, crickets, moths and mosquitoes, they also devour other beneficial insects, including each other. Larger species (especially those in tropical areas) will chow down on lizards, small mammals and even hummingbirds.

Yikes!

Of course, there are many other beneficial insects. The folks at Texas A & M have compiled an extensive set of web pages describing the ones found here in the U.S.

In addition, there are commercial sources for beneficial insects and many botanic gardens hold classes on how to integrate them into your gardening plan.

What are your favorite garden "bugs?"

And now, here's your scintillating co-host, Weirddave...

This is the guy who needs to be doing the garden thread:

Seems to me that this is definitely "for the love of gardening". This seems like an awful lot of work for something that sells for a dollar a pound at Giant.

Part 2:

Maybe carrots aren't your thing. Perhaps you'd prefer onions. I managed to fail at growing onions this year, it doesn't help that the video starts by saying its almost impossible to not grow onions. It's probably because I failed to water my tiller (3:36).

Potatoes?

Ahh, screw it, I'm not having luck with any of this stuff. Next year I'm going to plant rabbits.

Y-not: Thanks for those videos, WeirdDave!

To close things up, how about a survey? I'd like to know what you'd like to see happen with the gardening thread during the winter months:

As always, send suggestions, complaints, pictures, questions, and kegs of beer to me on Twitter at MoxieMom or to my gee ma il account, bailesworth.

What's happening in YOUR garden right now?

posted by Open Blogger at 05:02 PM

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