Showing posts with label predatory insects. Show all posts
Showing posts with label predatory insects. Show all posts

Wednesday, August 6, 2014

Garden Bugs

As I have been walking around the property I have seen a wide variety of insects. both good and bad.  Of course bad is based on the human perspective of what's eating the plants that I am interested in either for food or aesthetics.   The insect herbivores provide a link between the solar energy stored up in plant materials and animals higher up in the food chain.  The really bad insects are those that don't fit in with the food chain.  Those are the ones lacking a predator.  

Here are a few of the interesting bugs that I encountered in July. 

This moth is about 1.5 inches long.
Clymene Moth is said to be a common woodland species, though I have seen it only this once.  It is a daytime flier so it should not be difficult to spot.  The black cross on the tan wings certainly stood out. 
The larvae feed on a variety of plants, particularly Willows, Oaks and Eupatorium species.  

My wife spotted this Luna Moth while pulling out stiltgrass.  I think it had recently emerged from a cocoon because the wings appeared to be very flexible.  The large adult moths do not feed.  Their typical adult lifetime is about a week.   The larvae feed on several species of trees, including hickories, persimmon and sumacs.   

This moth was in a mass of stiltgrass
We found this lethargic moth in early afternoon,
these moths usually fly at night.

Three of the 6 yellowish spots can be seen
on the wing casings of this tiger beetle.
The 6-spotted Tiger Beetle is one of the fastest running insects.  I've seen them running on our pool deck at 2-3 mph.  Their top speed is 5.6 mph or the equivalent of 480 mph, if it were the same size as a human!   This insect predator is able to easily chase down its prey.  It can fly as well.

The larval form is also predatory.  It stays in a burrow and lunges out to capture passing small insects, like ants and spiders.



The largest of the leafhoppers at over 1/2 inch long is the Broad-headedSharpshooter, Oncometopia arbona.  This insect feeds on plant juices and shoots the liquid waste in an intense stream, hence the name 'sharp-shooter'.   It has the overall shape of other leafhoppers, but it is much bigger.   Leafhoppers are vectors for a number of plant diseases.  This one can carry a bacteria that causes Pierce's disease in grapes.  
The jewel-like coloring of this insect caught my eye.  It was tough to photograph
because it kept scurrying to the opposite side of the cucumber from the camera.

I only found this Mantis because it was moving,
otherwise it would have blended into the grasses.
At 4 inches, this is probably a Chinese Mantid.
The largest insect predator that I've spotted so far is the Praying Mantis.  The really big ones are actually imported Chinese Mantids.  The native Carolina Mantid is brownish-grey and about 2 inches long.  They feed on a wide variety of insects, whatever they can grab with their powerful front legs. Mantis are noted for their ability to rotate their heads 180 degrees.

We saw one on the outside of our kitchen window that had spotted a Japanese beetle on the inside.  It moved carefully into position and tried to grab the beetle through the glass.  After a couple of attempts I squished the beetle and took it out of sight.  The mantis then just walked away into a nearby hanging basket.  



This Cucumber Beetle is a bad actor in the garden.
I saw this green spotted beetle in the vegetable  garden the other day and while I did not know what is was, but I was pretty sure it was not something I wanted.  My method of choice this season for dealing with garden pests is squishing.  So that's what I did.  It took quite a bit of force to kill this beetle.  (Cabbage moth caterpillars are much easier to dispatch.)  I got a photo so that I could do an ID after the fact.  Turns out I made the right call.  This was a Spotted Cucumber Beetle.  These beetles feed on the leaves of cucumber and melon plants and can spread bacterial wilt that will kill the entire vine.                  


These moths hover near flowers and gather nectar through their long proboscis.
Hummingbird Moth at a Wild Bergamot, Monarda fistulosa.
The Hummingbird moth is fairly common around here.  It flies during the day and makes a humming sound when it flies, similar to a hummingbird.  It also looks and feeds similar to a hummingbird.  This mimicry offer some protection from predators.  There are two common species in the US.  The one I saw recently is the Snowberry Clearwing, Hemaris diffinis.  It dominant in the western US, but its range is from coast to coast.   The other species is the Hummingbird Clearwing, H. thysbe.  It has a red body and is found primarily in the eastern half of the US. 

The larvae feed on honeysuckles, hawthorns and Prunus species.  The pupae are found on the soil surface, or over-wintering in the leaf litter.
       

My favorite garden predator is the Wheel Bug, Arilus cristatus. It is rather frightening in appearance in all its growth stages.  Like the mantis the wheel bug feeds on a wide variety of insects, but I am especially happy when it gets a Japanese beetle or a stink bug.  They move slowly to get close to their prey then grab hold and pierce them with their long pointed beak.  They inject enzymes to dissolve the insides of their captive.  While beneficial in the garden, they can inflict a painful 'bite' to humans if they are threatened with no clear escape.
Evening Primrose, Oenothera biennis, is a favorite of Japanese Beetles.
It is also a good place to find Wheel Bugs.  You can see
the dark beak sticking into the beetle.


Thursday, June 27, 2013

Co-existing with Nature

There is a conflict between nature and designed human space.  We like to have our nature neatened up and easily readable with beautiful plants arranged just so.  Nature is just do what it needs to survive, with each of its members seeking out their basic needs: food, shelter and reproduction.  Conflict arises when our focal plantings become a meal or natures breeding habitat becomes a lawn.

In putting in our new garden and new plantings I have been trying to work with nature to achieve my design goals and keep our vegetables ‘safe’ without destroying too much habitat or employing chemical weaponry. 

The double fence has been keeping the deer at bay.  The outer border has been planted with seedlings of
pollinator-friendly perennials.  I may not get too many flowers this year as these plants get established.

To help control garden insects I have left some meadow areas intact that provide habitat for predatory insects.  I have also planted a border around the garden with pollinator friendly plants.  In selecting these plants I chose ones that are listed as deer-resistant.  To combat the beetle population I have a jug of soapy water.  This works well on some of the bugs whose escape strategy is to drop to the ground.  I just hold the jug under them and they drop in when nudged.

Here are some photos of predatory insects that are in the yard.  In addition to these I have seen the 6-spotted Tiger Beetle, very cool!
This nymph of a Wheel Bug looks like something from
the movie, Starship Troopers.
This 2-inch mantid was hopping from stem to stem in a patch of
moss phlox as I was looking for a Tiger Beetle.

Compared to the green sweat flies, Long-legged flies are aptly named.  
This 1/2 inch fly is a general insect predator.



Most of the landscape plantings I have selected are not deer favorites.  For those plants that are on the deer’s menu I have been using repellents that are either scent-based (putrescent eggs) or taste-based (capsaicin/hot pepper).  The hot pepper spray seems to be effective at getting the deer or rabbits to stop feeding on a plant even after they have gotten a first taste. 

You can tell deer damage by the ragged edges they leave where they tear off leaves and stems (deer don't have upper incisors).  Rabbits have sharp teeth and will leave a clean cut, or they will consume a plant right to the ground.  

The following are lists of plants that have I have put in that are 1, deer candy; 2, occasionally browsed; 3, not bothered by deer.  It is still early in the season and these comments are based on how they treat the foliage.  Flowers will be another subject (see some comments).  While it is risky to proclaim a plant to be deer proof, I have not seen any damage to the plants on this list (yet).

The buds on this Magnolia were being eaten off
until I put on the chicken wire cage 
1.  Heavily Browsed
Apios americana 
Helianthus tuberosus 
Magnolia virginiana 
Rudbekia triloba 
Campanulastrum americanum* 
Zizia aurea

*These were very small and eaten to the ground so rabbits or some other critters were responsible for this damage. 

The pinnate leaves of the ground nut have been
chewed off in more exposed locations


This Jerusalem Artichoke was being browsed to the ground until the fences went up.
Now (June 27) these are 6-7 feet tall.



This Filipendula was nearly ready to bloom when the deer
ate off most of the upper growth.  Note the rough edge
where the deer ripped off the tip of the plant.

2.  Occasionally Browsed
Achillea millefolium (flowers were removed, the foliage was left behind)
Aronia melanocarpa 
Hibiscus moscheutos (just once)
Filipendula rubra (just once leaves and flower buds, not after hot pepper spray) 
Lobelia siphilitica 
Physostegia virginiana 
This Hibiscus had the tips chewed off, but no more
damage since I applied some hot pepper spray.
Rudbeckia hirta 

(The Lobelia had been untouched until yesterday.)













3.  Resistant, so far
Aquilegia canadensis 
Asclepias tuberosa 
Asclepias incarnata 
Ceoanthus americanus 
Chamaecrista fasciculata  
Chelone glabra 
Dicentra eximia 
Hedeoma pulegiodes 
Iris versicolor 
Monarda didyma 
Monarda fistulosa 
Monarda punctata 
Spiraea alba 



As far as keeping the critters out of the garden, the double fence method is still working.  I’ve been able to harvest snap peas, lettuce, chard and collards, so far.

I did notice some evidence of moles digging around the property.  For these I put down a perimeter treatment of MoleMax, a castor oil based product that moles and other burrowing species do not like.