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GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published May 22, 2016

Not long ago a local gentleman called me because he had rescued several mantid egg cases laid in some tires that were being hauled away. He had heard that mantids were beneficial and wanted to protect the egg cases until they hatched. I am not an entomologist, so my knowledge of mantids is not vast but, I have learned a little about them because they are frequently encountered in gardens.

The mantid that most often catches our attention in local gardens and landscapes is the European mantid (Mantis religiosa). It is native to Europe, Asia, and Africa and reportedly entered North America on some nursery plants around 1899. It definitely prospered and can now be found throughout the US and Canada.

Some gardeners even buy mantid egg cases because the mantids are touted as beneficial insects. This is debatable. They do feed on other insects, but they do not discriminate between bad insects and good ones, like including butterflies and bees. However, they can certainly be appreciated as an insect curiosity.

The European mantids are not usually noticed in the garden early in the season when they are very small, but by the end of summer their elongated body has grown to a length of three or four inches and they are easily seen.

One thing that makes the mantid so fascinating is its unusual appearance. It looks a little like an insect that works out because it has large, well built spiny forelegs. The “praying” moniker comes from its forelegs that appear bent in prayer before they are used to quickly reach out and snatch prey.

Along with its “muscular” forelegs and elongated body, is an alien-like triangular head with large bulging compound eyes and a big, strong mouth for biting off the heads of prey. The mantid is also able to rotate its head 180 degrees, allowing it to scan a wide area for potential victims.

Another interesting trait of mantids is their ability to change color to blend in with their background. Their body may be colored bright green, brown, reddish brown, or gray depending on their surroundings. This ability allows them to camouflage themselves and let their unsuspecting prey come to them.

Did you know that mantids are sexually cannibalistic? The females are known to bite off the heads of a male during the act of mating. You can find videos of this phenomena online, but scientists say that this behavior occurs less than 30% of time when mantids mate in the wild. They speculate that it occurs when the female is hungry and needs nutrition for egg laying. Speaking of cannibalistic behavior, nymph or “baby mantids” eat each other if they do not have access to other food immediately upon hatching.

After mating, female mantids lay up to several hundred eggs in cream colored foamy egg masses that look somewhat like a styrofoam packing “peanuts” when they dry. The egg cases are typically attached to rocks, fence boards, tree trunks and branches, and the walls of structures. The adults do not survive the cold temperatures of winter, but in the spring their offspring hatch from the egg cases.

By the way, there is native mantid in eastern Washington. It is Litaneutria minor or the agile ground mantid. This ground-dweller is only about an inch and a half long and dark gray to tan in color, making them much less noticeable than the alien European mantid.


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published- JULY 11, 2014


I recently overheard a woman in a local store asking for a spray to kill the little green worms on her lettuce. I had to restrain myself from offering her unsolicited advice. I too had just found ‘little green worms’ on my lettuce, but I recognized them as syrphid fly larvae.

Syrphid flies are also known as hover flies or flower flies because they are usually noticed when hovering over flowers. They may cause alarm because they have a black and yellow striped body, resembling a bee or wasp. However, syrphid flies are benign and do not sting or bite.

The adult flies eat flower pollen and nectar. They are also valuable pollinators. You should not be afraid when you see a syrphid fly hovering around your garden plants, but any aphids present should be very afraid. That is because many types of syrphid flies are predaceous. These syrphid flies lay their eggs near colonies of aphids. The eggs hatch into hungry larvae that will eat hundreds of aphids in a month.

If you see a ‘little green worm’ on a plant infested with aphids, take a close look. Syrphid fly larvae have a tapered body with no legs. They blindly move over the leaf surface searching for aphids to eat. When they find one they use their piercing mouth to suck out its body fluids.

So if you find a little green worm on your lettuce or see a bee-like fly hovering around your flowers, it is likely a sphyrid fly larva or adult. Syrphid flies are beneficial insects that do double duty, eating aphids and helping with pollination. Encourage them instead of buying a spray to kill them.

For much more information about ‘Beneficial Insects, Spiders, and other Mini-Creatures in Your Garden – Who They Are and How to Get Them to Stay’ go to for your free downloadable copy of this outstanding and fascinating publication written by Dr. David G. James, Associate Professor, WSU Department of Entomology.

Several local gardeners have come to me recently because they were worried about the silvery patches on the leaves of their zucchini plants. They wondered if it was powdery mildew, a fungus disease that is fairly common in area gardens. It first shows up as small white powdery spots on squash leaves. These spots grow larger until the fungus covers the entire leaf and stem, killing the infected tissues It typically shows up on squash late in the growing season, about the time the plants are finished producing fruit.

Luckily, what these gardeners have encountered is the natural silvery blotchy variegation characteristic of some zucchini cultivars (varieties). It is not a problem and the plants are healthy for now, but it is advisable to watch for signs of powdery mildew on squash, cukes, and melons.

If you have had problems with powdery mildew on your squash before, you may be able to avoid it by doing a few simple things. When possible, plant cultivars that indicate they are resistant to powdery mildew. Don’t plant your squash or other cucurbits where they will be in the shade of other plants or structures for part of the day. Provide good air circulation by not crowding the plants. Finally, rotate your crops so cucurbits are not planted in the same location for at least two years. For more information on powdery mildew go to WSU’s Hortsense Website at:

Published: 7/11/2014 11:39 AM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published- AUGUST 15, 2014


There has been much attention given to the devastating losses of honeybees in our country due to pesticide poisoning, mites, and more. Did you know that these valuable pollinators are not native to North America? The Western honeybee (Apis mellifera) was imported by European settlers who came to this country to farm in the 1600s. It was just one of the domesticated animals they brought along with them.

Honeybees create new colonies, increasing their numbers, with swarming behavior. Wild honeybees move out as a swarm from one colony to start a new colony. This swarming behavior was responsible for the honeybee migrating northward and westward from Virginia where they are first believed to have become established. By 1843 they had reached Kansas, then moved further westward when Mormons took them to Utah in 1848. Transporting hives by sea, a botanist introduced Western honeybees to California in 1853.

We have come to rely on the industrious honeybee for pollination of many of our commercial crops and are very concerned about the decline of both wild and domesticated Western honeybee populations. However we should not forget native pollinators, such as the over a dozen species of bumblebees in the Pacific Northwest. These large furry bees are also hard workers, helping to pollinate many of our fruit and vegetable crops.

Bumblebees nest primarily in underground cavities, such as abandoned mouse burrows. New nests are started by overwintering queens. Each queen starts a new colony by laying no more than six eggs in her new nest. These eggs hatch into sterile female workers who care for the queen, the additional brood she begets, and the nest.

Unlike much larger honeybee colonies, a bumblebee colony will have a maximum of a few hundred workers. At the end of the season the queen will lay both female and male eggs. These will hatch, emerge from the nest, and mate. The mated females become next year’s queens and find a protected place to spend the winter. All the other bumblebees in the colony, including the old queen, will die.

You must be familiar with the loud buzzing of bumblebees in the garden. You may think that this sound comes from the movement of their wings, but it is actually the rapid vibration of their flight muscles. They use these same vibrations to warm up their bodies to fly in cool weather, allowing them to fly earlier in the season and at lower temperatures than many other insects, including honeybees, can fly.

Like honeybees, bumblebees help with pollination by moving pollen from flower to flower as they work to collect nectar and pollen for feeding their colonies. However, they are also ‘buzz’ pollinators. The vibration of their flight muscles also vibrates the flower they are visiting. Some flowers are ‘self-pollinating’ and do not need a transfer of pollen from another flower. However, movement from wind or ‘buzz’ pollination is needed to shake the pollen off the anthers within the flower. Crops helped by buzz pollination include blueberries, cranberries, kiwi, eggplant, peppers, and tomatoes.

Bumblebees, honeybees, and many other native pollinators are at risk. As gardeners, there are some very simple things we can do to help, like planting a pollinator garden that includes native flowering plants. Avoid using insecticides in the garden. Learn more about our native pollinators so you can protect their habitat and make sure these extremely valuable natural resources are not lost.

Published: 8/15/2014 11:36 AM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
Published 7/25/2013

I created a challenge for area gardeners a couple of weeks ago when I mentioned that the newer synthetic pyrethrins, also known as pyrethroids, are one of the few options for controlling tobacco budworm and sunflower moth in garden flowers. Just what are these ‘newer synthetic pyrethrins?’ Before answering that question, let’s first talk a little about the origin of pyrethroids.

One of the first botanical or plant derived insecticides was pyrethrum. It was made by drying and crushing the flowers of two types of daisies, Chrysanthemum cinerariifolium and Chrysanthemum coccineum. When purified this mix was called pyrethrin. Pyrethrum and pyrethrin were desirable because they were ‘natural,’ had a relatively low toxicity, and had a very short residual. While a lack of persistence is valuable in protecting beneficial insects, it also made them less effective in controlling insect pests.

Another obstacle to their use was that pyrethrum was expensive and supplies were limited. This prompted the pesticide industry to look for a way to create a synthetic pyrethrin. This was accomplished in 1949 when the first synthetic pyrethrin, allethrin, was developed. The next generation of pyrethroids came in 1960 with the introduction of tetramethrin, resmethrin, bioallethrin and phenothrin. This second generation was more toxic than natural pyrethrum.

Chemists did not stop there. They have continued to develop new pyrethroids that are more toxic and most having longer residual activity. These are the ‘newer’ pyrethroids I referred to a couple of weeks ago. They include esfenvalerate, permethrin, cyfluthrin, and bifenthrin.

Home gardeners with insect pest problems have been frustrated in recent years because a number of insecticides that they used successfully in their gardens for pest control were taken off the market because of health and environmental concerns. These newer pyrethroids are effective against a wide range of garden insect pests, especially chewing insects, and have helped replace materials, like diazinon, that are no longer available.

As a group, the newer pyrethroids are generally low in toxicity to mammals and birds, but highly toxic to fish and beneficial insects. They are fast-acting and kill insects both by contact and ingestion.

How do you know if a product contains one of these newer pyrethroids? I found out it was not easy when I went looking for one on the shelves of local stores. Product names don’t give you a hint. You have to check the label for active ingredients. There will usually be a common name, such as esfenvalerate, along with its long chemical name in parentheses. Check the label to make sure it includes the crop, such as flowers, on which you plan to use the material. Also note any precautions you should take to protect yourself and wildlife.

By the way I was able to find several Bayer, Ortho, and other brands home garden products that contained at least one of these newer pyrethroids.

Note: It’s hot out at this time of year. If you spray your plants with any type of pesticide, check the label to make sure you are in the recommended temperature range. Applied in hot weather, some materials can damage your plants.

Published: 7/25/2013 11:03 AM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
Published 11/23/2012

As a little girl I can remember watching a green chrysalis turn into a beautiful monarch butterfly. It was amazing!

The distinctive orange and black monarch butterfly (Danaus plexippus) migrates each year from northern areas east and west of the Rockies to spend the winter in Mexico and along the California coast. There are two different groups or populations of monarchs, the eastern population breeds in the east and overwinters in Mexico and a few of the warmest southern U.S. states. The western population breeds in the west and overwinters in sunny California.

East or west, it’s only one generation of butterflies that fly south in late summer, some traveling as much as 3000 miles, but it takes three or four generations of the butterfly to make the return trip all the way back to the northern U.S. and Canada each year.

To enable this long trip back, the multiple generations of monarchs depend on milkweed they find along the way. Adult butterflies feed on the nectar of milkweed and other flowers, but monarch larvae only feed on milkweed. Without milkweed, they can’t reproduce.

Because of threats to its milkweed habitat and overwintering sites, there is concern over the monarch butterfly. While not yet an endangered species, monarch enthusiasts are worried because the monarchs aggregate in large populations in a limited number of sites when overwintering in Mexico and California. This makes them particularly vulnerable to logging, development, agriculture and other human activities.

There is also concern about the loss of milkweed habitat in this country, as well as the possible toxic effects on monarch populations from the pollen of genetically modified corn.

While USDA researchers at the Agricultural Research Service’s Research Unit in College Station, Texas were researching a better chemical lure to trap boll weevils, a serious pest of cotton, they discovered a lure that’s attractive to milkweed stem weevils. Stem weevils are a major milkweed pest. This serendipitous discovery will be used to develop a trap that will help scientists monitor the movements of the stem weevils and protect the prized monarch’s milkweed habitat.

Home gardeners can help too. The Monarch Joint Venture (MJV) is a partnership of federal and state agencies, non governmental organizations, and academic programs that are working together using a science-based approach to protect the monarch butterfly. They note that changing land management practices has led to a loss of native milkweed. The MJV is urging home gardeners to plant milkweed in their gardens.

Monarch Watch, a volunteer group of monarch and milkweed advocates, recommends planting milkweeds native to the region in which you live. They have identified the common species of milkweed that are found in different regions of the U.S., that are used by monarchs during their migrations, and that are easy to establish. A list of these milkweed species can be found on the Monarch Watch website ( info sheet.pdf).

Planting regional milkweed species is ‘easier said than done’ because you can’t find packets of milkweed seed at any garden store. To help you locate sources of regional milkweed seeds and plants, Monarch Watch has also put together a list of vendors for each region. ( back the monarchs/resources/plant seed suppliers)

You can be part of the effort to protect the awesome monarch butterfly, both by planting some milkweed in your garden and by learning more about the attempts to protect it. Every child should have the chance to see this awesome creature turn from striped caterpillar, to chrysalis, to beautiful butterfly.

Published: 11/23/2012 1:16 PM


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Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

Boy, was I surprised to find a praying mantid in my hand instead of a the leaf I thought I was picking up! This fall I’ve run across several mantids in the garden. ‘Mantid’ is a broad term that refers to all members of the Mantid family and ‘mantis’ is more specific referring only to members of the Mantis genus.

Here are the top five reasons that I find mantids fascinating insects:

1. They’re aliens: While there is a small (one inch long) gray native mantid found in our region of the state, it’s rarely encountered. The most common alien mantid in our area is the European mantid (Mantis religiosa). It came to the US hitchhiking on a shipment of nursery plants sent to North America in 1899. The European mantid is two to three inches long and bright green to tan in color . It has a black ‘bull’s‑eye’ on the inside surface of its front legs.

Another common species in Washington is the Chinese mantid (Tenodera aridifolia sinensis), introduced into the US in 1895 from China for the purpose of pest control. It’s from three to five inches in length and green to brown in color. The egg cases of both are now commonly found for sale in nurseries and via mail-order.

2. They’re cannibals: The primary diet of these large mantids consists of insects that come to them, including beetles, leafhoppers, flies, grasshoppers, moths, spiders, and honey bees. They’ll also eat other mantids and their own siblings, especially right after they hatch. While there is a general belief that female mantids eat their mates, some reports suggest that this is because investigators used starved mantids in their studies. I guess that means a male mantid should determine if his female mate has a full stomach before getting romantic!

3. They look weird: These insects have fascinated observers for centuries because of their strange appearance. They’ve been given the descriptive name of ‘praying’ because of the way their front legs fold, resembling a person with their hands folded in prayer. While they may look like they’re folded in prayer, these raptorial forelegs are what make mantids such effective killers. There are spines on the upper insides of their legs that allow them to grasp and hold onto helpless prey. Did you know that mantids usually bite the head off their victims first before consuming the rest of the body?

The mantids’ head and bulging eyes are features that makes them fearsome garden predators. Mantids can turn their head more than 180 degrees while looking for prey, plus they have two big compound eyes and three simple ones that enable them to see prey 60 feet away.

4. They blend in well: Mantids are experts at camouflage. The European and Chinese mantids are able to their change body colors (in shades of green to brown) to match the background where they’re sitting.

5. They’re not effective garden predators: Although mantid egg cases are often sold for controlling garden pests without pesticides, mantids aren’t effective predators. With only one generation a year, their population in the garden builds up quite slowly. Instead of hunting, mantids wait for insects to come to them so they aren’t good at controlling the most common damaging pests in the garden, like caterpillars, mites, and aphids. Also, don’t forget they’re cannibals and will eliminate other mantids in the area competing with them for food.

They may not be effective in controlling garden pests, but mantids are certainly fun to watch. Aren’t they awesome?

Published: 10/12/2012 11:32 AM


written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

This is the time of year gardeners start to prepare their gardens for winter. It’s also the time of year that Halloween decorations start to appear. Ghouls, monsters, pumpkins, spiders, and bats seem to be a pervasive theme. Halloween is all about spooky and scary things, but we do an injustice to spiders and bats who are actually two of our garden friends. Making them out to be frightening creatures is unjust.

Generally, spiders should be regarded as good guys. Why? According to Dr. Linda S. Rayor, Assistant Professor of Entomology, Cornell University, ‘Spiders are considered to be the most important terrestrial predators, eating tons of pest insects or other small arthropods every year. Spiders are generalist predators that are willing to eat almost any insect they can catch. They are abundant and found in most habitats. They only need to be left alone!’

That’s why I get upset when I hear about folks who want to spray around their homes to kill all the spiders and other insects because one or two might find their way inside. This certainly knocks the balance of nature out of kilter. When spiders migrate inside at this time of year looking for a mate or a warm spot to spend the winter, just smash them with a shoe or tissue. If you have lots of spiders migrating indoors, it probably means that you need to tighten up your home, replacing weather stripping on doors and sealing cracks and crevices that provide entry to spiders and other creatures.

A common ‘scary’ spider noticed at this time of year are the orb weavers (Araneidae). There are a variety of different orb weavers, some with interesting angled peaks or tubercles on their large abdomens. They can also be quite colorful, coming in a variety of colors including orange, yellow, black, white, and brown.

A female orb weaver can appear quite large at this time of year because she is carrying several hundred eggs in her abdomen. Before the end of fall she will create an egg sac and then die before winter arrives.

The orb weavers build amazing large wheel-like circular webs that are works of art. When insects find their way into an orb weaver’s web, their vibrations enable the spider (orbs have poor vision) to locate and trap their hapless victims. Most orb weavers rebuild their webs every day.

So if you see spiders or their webs around your yard and garden don’t be alarmed. Don’t try to kill them. They’re helping keep insect populations in check. If you see spiders inside the house, just usher them back outside where they can do some good or smash them.

Bats also eat a tremendous amount of insects, including mosquitos, and should be considered our friends. As with spiders, by encouraging bats we’re allowing nature to keep the insects in our yards and gardens in check.
Published: 9/29/2011 12:10 PM


written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

I noticed a large green mantis hiding amongst the leaves of my potted herbs. He was patiently waiting for a large grasshopper to come to him. The grasshopper came closer and closer and then suddenly the mantis pounced, trapping the grasshopper with its forelegs and taking a big bite out of the still struggling captive. I just couldn’t keep watching this gory display, even if the grasshopper had been nibbling on my herbs.

The two species of large green or brown mantises that are sometimes found in local yards and gardens are aliens. These non-natives, the Chinese mantis and the European mantis, were introduced into this country about 75 years ago to provide natural control of crop insect pests. These vicious predators didn’t turn out to be good pest managers, but the mantises have prospered and spread throughout the U.S. and Canada. While not very effective in controlling pest populations, gardeners still buy mantis egg clusters for release in their gardens.

Why aren’t they effective? As vicious “meat” eaters, the mantises eat insects, but they attack both bad guys, like aphid and moth pests, and good guys, like bees and spiders. Another reason for their lack of effectiveness is that mantis populations are slow growing, making it difficult for them to keep up with quickly burgeoning pest populations.

One reason mantis populations grow so slowly is that there is only one generation a year. The other reason is that mantises are territorial and cannibalistic. Oh my! This nasty predilection prevents a buildup of the mantis population. If gardeners try to help out by placing numerous egg cases here and there, the mantis numbers still don’t seem to grow significantly larger. That’s because the hatching mantises either eat each other or quickly move to where there is enough food and places to hide.

Hiding is what mantises do well despite the rather large three inch elongated body of the European mantis or the even larger Chinese mantis. Their lanky green to brown bodies easily blend in with plant leaves and stems.

In the fall, female mantises lay 30 to 300 eggs, enveloping them within a frothy gummy substance and gluing them to plant stems or other objects. The gummy substance turns hard, protecting the eggs over the winter. The adults die a little later, leaving only the eggs to survive the winter. In the spring, the eggs hatch and tiny baby mantises emerge from the tan colored shingled egg cases. The babies or nymphs eat and grow, molting numerous times until they reach maturity.

While the mantises that gardeners like me encounter are usually the introduced aliens, there is a native species found in the wild sagebrush areas of eastern Washington. The native “ground mantis” is gray and about one inch long.

How did mantises get the common name of praying mantis? That’s simple. When they lie in wait for their prey, they hold their front legs together at an angle that makes them look like they’re praying. I think they look like they’re rubbing their “hands” together in anticipation of dinner. Maybe they should be called preying mantises instead.

Published: 8/29/2009 11:25 AM


written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

It was serendipity a week ago when I was at a WSU training conference and found myself in a class about bees… I had meant to go into a class on weeds. The topic of this seminar wasn’t honey bees or my favorite, the bumble bee. It focused on some of the other bees that can act as pollinators.

The class instructor started by pointing out that there are two main types of bees, social or more correctly “eusocial” bees and solitary bees. Eusocial bees form colonies with many workers that forage for food and rear the young. Honey bees and bumble bees are the best examples of the eusocial type. A good example of a solitary bee is the leaf cutter bee where the adult female bee builds her nest and provides for her own offspring.

In a way, leaf cutter bees are familiar to many home gardeners. The female of this little bee uses her scissor-like jaws to cut out pieces of leaf tissue for her nest. She is able to cut an almost perfect circular hole one-quarter to one-half inch in diameter from the edge of a leaf. She uses each circular piece of leaf to line her nest and create a cell where she will lay an egg. She fills the cell with collected pollen and nectar to nourish the “baby bee” or larva as it grows. Depending on the size of location she has selected for her nest, she will cut out more circles to create additional cells. The leaf cutter bee spends the winter as a pupa, then spins a cocoon, and emerges as an adult bee the next spring.

Leaf cutter bees seek out small holes or cavities in which to situate their nests. In the garden they like to nest in the hollow centers of rose canes created by borers or in the hollow stems of other plants. Rose leaves seem to be one of their favored garden plants for cutting out leaf circles for their nests.

There are a number of native leaf cutter bees, but the alfalfa leaf cutter bee, Megachile rotundata, is not native. It originates in Eurasia and has been used in the western U. S. for pollinating alfalfa grown for seed production. The leaf cutter bees are much more effective in pollinating alfalfa than honeybees or other types of bees. Perhaps its because they don’t mind the top lid of the alfalfa flower banging them on the head when they go in and out of the flower.

There are even bee “brokers” who raise leaf cutter bees for use in alfalfa seed production. These brokers create nesting boxes by filling a box frame with plastic drinking straws or by drilling lots of holes in styrofoam trays. The bees find these nesting boxes handy and will use them for laying their eggs instead of looking for plants. The bee brokers store these nests over the winter in a warehouse where they can control the climate. In the spring, they take them out in the field when alfalfa is in flower.

Leaf cutter bees are hard workers, even harder workers than honeybees. It only takes 150 leafcutter bees to do the work of 3000 honeybees! The adult bees are usually smaller than a honeybee and gray in color. They’re most active when the temperature is above 70 degrees Fahrenheit, working from early spring to late summer. While they will pollinate different flowering plants, they have a preference for the flowers of legumes.

A cousin of the leafcutter bee, is the blue orchard mason bee, Osmia lignaria. Much like leafcutter bees, the female mason bee finds holes already present in wood and uses them for her nest. The holes must be about one-quarter to three-eighths inch in diameter, just a little larger than the mason bee, which is a little smaller than a honey bee.

They get their name because they’re a shiny dark blue and from the way the female builds her nest, using mud to plaster the bottom of the hole. She then collects food, pollen and nectar and provisions the cell for the egg she than lays there. Next, she seals the cell with more mud and creates another cell, repeating the process until the hole is almost filled with cells. She finishes off the nest by sealing it with a mud plug.

Unlike the leaf cutter bee, the blue orchard mason bee lives a fairly short time, only about a month. During that time a female can produce about two eggs a day. The eggs hatch into larvae and are nourished by the food left in the provisioned cells. Each larva spins a cocoon and pupates in the cell, changing into an adult before winter. However, the adult stays in the cocoon and waits until spring to emerge when the weather is warm enough. The adult bee then chews its way out of the cell, mates, and the process starts all over again.

Mason bees have become a popular pollinator in home orchards. Gardeners construct mason bee “houses” to encourage their nesting. Many of these bee houses are constructed out of pine or fir cut lengthwise. Holes are drilled three to six inches deep in the wood to create nesting places for the mason bees. Some gardeners also use nests made of boxes filled with drinking straws, just like for the leaf cutter bees. The houses or nesting boxes are attached firmly to a structure in a location where the bees have been observed and hopefully they move in. This docile little blue bee is really quite amazing. It’s such a good pollinator, that it only takes about 250 mason bees to do the work of 60,000 honeybees. It gives new meaning to “busy as a bee”!

The alkali bee, Nomia melanderi, is a native solitary bee that’s been used to pollinate alfalfa and some other agricultural crops in our region. It gets its name because it nests in alkaline soil, preferring bare soil areas that stay moist, but not wet, most of the time. The females create cells in the soil about four to eight inches below the surface. While they are solitary bees, they tend to nest together in an area. Some alfalfa producers feel the alkali bees are the best alfalfa pollinators and have encouraged alkali bee populations by creating artificial nesting sites, but these are much more difficult to create than the nesting boxes or bee houses used for leaf cutter and mason bees.

Thankfully, one solitary bee that can’t be found in this region is the carpenter bee. These big bees “drill” their own holes or tunnels in wood for their nests. Their tunnels can be several feet deep. They prefer soft woods that have been painted or that are still covered with bark. While they do pollinate some crops in the areas they reside, they aren’t highly prized pollinators.

I’m glad that I accidentally attended this class. It gave me the chance to learn more about some little bees that I didn’t know much about before. Now you know about them too.

Published: 9/24/2005 11:39 AM


written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

If you pick up a flower pot set on the ground, it’s not unusual to find all sorts of nocturnal creatures hiding beneath it during the day. When you lift the pot, these little fauna scurry to find another dark place for protection. Some of these scampering fellows are likely to be predacious ground beetles. You may also occasionally find a lost ground beetle indoors, hiding under a laundry basket or pile of clothes in the laundry room. When encountered, the first reflex we have is to stomp on them.

Few of us feel like letting them go on their merry way, but you are encouraged to learn to recognize them as friends, not foes that need to be squashed. According to WSU Extension Entomologist, Dr. Arthur Antonelli, the different types of ground beetles found in Washington feed on a variety of “insects and insect-like creatures, many of which are garden or house pests, such as cutworms or house fly maggots. One specific group of ground beetles feeds on snails and slugs.” While they may also feed on some desirable critters, they are considered a beneficial insect because of the good they do.

Predacious ground beetles belong to a very large insect family of beneficial beetles called carabids (Carabidae family). Just in North America there are several thousand named species and over 40,000 in the world. They get the name of “ground” beetle because the majority of these beetles in temperate zones are terrestial, living close to the soil under pots, rocks, or garden debris, yet there are a number of tropical species that live above ground in trees.

To protect this valuable insect resource in your garden, you need to be able to identify them. Keep in mind there are numerous species and they don’t all look exactly alike. The ground beetles found in Washington range in size from one-eighth of an inch long to one and one-quarter inches long. They’re generally elongated with a body that tapers to a smaller head with long legs and long antennae. Most ground beetles we will encounter in our yards and gardens will be black or dark brown in color, but there are some that have more of a purple to metallic green appearance. These characteristics may be hard to verify because the beetles are quite fast, especially when scurrying for cover.

The ground beetle starts out life as an egg that hatches into a larva. It’s interesting that the larvae feed using “external digestion” where they spit their digestive juices onto their food, turning it into liquid nutrients. They then suck up the juicy digested matter. The larvae are worm-like, somewhat flattened, dark brown to cream in color, and a bit tapered at each end. Like the adult, the larva also has noticeable large mandibles (jaws). The larva then turns into a pupa before emerging as an adult. This all takes about a year for most of the ground beetles in Washington. Depending on the species, the adults may live for one to three years…unless some callous gardener flattens them with their shoe.

Dr. Antonelli notes that the four most common species of ground beetles in Washington are the European ground beetle , the green pubescent ground beetle, the common black ground beetle, and the boat-backed ground beetle. One of the ones most common in our region of Washington seems to be the common black ground beetle with lengthwise grooves on the wing covers over its back.

Dr. Antonelli cautions us that ground beetles are “often the victims of broad-spectrum insecticides used around the home and garden, especially when insecticides are used beyond an intended target plant or site.” When we apply pesticides to large areas, such as the foundation of the house, to reduce the population of a particular pest, we may be shooting ourselves in the foot by killing predators. Predatory insects, such as ground beetles, are responsible for helping us keep pest numbers down. It’s important to protect these valuable garden predators, not kill them. Predacious ground beetles are our friends.

Interesting Ground Beetle Trivia

Researchers and farmers at OSU

s Integrated Plant Protection Center have been developing “beetle banks” where they create raised beds four to six feet wide situated in the agricultural fields. These beds are planted with native bunch grasses and provide an area where ground beetles can thrive and eat harmful insects in crops planted nearby.

When threatened, many native species of ground beetles secrete stinky chemicals to deter animals from eating them. One such beetle is the”bombardier beetle” that emits toxic chemicals from its anal glands. These chemicals explode into puffs out the rear end of the beetle with an audible sound. It’s said to discourage frogs or other predators from eating them. I bet it does!

You can raise your own ground beetle to observe. Go to for information on how.

Published: 7/21/2008 2:46 PM



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