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THE SCIENCE OF FALL LEAVES

GARDEN TIPS – Written by Marianne Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published October 30, 2016

Fall is my favorite season of the year. Growing up in the northeast part of the country, I have always been enthralled with trees changing color in the fall. The bright red, orange and yellow colors of autumn are marvelous. I can recall collecting the prettiest leaves on my way home from elementary school and bringing them to my mother.

After I became a science nerd, I wondered how this miracle of nature happened each year. It is because fall’s shorter days and cooler weather cues deciduous trees (ones that lose their leaves) that winter is coming. The leaves stop making carbohydrates via photosynthesis. Chlorophyll, the green pigment in leaves essential to photosynthesis, starts to break down. As the chlorophyll dissipates, the yellow and orange pigments already in the leaves become visible. In addition, anthocyanin pigments may develop in the leaves of some trees, resulting in red and purple leaf colors.

A variety of weather conditions influence the development of fall color. Fall colors will be their brightest when fall days are sunny and nights are cool and dry. Cool, dry conditions speeds the breakdown of the chlorophyll. Sunny weather promotes the production of the anthocyanins. If trees are drought stressed going into fall, the development of fall color may be delayed or can also result in early leaf drop.

Natural leaf drop is also part of the fall leaf phenomenon. Leaf drop occurs because the shorter, cooler days also prompt a layer of cells (called the abscission layer) to form where the leaf is attached to the twig. This layer of cells blocks the flow of water and nutrients in and out of the leaf. As the leaf begins to decline or senesce, it starts to produce ethylene, a plant growth regulator. Ethylene stimulates the production of enzymes that break down the cells in the area where the leaf is attached to the tree. This weakens the attachment and the leaf falls from the tree.

Some species of trees, such as oaks and beech, do not shed most of their dead leaves all at once in autumn. Instead, the leaves drop gradually over the winter or when the new buds begin to grow in the spring. This is called marcescence. Occasionally, marcescence occurs on many other types of trees as a result of a very early hard freeze. An early freeze surprises trees before the abscission layer has had time to form.

One thing you might not know is that needled evergreens also shed their “leaves” or needles in the fall, despite the descriptive epithet of “evergreen.” Each year the oldest needles on evergreens, such as pines, turn yellow, orangish-tan, or brown and drop from the tree. In most years, the change in color and drop of needles happens gradually and goes unnoticed except for the piles of needles beneath the trees. Other years, it can happen all at once and cause concern when it is observed.

In our area this phenomena is most often noticed on long-needled pines, such as ponderosa pine and white pine, as well as on arborvitae. If you note it and are concerned, check to see if the yellowing or browning needles are the older growth towards the inside of a branch. If the tips of branches on the outside of the tree or shrub are turning yellow or brown, there may be a problem worthy of concern.
Despite recent rainy weather, my two red maple hybrids, a Marmo maple and an Autumn Blaze maple, are turning delightful shades of red and orange. How about the trees in your yard?

FALL A GOOD TIME TO CONSIDER THE TREND OF TIDY GARDENS

GARDEN TIPS – Written by Marianne Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published October 23, 2016

The Garden Media Group predicts that one of the new garden trends for this coming year is “tidy gardens.” In essence this is the de-cluttering of the garden and coincides with the U.S. shift to urban living, with many moving away from suburbia and back to living in cities. This population shift brings with it smaller houses, yards, and gardens, a trend we have been seeing for a while.

The Garden Media Group (GMG) points out that tidy does not mean sculptured hedges and immaculate garden spaces. Tidy translates to simplified, less cluttered gardens that require less input. GMG notes that an important part of achieving a tidy garden is getting things under control.

Crowded gardens are cluttered gardens. If your perennials have grown too big, divide them and share them with other gardeners. Too often shrubs and trees are planted too closely together when young and become crammed together as they grow and mature. Sometimes judicious pruning done properly may help, but this locks you into repeated pruning in the future. Simplify by removing some of the plants to make more room for the others.

However, it is extremely difficult for gardeners like me to remove a plant. It is a bit like choosing one of your children over another. One must harden one’s heart and decide which plants are not contributing significantly to the overall beauty of the landscape or garden. It could be the ones beset by insect or disease problems, or those that have outgrown their space, or mature plants that are past their prime. Of course, GMG suggests keeping the plants you love the most and the ones that are flourishing in your garden.

When establishing a tidy garden, GMG recommends keeping things simple by using a “restricted palette of plants and hardscaping.” The smaller the “palette” or number of different plants is a hard precept for avid gardeners to follow. Gardeners like me delight in a diverse mélange of garden plants. It helps to think of a landscape and garden like a home. A crowded and cluttered home takes more time and effort to keep neat and clean. The same goes for a crowded, disorderly garden. Gardens are probably more enjoyable when they are not a chaotic jumble of plants.

Gardeners wanting to create a tidy food garden should look to the many new dwarf varieties of edibles available on the market. Plant breeders continue to develop bush vegetables that take up less garden space and can be grown in containers or raised beds. Many can also double as ornamentals. In addition, there are compact berry bushes that can be grown in containers on the patio or planted in the garden where they take up much less room than the large leggy berry bushes of yesterday.

There are also beautiful new compact ornamental plants, including the new flowering shrubs that are smaller and more prolific bloomers than their predecessors and the increasing selection of dwarf conifers that do not require frequent hedging to keep them within their allotted space.

Whether your goal is a trendy tidy garden or just one that does not require as much work, take some time in the coming fall and winter months to take a critical look at your garden and landscape. Decide what plants should be removed and what ones should be replaced, but keep in mind the words of the French poet and theologian, Francois Fenelon, “Exactness and neatness in moderation is a virtue, but carried to extremes narrows the mind.” He has a good point.

WINTER SQUASH AND PUMPKINS ARE SIGNS OF AUTUMN

GARDEN TIPS – Written by Marianne Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published October 16, 2016

You know fall has arrived when tree leaves start turning red and a variety of winter squash, including pumpkins, start showing up everywhere along with pumpkin lattes and a plethora of pumpkin culinary delights. What do you know about these “squashy” signs of autumn?

Do you know the definition of “squash” or, more exactly, the definition of a winter squash? If you check the dictionary, a squash is a member of the gourd family that has edible flesh. A winter squash is squash that is harvested when it is mature with fully developed seeds. When mature, a winter squash has a tough skin or rind that enables it to be stored for a month or more, depending on the type of squash and storage conditions.

From the botanist’s perspective, squash are members the cucurbit (Cucurbitaceae) family. This family is native to South and Central American and may have been cultivated in these regions long before corn became a cultivated crop.

Squash have many cousins in their family including decorative gourds, utility gourds, cucumbers, melons, and summer squash. There are several different species of winter squash. The Cucurbita pepo species includes spaghetti, delicata, and acorn squash. Because most C. pepo squash do not have thick skin, they are not suitable for long term storage.

Winter squash with harder skins that store well for up to several months are the Cucurbita maxima species that includes hubbard, marblehead, buttercup, banana, golden nugget, Turk’s turban, and kabocha squash. Other species that store well are Cucurbita moschata that includes butternut, ponca, and waltham squash and Cucurbita argrosperma that includes cushaw squash.

All pumpkins are winter squash, but the term “pumpkin” is an inexact, nontechnical term that refers to a roundish winter squash with orange-ish smooth ribbed skin. However, not all winter squash that are called pumpkins are round and orange. Pumpkins vary in appearance, characteristics, and use.

Many pumpkin pies you eat come from pumpkin cultivars of C. moshata that have tan colored skin and an elongated fruit shape. This type of pumpkin is used to make canned pumpkin used in making pies and baked goods.

Gardeners trying to grow gargantuan pumpkins for giant pumpkin contests usually plant cultivars of C. maxima. These have creamy white to somewhat orange or yellow skin and a spongy stem. These pumpkins can weigh in at 100 pounds or more. Selections of the cultivar Atlantic Giant produces most of the winners of pumpkin contests.

The Cinderella pumpkin, also known as Rouge Vif D’Etampes, is an heirloom variety that has grown in popularity in recent years. It has flattened fruit with deeply furrowed orange-red skin. It is often used for decorating, but its flesh is supposedly good cooked or in pie. Other heirloom pumpkins on the market are the Jarrahdale pumpkin with blue green deeply ribbed skin and the warty Galeux d’Eysines with salmon colored skin. Both are a departure from the typical orange pumpkin and are reported to have tasty sweet flesh.

When it comes to carving look to the cultivars and hybrids of C. pepo with orange skin and a deeply furrowed woody stems. Also, most of the cultivars with “naked” seeds for eating come from C. pepo, as well as do the miniature pumpkins used for fall decorating. In addition, there are some cultivars of C. Pepo used for making fresh pumpkin pies.

This would be a good weekend to go get your winter squash and pumpkins, if you did not grow them yourself. I want to get one of the carving pumpkins with white skin, how about you?

FOREST BATHING AS A GARDEN TREND?

GARDEN TIPS – Written by Marianne Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published October 9, 2016

I like to keep up with the most current gardening trends so I am always interested when the Garden Media Group (GMG) releases its Garden Trends Report for the coming year. For the next month or so I will share a few of the 2017 trends with you.

One of the 2017 trends GMG notes is “forest bathing.” Wait! It is not what you are thinking. This is not about hauling tubs out into the forest and taking a bath. Forest bathing or shinrin-yoku is the term used to describe this new fitness trend. It simply involves spending more time with nature to nurture all of our senses, reduce stress, and increase well-being. It is a purposeful practice of immersing yourself in nature. According to GMG, forest bathing is a “cornerstone of preventative health care and natural healing in Japanese medicine.”

To be honest I had never heard of forest bathing until I read this report so I did a little research. Forest bathing was started in the 1980s in Japan and is about taking leisurely hikes or walks in natural areas with the purpose of breathing fresh air, relaxing, and connecting with the natural world.

While this might seem like nonsense promoted by nature fanatics or flower children of 1960s and 70s, it is backed up by scientific research. It is not news that spending time in a wooded area or a garden can significantly reduce stress by lowering the cortisol, one of the hormones associated with stress. Chronic stress is associated with the increased risk of heart disease, high blood pressure, weight gain, deterioration of cognitive functions. Research has shown that lowering cortisol and other stress hormones can improve your immune system.

I knew that plenty of research is available documenting the health benefits of interaction with nature in green spaces like gardens, parks, and forests, but I did not know about phytoncides. Phytoncides are natural chemicals released by needled evergreens. Research indicates that when these chemicals are inhaled on a regular basis, they may significantly improve the human immune system.

My research into forest bathing revealed that there is a U.S. organization (www.shinrin-yoku.org) that promotes shinrin-yoku therapy. Who knew? This organization offers three hour therapy walks and seven day immersions in California. The Association of Nature & Forest Therapy Guides & Programs (www.natureandforesttherapy.org) trains and certifies therapists or guides from other parts of the country so the practice of forest bathing can be spread to other parts of the country.

I am not sure we need to practice forest bathing in an actual forest. I bet we can gain similar benefits by spending time in our gardens, tending the plants, hearing the hum of honeybees and other insects, and appreciating nature. Folks without a garden should make a habit of visiting the Master Gardener Demonstration Garden located behind the library at 1620 South Union. This almost three acre garden is a delight any time of year.

In the Master Gardener Demonstration Garden you can discover how restoring it is to sit for a while on the bench in the Bird & Butterfly Garden or relax in the Serenity Garden, listening to the sounds of nature. Of course, if you want to breathe in the phytoncides of an evergreen forest, you will need to drive to the Cascades and take a hike in the woods. Make it a leisurely hike and breathe deep while amongst the trees. Ahhh!

PLANT FALL CONTAINER GARDENS NOW

GARDEN TIPS – Written by Marianne Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published October 2, 2016

Last weekend I decided it was the end of the season for the two large flower container gardens that sit on each side of my front door. The most recent bout of wind had decimated the large coleus plants and the beautiful petunias were finished flowering. Now the containers are empty because I have yet to decide whether to fill them with fall flowers, plant them with spring flowering bulbs, or simply finish the cleanup process and get them ready for next spring.

I like planting frost tolerant fall flowers in my planters to extend the season, but often wonder if their relatively short display of beauty outweighs the time and expense. While combinations of the typically available choices of mums, flowering kale, and pansies can be attractive, they do not lend much versatility to fall container garden design. However, creative gardeners can utilize perennial herbs and flowers, ornamental grasses, shrubs, and even frost tolerant vegetables in the planters for something a bit different. The perennials that survive the winter cold can then be relocated to the garden next spring.

Better Homes and Gardens suggests using colorful coral bells (Heuchera), Heucherella, asters, grasses and sedges, kale, swiss chard, dead nettle (Lamium), and silver sage (Salvia argentea) in fall planters. Look through a vegetable garden catalog and check out the foliage of kale, Swiss chard, beets, and lettuce. Their leaves can provide interesting color and texture in a fall planter, plus you can eat these fall veggie crops. Also, the blue-gray foliage of garden sage (Salvia officinalis) and rosemary contrast nicely with purple-leaved kale and chard.

If you decide to depart from the ordinary and plant perennial flowers, herbs, or even shrubs in your fall planters, it is important to note that even plants hardy for our region (Zone 6) may succumb to winter cold. This is because the roots of plants in containers are subjected to colder temperatures than if planted in the garden. When planted in the ground, the surrounding soil insulates the roots, providing protection from severely cold temperatures. Roots are the least hardy plant tissues, making plants more susceptible to cold damage when planted in containers.

Several years ago I planted two dwarf globe arborvitae in my front pots and they survived a winter that was not excessively cold. However, the next spring I removed these shrubs from the planters so I could plant colorful annuals for the growing season. Plus, I had found it tiresome to water the containers during the winter. Before planting perennial and woody plants in containers, consider that they will need to be watered regularly during the winter to keep the roots from drying out and dying. Also, these plants may succumb to winter cold, but if they do survive and you want to change your container garden display from year to year, they will need to be replanted in the landscape.

I am still in a quandary about what to do with my planters. There are so many possibilities. What should I do? I am tempted to plant some traditional bright yellow mums along with the less conventional veggie garden kale, chard, and herbs. I also like the beautiful variegated foliage of the many new coral bells and Heucherella cultivars. However, I also want to try planting bulbs. I need to make my decision soon before it’s too late to plant anything!

REPOTTING ORCHIDS IS EASIER THAN YOU THINK

GARDEN TIPS – Written by Marianne Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published September 25, 2016

Today, you can go into almost any store that sells houseplants and find blooming orchids available for sale at reasonable prices. Orchids are no longer exotic plants grown only in the tropics or by experts with greenhouses. You and I can grow them fairly easily in our homes, but their care does differ from that of other houseplants.

Most of the approximately 28,000 species of orchids are epiphytes. Epiphytes are plants that grow upon other plants but do not obtain water or nutrients from those plants. In their natural habitat, epiphytic orchids typically grow on tree trunks and branches. They hang onto their hosts with thick aerial roots and utilize those roots to absorb water and nutrients found on the surface of the bark. In addition, these thick roots store water and are capable of photosynthesis.

The roots of epiphytic orchids are covered with a protective spongy layer of dead tissue called velamen. The velamen plays an important role in the absorption of water and nutrients by these aerial roots and it also protects the roots from UV-B radiation. If you remove an epiphytic orchid from its pot, the velamen on the roots will be white when the roots are dry and transparent when moist and full of water.

Because the roots of epiphytic orchids are not typical houseplant roots, orchids cannot be grown in the typical potting media used for houseplants. They require special orchid media that provides conditions similar to those found on the bark of a tree. The media must furnish generous aeration, allow for good drainage, and retain some moisture. There are commercial orchid mixes available containing coarse fir bark and perlite, but orchid experts often create their own mix using a variety of materials that meet the specific needs of their orchids. Experts also use special orchid pots that provide plenty of aeration to the roots. These plastic or clay pots have slots on the sides for aeration in addition to holes in the bottoms for drainage.

Orchids that die at the hands of their owners usually fail either because they were watered incorrectly or they were not repotted when necessary. Orchid roots must have moisture and air. Orchids should be watered whenever the potting mix starts to dry out. When watered, good drainage is essential because orchid roots should not be allowed to sit in water.

Orchid media gradually breaks down and deteriorates, no longer providing the needed aeration. Because of this, orchid experts recommend repotting orchids every two to three years. I was afraid to take on the task of repotting, so my orchids were languishing on my windowsill and appeared to be dying. I had to do something, so two months ago I mustered the courage to repot them.

Repotting was easier than I had imagined. Working over a plastic wash tub, I carefully removed each plant from its pot and gently removed all the old growing media from the roots. Using clean pruning snips, I cut off any obviously dead, shriveled, or mushy roots. I also sterilized the snips between cuts to prevent spreading disease.

I then repotted each plant by wrapping the roots around so they would fit into the clean, somewhat larger orchid pot I had ready for it. I first placed some orchid media in the bottom of the pot and then situated the plant in the pot so that the crown at the base of the leaves was about a half inch from the top of the pot. Once in the pot, I packed fresh dampened orchid media around the roots, using a chopstick to gently push the media into any voids between the roots. I finished by watering the plants to help settle the media around the roots. Now my orchids are looking much better.

FALL LAWN CARE PAYS OFF NEXT SPRING

GARDEN TIPS – Written by Marianne Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published September 18, 2016

This summer was not as hard on area lawns as the past three preceding excessively hot summers, but many area lawns could still benefit from a little attention this fall.

Fall is the most important time of year for fertilizing your lawn. Applications of fertilizer in early September and again in late October to early November are the two most important times of year to fertilize your lawn. Even though grass top growth slows during the shorter, cooler days of fall, grass plants continue to grow sideways by producing tillers that become new grass plants. By fertilizing in late fall, you promote the production of healthy tillers that will result in a denser turf next year.

Fall mowing practices are key in protecting the health of those new tillers that are being formed in the fall. Keep mowing your lawn at the recommended height of 2.5 to 3 inches until top growth slows. After top growth slows to a stop, Kelly Kopp, Utah State University turf grass specialist, recommends gradually lowering the height of the lawn to about 1.5 inches. Leaving lawn grass extra-long in the fall can lead to fungal disease problems over the winter. Cutting the grass very short all at once will damage the established grass plants and the new tillers. Be sure to lower the height gradually.

When it comes to fertilization, lawns do not need a specialized “winterizing” fertilizer containing higher levels of potassium and phosphorus, despite advertisements seen at this time of year. No research indicates that these fertilizers are beneficial to the cool season grasses used for area lawns. When applying fall fertilizers you should be concerned primarily about nitrogen. The last application of fertilizer in early November should have most of the nitrogen in a quick-release form that is readily available to the grass as it begins to go dormant with cold weather. Kopp points out that research shows that late fall fertilization “provides the most benefit and drought tolerance to the lawn the following summer.”

Last year’s heat and drought left many lawns vulnerable to invasion from broadleaf weeds. Prostrate spurges have taken hold in numerous area lawns. These spurges have tiny leaves and form dense, ground-hugging mats. Spurges get started along lawn edges next to pavement or in open spots. Each plant is prolific, producing thousands of seeds. Seeds germinate in early summer, grow quickly, and flower within five weeks of germination. This provides time for more than one generation per year. The good news is that spurges are annual weeds and will die out with frost. Fertilizing and mowing to promote a dense turf will help crowd out the spurges next year.

During the growing season, spurges are difficult to control with herbicides because they are resistant to the typical dandelion broadleaf weed killers containing 2,4 D. The spurges are more effectively controlled with lawn weed control products containing triclopyr. Pre-emergent herbicides applied prior to germination in both lawns and landscape beds can also help in the fight against the spurges.

A fall application of a broadleaf weed herbicide will control most other perennial broadleaf weeds in lawns, such as dandelions, plantain, clover, black medic, and others. The results of a fall herbicide application is often not immediately apparent, but by next spring most of these weeds will disappear. However, there is no need to treat your entire lawn if you only have a few weeds. Treat these individually or pop them out with a weed popper.

Remember, a little attention to your lawn this fall will pay off next spring.

RESEARCH GROUNDCOVERS BEFORE PLANTING

GARDEN TIPS – Written by Marianne Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published September 11, 2016

Do your research first before planting any groundcover in your landscape. Too often a plant that seems to be perfect for the situation, becomes a nightmare or escapes and becomes a noxious weed in native areas. Here are two examples of plants that gardeners often introduce into their landscape and regret it later.

Snow-on-the-Mountain (Aegopodium podagraria): This plant’s other sobriquet, bishop’s weed, should be a clue that it can become a problem. Bishop’s weed, also known as goutweed, is a vigorous ground cover that thrives in shade and is very winter hardy. It is often planted by gardeners as a groundcover beneath trees where dense shade prevents lawn growth. Most gardeners prefer the variegated form of bishop’s weed, but there are also forms with solid green leaves. The plant also produces clusters of white flowers.

The problem is that bishop’s weed truly can become a weed in the yard and garden. It spreads by long branching rhizomes and also readily self seeds, making it difficult to contain within the area it was planted. Once established, it is aggressive and tenacious.

Bishop’s weed is an alien plant. It was supposedly introduced to North America as an ornamental plant by early settlers and was well established in the US by 1863. In some northeastern and mid-Atlantic states it has escaped cultivation and has become an invasive weed that reduces native species diversity. Research indicates that the main dispersal agent has been gardeners.

Heartleaf (Houttuynia cordata): The red-yellow variegated form of this plant is known as the chameleon or rainbow plant. Like the previous plant, heartleaf is a vigorous groundcover with a creeping habit. The leaves, variegated or solid bluish green, make the plant quite attractive. In early summer it produces pretty single white flowers above the leaves. Heartleaf is not drought tolerant, preferring moist conditions and full sun to light shade. It spreads by rhizomes, making it both invasive and doggedly persistent in the garden.

While this plant is quite attractive, it apparently has an odor when crushed or pulled. Fans say it has a delightful citrus or lemon-pepper aroma. Detractors say it is stinky and smells like a skunk or rotten fish. Comments like “Worst plant in the world. Do not plant it.” or “This plant is impossible to kill. It’s totally invasive.” from gardeners on various on-line gardening blogs, should make you think twice about planting it.

Heartleaf is native to Southeast Asia and Japan where it grows in moist, shady areas. It is grown in Asia as a vegetable and both the leaves and roots are harvested for eating. While I could not find that there is any concern about heartleaf becoming a noxious weed in the US, it is definitely considered obnoxious by many gardeners who have planted it.

I was able to find both of these plants on-line for sale from reputable nurseries and recommended as groundcovers by university experts. However, when considering what groundcover to plant, do a little research first. If descriptions indicate a plant is “aggressive,” “vigorous,” or “invasive,” I recommend avoiding it.

Are you interested in planting a groundcover that will not become a nightmare? Visit the Master Gardener Demonstration Garden behind the library at 1620 South Union Street in Kennewick. In parts of the garden you will find some groundcovers that do not become a problem after planting and are well suited to area conditions.

ON THE WATCH FOR JAPANESE BEETLES

GARDEN TIPS – Written by Marianne Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published September 4, 2016

It was never a matter of “if” the Japanese beetle would reach the Pacific Northwest, it was a matter of “when” it would get here. That could be now. Numerous adult beetles have been trapped and found eating on roses and other plants in Portland, according to the Oregon Department of Agriculture (ODA). ODA says that this suggests “a breeding population of the non-native insect has been established.”

Uh oh! This is terrible news for gardeners and growers. A University of Kentucky publication says that “the Japanese beetle is probably the most devastating pest of urban landscape plants in the eastern United States.”

I am willing to bet that if you migrated to this area from the eastern part of the US, you already know too well why a Japanese beetle infestation is scary. As a pest, this rather pretty beetle packs a double whammy. Its grubs feed on grass roots and can be very damaging to lawns. The extremely voracious adults are omnivorous, feeding on a wide variety of plant hosts including roses, ornamentals, trees, shrubs, fruit, and vegetables, often devouring the upper sides of plant foliage, leaving only the skeleton of veins and midribs behind.

The Japanese beetle is one of the scarab beetles and could be considered attractive if you like beetles. The adult beetle is almost ½ inch in length with metallic copper wing covers and clubbed antennae. The head and thorax in front of the abdomen are metallic green. Along the sides of the abdomen are hairy patches that look like white spots.

Like so many damaging insect pests, the Japanese beetle is an alien, coming here from Japan. It was first identified in the eastern US in 1916 and it became established in all the states east of the Mississippi, except for Florida, by 1998.

Besides its rapacious appetite, this beetle’s propensity for aggregating on plants can lead to rapid and complete defoliation of a plant. Japanese beetle-damaged plants emit volatile chemicals that bring more beetles to the party. In addition, the unmated females emit a pheromone to attract even more hungry beetles. Once done with one plant, they move onto another.

Thankfully, there is only one generation of Japanese beetles a year, but with each adult female laying from 40 to 60 eggs, populations can build quickly. Control with pesticide applications is aimed at both the adults on plants and their grubs in the soil. You may see Japanese beetle traps advertised for their control, but university research indicates that the traps are effective in monitoring for the beetle’s presence, but not for control. In fact, the traps can result in more of the beetles finding your yard and causing damage.

Over the years ODA has been working to contain and eradicate any Japanese beetle infestations that they have detected. They believe that the origin of these infestations are air cargo carriers coming in through the Portland International Airport. ODA estimates that the current infestation has been present for more than a year without detection. Right now they are trying to pinpoint where the breeding population is located so they can treat the infestation next year.

For us in Washington, it is good to know that the Washington State Department of Agriculture (WSDA) has been on the watch for the Japanese beetle and has been conducting trapping each year since the mid-1980s to make sure they have not become established anywhere in the state. So far, WSDA has not had to conduct eradication measures on a breeding population yet. I hope it stays that way.

SPIDERS ARE OUR FRIENDS

GARDEN TIPS – Written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Published August 28, 2016

I have to admit that when I relocated to Washington a long time ago, I was deathly afraid of spiders. Since then I have come to appreciate these much misunderstood beneficial arachnids.

Spiders are not insects. They have two body segments, eight legs, and eight eyes. They also have a pair of chelicerae, appendages resembling fangs but serving as jaws. In addition they have a pair of pedipalps, appendages resembling small legs that are used for sensing objects, for helping construct a web, and for holding onto prey. Unlike most insects, spiders do not have antennae or wings, but they are capable of producing silk their entire life.

What makes spiders beneficial is that they prey on insects, providing us with natural pest control. What makes them scary is their appearance and the fact that almost every type of spider is venomous. However, that does not mean they are harmful to us. Generally, most spiders do not possess venom that causes humans any injury. If their venom does cause a problem, it usually just an itchy bite. Out of the approximately 50,000 species of spiders that exist in the world, only about 25 of them are capable of causing human illness and none are considered deadly.

The reason spiders possess venom is to aid them in gaining control over their prey who no doubt try to escape when captured. Spiders are not intent on attacking us and “taking us down” as prey. The most venomous spider in the US is the black widow and it only bites humans when disturbed or threatened.

Spiders take different approaches in capturing their prey which are usually insects. Some build sticky webs and wait for an unsuspecting insect, such as a fly, to become stuck in the strands. As the insect struggles, the spider injects it with venom to immobilize or kill it. Other spiders build webs with dry silk and quickly attack their prey when the vibrating strands alert them of their dinner’s presence. About half of all spider species do not spin webs for capturing prey. Some spiders hunt down their victims, while others sit in hiding to wait for dinner to pass in front of them.

As fall approaches, many homeowners fearful of spiders migrating indoors from outside, will spray their yard and home foundation with pesticide to kill the spiders. This is shameful. Spiders are our friends, eating all sorts of other insects and providing natural pest control just like preying mantids, lady beetles, and other beneficial insects.

This spraying is also misguided because most of the spiders found living inside a home are house spiders, not outdoor spiders. House spiders are ones adapted to indoor conditions that are not favorable to outdoor spiders. House spiders arrive in homes as egg sacs with building materials used to construct the home or on household goods. They spend their lives hidden somewhere within or under the home. When you see them in the early fall roaming about the house, they are in search of females for the purposes of mating.

Outdoor spiders are not well adapted to the limited food and water supply available inside a house. They will stay outdoors, not migrate inside to find a cozy place for winter. They are adapted to surviving winter outdoors. If they get lost and come indoors, they will die.
If you do have a number of house spiders start appearing in your house in the fall, they have come from somewhere within the house. While creepy, it should not cause you sleepless nights. Just buy a bunch of sticky spider traps at the hardware or grocery store and place them along baseboards in the corner of rooms or under the beds. If cobwebs are a problem on the outside of your house or on shrubs, simply brush them off with a broom or use a forceful spray of water to wash them off. Remember, spiders are our friends.

Spiders are much misunderstood creatures. To learn more about spiders go to the University of Washington Burke Museum website that debunks many myths you may have heard about spiders at: http://www.burkemuseum.org/blog/curated/spider-myths

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