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PUTTING THE YARD AND GARDEN TO BED FOR THE WINTER

GARDEN TIPS – written by Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA Written October 25, 2015

I occasionally get asked to give a presentation on “putting the yard and garden to bed for the winter.” Fall garden chores are pretty simple and can be designated as “should-do” and “good-to-do”. I am not sure I could give a thirty minute or longer presentation, but here are the “should-do’s” for fall.

RAKE LEAVES: On the should-should do list is raking leaves. If you have a number of trees like I do, the leaves can certainly pile up. They tend to blow around and pile up at my back door and elsewhere in the landscape. As we start to get more dew and moisture, these leaves can mat down and smother the grass and other plants. Get those leaves raked up and consider using them for making compost or tilling them into your vegetable garden soil where they will decompose over the winter and help improve the soil.

MOW THE GRASS: After the stress of a very hot summer, your lawn needs all the help it can get. You should keep mowing if the lawn is growing. Do not mow the grass extra short and then put the mower away. Also, do not leave it extra long, as this can lead to matted grass and favorable conditions for snow mold. (This past spring snow mold fungus showed up in many area lawns and caused significant damage.) Mow at the recommended height of about 2.5 inches until you no longer need to mow. The good news is that as the weather cools, you will not need to mow as often.

TREAT FOR BROADLEAF WEEDS: If broadleaf weeds, like dandelions or clover, have shown up all over your lawn, now is the time you should treat for these weeds with an herbicide spray. However, if you only have a few of these weeds here and there, dig them out by hand or pop them out with a “weed popper.”

Herbicide sprays for broadleaf weeds will not control grassy weeds. Annual grasses, such as crabgrass will die with a hard frost, and need to be controlled next spring with pre-emergent herbicides or “preventers” that will keep the seed from germinating and growing. Perennial grasses, such as Bermuda grass, are not controlled with fall chemical applications.

DIG TENDER BULBS: Many of the tender bulbs, corms, rhizomes, and tubers that we plant in our gardens, including cannas, calla lilies, gladiolas, and dahlias, are tropical plants from warmer climates (Zones 7 to10) where they can stay in the ground over the winter. In cooler climates (Zones 6 and lower) like ours, they should be dug each fall and stored for the winter in a cool, dry protected location where they will not freeze. Some years in our area these tubers and bulbs may survive if left in the ground and heavily mulched. However, if winter brings severely cold temperatures, they will be killed.

To store them, wait about two weeks after frost kills their tops and then carefully lift the tubers, rhizomes or corms from the soil; shake off as much of the soil as possible; rinse them with clean water; and let them dry in a protected dry spot. Place them in cardboard boxes or paper bags using dry sawdust, wood shavings, or peat moss for packing.

You know, maybe I could give a talk on getting your yard and garden ready for winter. There seems to be a lot to do in the fall. More soon on the “good-to-do” fall garden tasks.

Helping Landscape and Garden Plants Cope with Drought

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

Written April 2, 2015

With the prospect of limited irrigation water in the coming months, we may have to make agonizing decisions regarding which plants in our yards and gardens to save and which plants to let go. To me, it is like making ASophie=s Choice.@  Before making these difficult decisions becomes a necessity, there are some things we can do to make the most of the water that will be available.

As much as 50 percent or more of the water that is applied to bare soil is lost to the atmosphere through evaporation from the soil. The rate of evaporation increases with increasing air temperatures, solar radiation, and wind. In addition, the lower the humidity, the faster the evaporation. By applying a mulch in our landscape and garden beds we can reduce the amount of soil moisture lost through evaporation by as much as 50 per cent, depending on the type of mulch.

For landscape plants and perennial flower beds, I recommend using shredded bark or wood chip mulches applied on top of bare soil and maintained at a depth of 3-4 inches. Bark and wood chip mulches should not be used in vegetable gardens and annual flower beds because they will become incorporated into the soil. This causes a problem because soil microbes will use the nitrogen in the soil for the decomposition process, thereby tying up the nitrogen and making it unavailable to garden plants.

Where annual crops are grown and the soil is regularly tilled or disturbed, organic mulches that break down more quickly are advisable. I recommend applying well-rotted compost, lawn clippings mixed with compost, or lawn clippings as mulches. Keep in mind that the general recommendation is not to collect lawn clippings, but if you do have them available they can be recycled as a mulch. However, you should never use clippings if they have been treated with an herbicide without waiting the amount of time specified on the product label.

Never apply more than a one-inch layer of fresh grass clippings at one time because they mat down and start to decompose anaerobically, making a gooey mess. Instead, wait until the clippings last applied have dried, and then apply another one-inch or less layer. The clippings can be tilled into the soil at the end of the season, adding organic matter to the soil.

To increase the effectiveness of a grass or compost mulches, place one to two moistened sheets of newspaper on top of the soil, overlapping the sheets as you place them in the garden, and then cover the paper with a layer of mulch. (Without a cover of mulch, the newspaper will easily be blown away by wind.) Do not use glossy color sections of newspaper, as they may contain heavy metals or other chemicals that will contaminate the soil. The newspaper will decay over the growing season and then can be tilled into the soil along with the layer of mulch on top.

Rock mulches are suitable for areas vulnerable to wildfires or non-plant areas, but they should generally be avoided around landscape plants because they are heat sinks. The rocks absorb heat during the day and then radiate that heat back at nighttime, increasing the heat stress and water needs of plants. Light-colored and white rock also reflects light back onto plants compounding

WHY NOT LANDSCAPE FABRIC?

written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA
published – SEPTEMBER 19, 2014

WHY NOT LANDSCAPE FABRIC?

When we moved to our new house seven years ago, I had the enjoyable task of starting our landscape from scratch. My plan included a variety of trees in the lawn and plenty of shrubs and ornamental grasses in landscape beds around the house and the perimeter of yard. Adamantly opposed to using landscape fabric or geotextiles, the beds were mulched with a four inch layer of medium size shredded bark after planting.

Admittedly, landscape fabric or geotextiles are better than the black plastic used for mulching landscape beds in the 70s and 80s. They allow for the movement of air and water, where black plastic does not. Even though they do break down with time, geotextiles covered with mulch last longer than the black plastic in the same situations.

So why am so I fervently against using landscape fabric? To make landscape fabric more aesthetically pleasing, it is often covered with a thin layer of mulch. Bark or wood chip mulches decompose with time, creating material in which weeds can grow. While rock mulches do not break down, blown in dust can create a layer of soil where weeds can grow. Plus, landscape fabric does break down with time, especially when not covered with a thick (3-4 in) layer of mulch that blocks UV radiation.

Many gardeners who have used landscape fabrics will tell you it is not a permanent solution to weed control. Weeds will invade the beds, and then the fabrics become a nightmare, especially when Bermuda grass and field bindweed (wild morning glory) are involved. The roots or rhizomes of these trailing pernicious weeds find their way into the fabric fibers, making it impossible to rogue them with pulling. If you do try to pull them out, the fabric comes with them. Arrrgh!

The best way to control weeds in landscape beds is with organic mulches. I prefer the look of shredded bark, but wood chips are just as effective and less expensive. WSU Extension Horticulturist, Dr. Linda Chalker Scott, prefers wood chips because of some of the problems that bark shredded bark can pose. She favors wood chips because of the possible contamination of bark with salt or weed seeds and because of the sharp, pointed fibers of softwood bark are not “gardener friendly.” Plus bark can resist water penetration because of the waxes they contain.

Whether you use bark or wood chips as a mulch, the layer should be 4-6 in thick. This blocks light from getting to the soil and helps maintain soil moisture. I do advise keeping mulch away from directly around the base of trees and shrubs. It retains moisture and excludes air. A thick layer of mulch touching a plant’s base can lead to collar rot causing serious damage to trees and shrubs.

Chalker-Scott points out that if you are trying to reclaim a site or an area with serious perennial weed problems consider using a 8-12 in thick layer of wood chips. She cautions you to taper down to a very shallow layer close to trees and shrubs.

Mulching with bark or wood chips is not a place-it and forget-it situation. They decompose with time, adding organic matter to the soil. Periodically you will need to add fresh mulch on top of the old, to maintain the weed controlling 4-6 in layer, being careful to keep the mulch away from the base of plants. By the way, fall is a great time to renew the bark or wood chips in your landscape.

Published: 9/19/2014 12:27 PM

Using Landscape Fabric

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

GARDEN TIPS – SEPTEMBER 19, 2014 – WHY NOT LANDSCAPE FABRIC?

When we moved to our new house seven years ago, I had the enjoyable task of starting our landscape from scratch. My plan included a variety of trees in the lawn and plenty of shrubs and ornamental grasses in landscape beds around the house and the perimeter of yard. Adamantly opposed to using landscape fabrics or ‘geotextiles,’ I mulched the beds with only a four inch layer of medium-size shredded bark after planting.

Admittedly, landscape fabrics or geotextiles are better than the black plastic used for mulching landscape beds in the 70s and 80s. The fabrics allow for the movement of air and water, where black plastic did not. Even though they do break down with time, fabrics covered with mulch last longer than black plastic in the same situations.

So why am I fervently against using landscape fabrics? To make landscape fabrics more aesthetically pleasing, they are often covered with a thin layer of mulch. Bark or wood chip mulches decompose with time, creating material in which weeds can grow. While rock mulches do not break down, blown in dust can create a layer of soil where weeds will also grow. Plus landscape fabrics do eventually degrade, especially when covered with only a thin layer of rock or bark mulch that does not block UV radiation well.

Many gardeners who have used landscape fabrics will tell you they are not a good solution to long-term weed control. Weeds will invade the beds and then the fabric becomes a nightmare, especially when Bermuda grass or field bindweed (wild morning glory) are involved. The roots or rhizomes of these trailing pernicious weeds find their way into the fabric fibers, making it impossible to rogue them out with pulling. If you do try to pull them out, the fabric comes with them. Arrrgh!

The best way to control weeds in landscape beds is with organic mulches. I prefer the look of shredded bark, but wood chips are just as effective and less expensive. Dr. Linda Chalker Scott, WSU Extension Horticulturist, prefers wood chips because of problems associated with shredded bark. She favors wood chips because of the possible contamination of bark with salts or weed seeds and because the sharp, pointed fibers of softwood bark cause tiny slivers in gardeners’ hands. In addition, bark mulch may resist water penetration because of the waxes and lignins contained in bark.

Whether you use bark or wood chips as a mulch, the layer should be 4-6 in thick. This blocks light from getting to the soil, preventing weed growth. The layer also helps retain soil moisture. I advise keeping mulch away from direct contact with the base of trees and shrubs. A thick layer of mulch touching a plant bases can lead to collar rot causing serious damage to trees and shrubs.

Chalker-Scott recommends applying a 8-12 in thick layer of wood chip mulch if you are trying to reclaim a landscape site with a serious perennial weed problem. She cautions you to taper down to a very shallow layer close to trees and shrubs.

Mulching with bark or wood chips is not a ‘place-it and forget-it’ situation. They both gradually decompose, adding organic matter to the soil. This is good. Periodically you will need to add fresh mulch on top of the old to maintain the weed controlling 4-6 in layer, being careful to keep the mulch away from the base of plants. By the way, fall is a great time to renew the bark or wood chips in your landscape.

Published: 10/9/2014 2:40 PM

IT’S HOT FOR PLANTS TOO

written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

Can you believe the sweltering weather our region has been enduring? With predictions of continued intense heat, health experts have been warning us about the dangers of this weather and telling us what precautions to take… drink plenty of water, don’t over exert yourself, and try to stay indoors.

Hot weather is not only stressful to us, it’s also stressful to our garden plants. Unfortunately, there’s not a lot we can do to help our plants “beat the heat” other than checking the soil and making sure it stays moist.

You may think you’re applying plenty of water to your plants, but the water may not be reaching deep enough. To check, I recommend about six hours after watering that you use a trowel or shovel to check the soil for moisture.

When checking the soil moisture, consider that soil should be moist to a depth of 24 to 36 inches for trees and large shrubs, 18 to 24 inches for moderate sized shrubs, 12 to 18 inches for small shrubs, perennials, vegetables and annual flowers. Especially during this long spell of extreme heat, you’re likely to find that you need to irrigate your lawn, landscape and garden for longer periods of time and more frequently to keep the soil moist.

Here are some other ways to help your plants cope with the hot weather:

1. Apply an organic mulch to decrease the evaporation of moisture from the soil surface. An adequate layer of organic mulch can reduce evaporation from the soil by as much as 70 per cent.

Organic mulches, like bark and compost, protect plant roots from damaging temperatures by reducing soil temperatures below the surface as much as 10 degrees. Rock mulches absorb heat, raising soil temperatures in the root zone. In addition, rock mulches hold and then radiate heat at night, increasing plants’ water needs. Light colored rock mulches reflect light back onto plants, also causing additional water demands on a plant.

2. On a hot, dry summer day a mature tree can use as much 100 gallons of water per hour or 2400 gallons per day! Because trees use more water during hot weather, you should apply more water. Trees and shrubs have deeper roots than your lawn and need deep watering. Short, frequent irrigation of the lawn can not provide adequate amounts of water to your trees. It’s bothersome, but you should hook up a soaker hose and use it to give your trees and shrubs a deep watering once a week during the summer.

3. When you deep water your trees, keep in mind that the water absorbing feeder roots of established trees are not located at the base of the trunk. Instead, they’re located from the drip-line of the canopy outward, extending as much as 1.5 the diameter of the canopy past the drip-line.

4. Container gardens and raised bed plantings dry out more quickly than “in-ground” plantings because of the reduced soil volume and the soil mixes. Check the soil in these situations and water when needed. You may find you’ll need to water more than once a day during the hottest times of the summer.

It’s looks like the hot weather is going to continue, so make sure both you and your plants have enough water to drink!

Published: 8/1/2009 10:01 AM

BARK VS. ROCK MULCHES

written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

I have long been a strong advocate for the use of bark mulch in the landscape. Looking at the Herald archives I found a column that I wrote back in 1996 about mulches. Back then, lava rock was the predominant rock mulch gardeners were using. I thought it was extremely ugly and wasn’t reticent about sharing my opinion. I also thought the less common river rock wasn’t aesthetically pleasing either. Thank goodness that the “abominable” lava rock is not as popular today.

If you look around newer area neighborhoods there are a variety of different mulches used from bark… to river rock… to crushed basalt, and even fancier crushed rock of a variety of tones and colors. While I still don’t like lava rock, I’ve become accustomed to these other types of rock mulches and don’t find most unattractive. (I suppose that’s fainthearted praise.) However, I still urge gardeners to use bark mulches over rock mulches in the everyday landscape.

Why Not Rock?

We live in a very hot climate. Our recent record breaking temperatures point that out very clearly. Most of the trees, shrub, and other plants that we typically plant in our landscapes are not well adapted to the hot summer temperatures, intense sun, and low humidity experienced here. Rock mulches work against our plants by raising the temperatures around the plants because of their reflectivity, especially light colored stones. Rock mulches also serve as a heat sink because of their heat retention properties Both of these factors lead to increased water demands and stress on landscape plants not native to a hot summer climate.

It’s not just the temperatures around the plants that are raised. Soil temperatures under rock mulches can rise to root damaging extremes during very hot sunny weather. Not all university research substantiates this argument as results seem to vary, but much of the research has not been done in regions with extremely hot, dry summer conditions. I don’t believe that rock mulches are a problem in areas with more moderate climates than ours. Because of their reflectivity and heat sink property they’re probably a plus in areas with long cool springs where spring soils take a long time to warm up… like on the west side of the Cascades.

However, there are a few other problems associated with rock mulches, especially in our wind-prone area. Windblown soil (dirt and dust) and plant debris accumulates over time in rock mulches, decreasing the attractiveness of the darker types of rock and allowing weed seeds to germinate and grow in this new layer of soil deposited between the rocks and the landscape fabric mulch often placed below the rocks to prevent weeds from growing. (I know of one dedicated gardener who removed all his old lava rock, washed it, and then replaced it. There’s a very hard worker. )

If you mulch your home with a rock mulch, you should also realize that not only does it keep temperatures warmer around your plants, but it also keeps your house and outdoor living areas warmer than bark mulch, turf, or ground covers. Of course, the same is true that it will provide you with some warming during the winter.

Why Bark?

So why am I such a fan of shredded bark mulch? Shredded bark gradually decomposes, adding organic matter to the soil. This helps retain soil moisture and nutrients and also feeds beneficial soil microorganisms. Because it slowly decays, periodical renewal applications will be needed.

Bark is not highly reflective and minimizes the amount of sunlight that’s reflected back on tree and shrub trunks and crowns. Because of it’s moisture holding ability, it also tends to cool the area around plants rather than acting as a heat sink and stressing plants. As already pointed out, bark mulch keeps the soil and roots cooler than rock mulches in hot weather.

Overtime, bark does a better job of controlling weeds. Really! To accomplish this goal, bark should be applied to weed free soil surfaces, not over the top of landscape fabric or over the top of persistent perennial weeds, such as Bermuda grass or bindweed. Bark mulch can be very effective controlling weeds if a four-inch (six inches if bark nuggets or extremely course bark is used) layer is applied. This takes some advance planning to make sure your landscape beds are graded to make a four-inch thick layer possible. It’s also helpful to use some sort of edging around the beds, whether applying bark or rock, to contain the mulch. Special note: It’s important to keep both bark (because of moisture) and rock (because of heat) about six inches away from the base of trees and shrubs.

Finally, I think bark has a more natural look, providing the most attractive setting for the landscape plants. I’m not surprised that I still prefer bark to rock, but I wish I could convince more gardeners that it’s the best mulch to use in this hot climate of ours. The only exception is for homeowners who are vulnerable to wildfire. In these areas rock mulch makes sense, hot or not.

Published: 7/5/2008 1:49 PM

THINGS GARDENERS SHOULD KNOW

written by Marianne C. Ophardt WSU Extension Faculty for the Tri-City Herald, Kennewick, WA LANDSCAPE FABRIC: Twenty years ago, many area landscapes were mulched with black plastic and rock mulches. This combination made it particularly tough to grow trees and shrubs successfully. The black plastic didn’t allow for the free movement of water and air into the soil. Plus, the plastic combined with the rock mulches increased soil temperatures and greatly stressed plants. The black plastic didn’t last indefinitely and weeds became a problem again before long. Eventually ‘geotextiles’ came along and started to replace the troublesome and restrictive black plastic. These woven or spun materials allowed for the free movement of air and water. They also were effective in reducing germinating weeds. Today, geotextile landscape fabrics have become the standard in landscaping, but they have not been the ultimate answer to weed management. Landscape fabrics do have some drawbacks. First, they do degrade over time, especially when exposed to sunlight. Ones that are UV resistant will last longer. Usually a top layer of mulch is applied over the fabric, increasing its life and the appearance of a landscape bed. If an organic mulch (my preference) is used on top of the fabric, eventually the mulch starts to decompose and will become colonized by weeds. Weeds are kept out longer if inorganic rock mulches are used… but eventually weeds will show up whether organic or rock mulches are used over the fabric. Removal of weeds in these situations is made difficult because the weeds’ roots grow into the fabric. Also, the roots of landscape plants tend to grow near the soil surface and grow into the fabrics. When the fabric breaks down and removal is desired, plant roots are damaged. While the use of geotextile fabrics can deter weeds for a some time, it’s better not to use them. They don’t provide permanent weed control in permanent landscape situations. Organic mulches, such as shredded bark, coarse compost, or wood chips, are the best choice for managing weeds in home landscape beds. They are attractive, their decomposition nurtures beneficial soil organisms, and their breakdown helps improve the soil. PRUNING PAINT: ‘Wound dressings’ or ‘wound paints.’ have been around for years and have been used by conscientious, caring gardeners trying to keep their plants healthy. It was thought that these wound dressings would stop wood rot and prevent the entrance of decay organisms and boring insects when painted on tree wounds. Unfortunately, the various wound dressing preparations do just the opposite. Wound dressings seal in moisture, actually creating a better environment for the decay organisms. Some of the materials used delay callus formation and the closing of the pruning wounds, increasing the amount of decay that can occur. They can also increase the amount tissue damage at the wound site, increasing the overall injury. Plus, these materials do eventually dry out and crack, making it easy for pathogens to find their way in. The use of wound dressing has not been recommended by tree care professionals and horticulturists for many years. Products containing collagen, pectin, hydrogel, and aloe gel have all been touted in recent years as natural compounds that will enhance tree healing. Unfortunately, there is no evidence that these new materials or the old materials hasten healing or prevent decay. The best way to promote healing of pruning wounds is to make proper pruning cuts and then leave the wound open to light an air. For other physical wounds to trunks, it’s important to make a smooth edge to the wound and leave it open to air and light. There is no good reason to apply a wound dressing or wound paint to pruning cut, trunk injuries, or cracks in the trunk. PHOSPHORUS FERTILIZERS AND FLOWERING: No doubt you have seen specialized fertilizers on the garden store shelf. Some of these are ‘formulated’ to promote flowering of annuals and flowering shrubs, such as roses. Most of the flower enhancing fertilizers contain higher levels of phosphorus. You can probably find a good number of references and web sites that recommend the application of phosphorus fertilizers to promote flowering, but the truth is that extra applications of phosphorus will do no good if there is an adequate level of phosphorus already present in the soil. Most of our local garden soils have adequate levels of phosphorus, especially if someone has applied fertilizers containing phosphorus in the past. Phosphorus does not readily leach out of the soil, as does nitrogen. By applying excess phosphorus you will decrease soil health. By decreasing soil health, you decrease plant health. Weaker plants are more subject to attack from diseases and insects and susceptible to nutrient deficiencies… setting up a greater dependency on chemicals. So don’t add extra phosphorus from flower promoting fertilizers unless you know your soil is deficient in this nutrient. Is your soil deficient in phosphorus? Get a soil test done to find out. LAWN MOWING: Mowing… it’s the most tedious lawn task, but it’s also one of the most important. Mowing at the right height, the right frequency, and the right way go a long way to providing you with a nice looking, healthy lawn that’s able to resist invasion by weeds and attack by pests. Kentucky bluegrass lawns mowed too high will develop thatch more quickly and will lose a nicely manicured look. Mowing too low is even worse than mowing too high. Low mowing decreases the leaf surface area, decreasing the photosynthesis needed for plant growth. This leads to weaker grass plants with shallower, weaker root systems. This makes the grass plants more prone to stress from possible drought and heat stress during the summer. The recommended mowing height for Kentucky bluegrass lawns in our region is 2 to 2.5 inches. Lawns should be mowed often enough so that no more than 1/3 of the leaf blade is removed at any one mowing. ‘Scalping’ the lawn by removing more than 1/3 of the leaf blade will injure and weaken grass plants. If you go away on vacation and the lawn gets away from you, mow first at the highest height you can achieve on the mower. Once those clippings are dry, mow again at the recommended height in a different direction. (However, it would be better to have someone mow in your absence.) For the best looking lawn, mow your lawn in a different direction every one or two mowings. Mow at right angles to the previous mowing. If you always mow in the same direction, the grass will have a tendency to be pushed in that direction and it won’t stand up well. Be sure to keep your mower blade very sharp. Dull blades tear the ends of the grass, which weakens the grass plants by damaging more leaf tissue and leaves a lawn with an off-color, less manicured appearance.

Published: 6/4/2005 1:40 PM

INTERNET TERMITE HOAX

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

You may have already read or heard about the dire warnings being circulated on the internet alerting gardeners about cheap mulch being sold by home improvement stores. This low-priced mulch supposedly comes from Louisiana and is infested with Formosan termites. These alerts seem to have spread almost as quickly as a computer virus or an insidious computer worm. Gardeners around the country are extremely concerned. Fortunately, this warning is basically a hoax… a myth… the beginning of a new urban legend.

Let’s look at the facts in this situation. The Louisiana Commissioner of Agriculture and Forestry, Bob Odom, points out that his department has quarantined woody debris being removed from termite infested areas. In the quarantined areas contractors are mulching and hauling the waste to approved landfills withing the infested areas.

Each parish (county) in the quarantined areas must first submit a plan for the treatment of the wood before it can be moved out of the area. The Louisiana Department of Agriculture and Forestry is making sure the quarantine is being observed and their invasive pest expert has contacted the stores mentioned in the e-mail warnings regarding the use of such wood in their mulches.

Odom says, ‘In my opinion, someone is using the Internet to cause hysteria about a problem that doesn’t really exist. If there are people out there who know about someone violating the quarantines, then they need to report it to us. We’ll shut the culprits down real quick but it has to be reported.’ He added , ‘I think the quarantines are doing the job, though. We’ve worked with the debris contractors, the Corps of Engineers and FEMA to handle the debris and quarantines.’

I’d like to point out that it doesn’t make much sense for the home improvement stores mentioned in the warnings to ship chipped wood all the way from Louisiana to Washington state or other distant locations. Given the cost of shipping, due to high oil prices, it’s likely the mulch wouldn’t be very ‘cheap’ once it arrived in stores here. It would be much more cost effective to use waste chipped wood and bark from trees in the Pacific Northwest. Also, most gardeners in the region use shredded bark or bark nuggets for mulching, not chipped wood.

Out of curiosity you might want to know about the Formosan termite, sometimes dubbed the ‘super termite.’ It’s a non-native species of termite that is believed to have entered the U.S. sometime after World War II on military ships through southern ports of entry, including New Orleans and Lake Charles in Louisiana, Charleston in South Carolina, and Galveston and Houston in Texas.

The Formosan subterranean termite, Coptotermes formosanus Shiraki, is extremely destructive. One of the things that makes this non-native termite so destructive is the size of its colonies. While native subterranean termites tend to have colonies of about one million termites, the Formosan termite colonies may reach a size of eight million. Like other subterranean termites, the Formosan termites feed primarily on wood, but also on other cellulose containing materials such as cardboard and paper. While they don’t eat other types of materials for nutrition, they will chew their way through insulation board, thin lead and copper sheeting, plasters, asphalt, and some types of plastic in search of food and moisture. While rumored to chomp their way through concrete, they don’t. However, they are very adept at finding their way through tiny cracks and fissures in concrete and mortared walls.

So far, the Formosan termite has only been found in Alabama, southern California, Florida, Georgia, Hawaii, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, and Texas. The cost of control of these destructive pests and the repair of their damage is extremely high. Their destruction has already cost residents of New Orleans over one billion dollars.

This super termite may have entered the U.S. on ships and become established in port regions, but it has been unwittingly spread to other areas by gardeners in infested potted plants, railroad ties and landscape timbers and trees. So while there is no substantive truth in the internet warnings, it’s not a bad idea to think about the things you can do to prevent subterranean termites, either native or non-native, from becoming a problem.

Here are some tips:
– Don’t store wood, cardboard or paper in such a way that these materials are in direct contact with the soil. This also includes wooden planters, posts, tubs, trellises and firewood. When possible anchor wooden posts in cement so that the wood is not in direct contact with the soil.

– Don’t stack firewood close to your house.

– Inspect any wooden items, such as railroad ties, wood mulch, or landscape timbers, before buying them and placing them in your landscape.

– Keep mulch, landscape plants, and wooden structures one foot or more away from the foundation of your home. Don’t use wood chips as a mulch around your home’s foundation.

– Termites need moisture. Fix leaky outdoor faucets and water lines. Slope the landscape away from the house so precipitation and irrigation water drains away from the house. Prevent sprinklers from wetting the walls of your house or other wooden structures. Fix any leaks which can create damp conditions, such as drain drips or roof leaks.

– Look and dispose of any wooden stakes or scrap wood left behind in the soil from construction projects.

– Get rid of any dead wood in the landscape, especially the roots and stumps of trees and shrubs that have been removed.

In the next month or so our native western subterranean termite will be swarming or flying about for the purpose of reproduction and establishment of new colonies. To the untrained eye winged termites look like winged ants. If you suspect you might have a problem with termites, bring a sample of the offending creatures to the Benton County WSU Extension office in Kennewick (5600E West Canal Drive) and we’ll tell you if its ants… or termites.

If you want to know more about termite detection, prevention and control in Washington, you can find the WSU Extension Bulletin ‘Termites” available at no charge on-line at http://cru.cahe.wsu.edu/CEPublications/eb0787/eb0787.pdf.

Published: 3/11/2006 9:01 AM

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