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Oak Disease Pathogen Found in Southern Calif. Nursery

The California Oak Mortality Task Force, during a March 17, 2004 meeting at Sonoma State University, announced that Phytophthora ramorum, a fungus that causes sudden oak death (SOD) was found on camellias at Monrovia Nursery, in Azusa, just east of Los Angeles. It's reportedly the first time the disease has been identified in a Southern California nursery.

Said to be the largest horticultural nursery in California, Montrovia Nursery has been in business for 76 years and produces more than 2,200 varieties of perennials, conifers, woody ornamentals, shrubs, trees, citrus, camellias, rhododendrons, vines, ferns, grasses and topiaries. Other than the home nursery in Azusa, it also operates nurseries in Dayton, Oregon, Visalia, California, Springfield, Ohio, La Grange, N.C. and Cairo, Georgia. These wholesale nurseries, covering some 4,724 acres, ship plants to more than 5,000 garden centers nationwide.

The California Department of Food and Agriculture has the job of trying to identify any potentially infected material that might been shipped unknowingly in the last year. The disease has reportedly been found in more than 40 plant species worldwide.

All host plants at the Monrovia Nursery are to be inspected and plantings within 10 meters of infected plants will be on hold for 90 days and inspected. The pathogen was reportedly traced from shipments from a Washington state to Southern California.

The California Oak Mortality Task Force reports that coast live oak (Quercus agrifolia), tanoak (Lithocarpus densiflorus), and California black oak (Quercus kelloggii) are dying in large numbers in central coastal California due to SOD. The fungus affects many other tree and shrub species, including rhododendron species, California bay laurel (Umbellularia californica), huckleberry (Vaccinium ovatum), and California buckeye (Aesculus californica). There are 38 species susceptible to the fungus, 22 of which are identified as hosts by the USDA. (The list is available at The plants most likely to be spread the fungal infection are the California bay laurel, Oregon myrtle and Rhododendron spp.

The task force had confirmed back in October 2002 the presence of the pathogen in at least 12 California counties. The infection may occur on the trunk and branches (cankers) or on leaves (leaf spot). Infection does not necessarily result in death of the plant, the task force points out; mortality occurs when the cankers expand in the truck.

The fungus thrives in cooler, wetter climates. In California, it is found only in the coastal counties.

Blood Testing Required for Washington Workers Who Handle Pesticides

On December 3, 2003 the Washington Department of Labor and Industries adopted a new regulation that requires employers provide blood testing for agricultural workers who handle specific pesticides including Guthion, Supracide, Cygon, Sevin, Vydate, Temik and similar products known as toxicity category I or II organophosphate or N-methyl-carbamate cholinesterase-inhibiting pesticides. The rule applies to workers who handle these pesticides for 50 or more hours in any 30-day period.

Provisions of the new rule require employers to keep records of the hours employees spend handling these toxic pesticides, to provide blood testing for pesticide handlers, to train workers on the new law's requirements, to halt workers from handling these pesticides when medically necessary and to protect a worker's wages and benefits for up to three months if blood tests identify potentially harmful cholinesterase suppression in their system.

Cholinesterase is an enzyme critical to the function of the nervous system. These pesticides interfere with the function of cholinesterase by causing it to decrease, leaving nerves in the body over stimulated to the point of exhaustion, which can lead to symptoms ranging from blurred vision, diarrhea and tremors, to seizures, loss of consciousness and even death.

The Department of Labor and Industries began this rulemaking last year as the result of a Washington state Supreme Court decision. The new rule was adopted Dec. 3 and becomes effective Feb. 1, 2004.

For complete information on the new rule, log on to the Labor and Industries website at or call 800-423-7233.

Coqui Croaking Not the Only Cause for Consternation

Eleutherodactylus coqui, a Caribbean native that leap frogged from Puerto Rico to Hawaii, is said to be threatening the nursery industry.

Perhaps you've never had the pleasure of listening to hundreds of frogs croaking in unison during a mating frenzy on a Hawaiian isle. This scribe has. Strolling by a pond at dusk in the presence of a female of the homo sapian variety, we heard a few frogs croaking, then dozens, then hundreds. Taken aback by the sheer volume of noise, then bemused, then laughing, then pleased to have shared this experience on a warm, tropical evening.

That memory was dredged up from 1976. Today in Hawaii, the islanders are hearing a different frog song, this from the Eleutherodactylus coqui, a Caribbean native that apparently leap frogged from Puerto Rico to Hawaii via nursery plants in transport. The coqui, as it is called in Puerto Rico, is a cute little frog that comes in a variety of colors (green, brown, yellowish) and sometimes with dorsal stripes. It's one to three inches in length, has suckers on its toes but no webbing between the toes or fingers, a biological adaptation, as it is doesn't pass through the tadpole stage. The coqui emerges from the egg fully formed, although about the size of a pencil point. This adaptation is critical, because the coqui doesn't need a pool of water to lay its eggs, which limits the spread of normal frogs. The female lays about 100 eggs a year, which develop within 17-26 days. The Smithsonian magazine reports that in some Hawaiian locals there are more than 6,000 coqui per acre, five times the yield in Puerto Rico, where snake and spiders keep the coqui population in equilibrium. Environmentalist are concerned that the coqui will wipe out some insect populations that some birds rely on, and may promote the growth of such invasive species as rats and snakes.

Some people are fans of the coqui, but many are disturbed or irritated by the shrill mating calls of the male, whose amorous screeching rates between 70-90 decibels, a noise described by many as "unbelievable." The decibel scale is logarithmic; each 10-decibel increase represents a tenfold increase in noise. The Columbia Encyclopedia explains that a 10-decibel increase is perceived as doubling the loudness; 30 decibels is 10 times more intense than 20 decibels and sounds twice as loud; 40 decibels is 100 times more intense than 20 and sounds four times as loud; 80 decibels is one million times more intense than 20 and sounds 64 times as loud; 45 decibels of noise keeps most people from sleeping; traffic noise is about 70 decibels to a pedestrian on the sidewalk. Hearing damage begins at about 85 decibels.

Rita Beamish reported in The Smithsonian that one nursery owner "nearly lost his business, despite spraying," due to the frogs on his plants. Also quoted was Jamie Runnells, vice president of the Big Island Association of Nurserymen, who categorized the situation as the "biggest single problem facing the nursery industry on the Big Island."

Realtors are urging clients to spray their properties, and the state is looking into pest control options (caffeine spray induces coqui hear attacks). As with all pest control efforts, there are concerns about damaging the plants and other wildlife. Many at this point are thinking in terms of containment, not eradication.

Landscape Superintendent's Challenge:
5,000 Acre Campus

Texas A&M’s signature tree, sprawling at the center of the campus, is dubbed the Century Oak and dates back to the school's opening in 1876.

COLLEGE STATION, Texas– Christoph Wieland wrote in 1768: "Too much light often blinds gentlemen of this sort. They cannot see the forest for the trees."

The old saw could apply to the Texas A&M University campus, home to 5,000 acres of land with an estimated 25,000 to 30,000 trees.

We don't' know if Tom Dew, A&M's landscape superintendent and Koby Weatherford, the campus urban forester, can see the forest for the trees, but they certainly see the trees, as they have catalogued 11,261.

"You name the tree, and we probably know about it," landscape superintendent Tom Dew told the Aggie Daily, referring to the 90 different tree species found on the Brazos County campus.

Not all the trees are native, as some of the school's early horticulturists planted trees like the Kentucky coffee, the Jerusalem thorn, the western soapberry, the Kawakami pear, the Chinese pistache, the Carolina laurel and the Afghan pine.

Still, the venerable oak is the most common type found on campus, Dew specified, although there are 14 different types, including the sawtooth, chinkapin, shumard, bur and ness oak, and six species of elm, four of maple, plum and pine, and three of holly.

Dew and Weatherford are part of the school's four-person tree management department, which is also responsible for growing about 150,000 plants each year on campus.

Texas A&M, the state's first public institution of higher education, opened in 1876 as the Agricultural and Mechanical College of Texas. The school's most prominent oak, located in the heart of the campus, is older than the college. An oak that died in 2002 was determined to be 130 years old after its rings were counted. The biggest threat to the campus oaks is disease, oak wilt and oak decline, a problem affecting the central Texas area.

On display at the entrance to Texas A&M is a huge ATM logo composed of alternanthera, all derived from cuttings from the one planted at the site in 1968. Coleus cuttings from the 1960s have been passed on through the decades to provide stage plants used at every Texas A&M commencement ceremony for the past 35 years.

John Deere Landscapes University to Expand Regional Seminars

Jim Houston, PBA,CPE, explained how to price landscape and irrigation projects at a recent John Deere Landscapes University program

The attendance at recent John Deere Landscapes University seminars has prompted the company to offer the programs to more regional markets in the coming year, according to Damian Zawacki, national training manager. More than 500 participants attended the winter programs in Atlantic City, Charleston, South Carolina, and Biloxi, Mississippi.

The classes and workshops are three day programs: attendees generally sign up for six to seven classes. Two and four-hour courses are offered in landscape irrigation; lighting and water gardening; business and management; drainage and erosion control; turfgrass maintenance; brick paving; snow removal and other subjects.

Programs include prominent speakers, such as Jim Houston, whose most recent book is How to Price Landscaping & Irrigation Projects; John Allin, who explains profitable snow removal; and Scott Evans, who specializes in H-2B/ (H-2B is a program created by the U.S. Department of Labor to allow immigrants to temporarily work in the U.S. to fill nonagricultural jobs in which U.S. workers are in short supply.

Attendees receive diplomas, complimentary breakfasts and lunches. The enrollment fee was $299 for each three-day event, or "20,000 John Deere Landscapes Partners Program Points."

For more information, visit


Oh, Deere, that's good news!

"Net income more than doubled last year...the board has voted to raise the dividend. As a result, the quarterly dividend rate on Deere Stock is being increased 27 percent, to 28 cents a share, payable May 3. This brings the indicated dividend rate on an annualized basis from 88 cents a share to $1.12."–Robert Lane, chairman, CEO, Deere & Co., at the Feb. 25, 2004 annual meeting of shareholders.

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