The Greene Thumb. UT Extension Greene County. Thousand Cankers Disease... Is the Master Gardener Program for You?

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1 September 2010 Volume 2, Issue 7 Special points of interest: Thousand Cankers Disease Fall Gardening Tips Celebration of Mountain Culture 2011 Master Gardener Class Schedule Accepting Applications for Winter 2011 Master Gardeners! All classes will be held at the Greene County Extension office on Tuesday and Thursday mornings! 9:00 am -12:00 pm beginning February 1st and ending March 24th A light breakfast will be served. The fee for the class is $140.00! Applications can be picked up at the Extension Office or downloaded off the Greene County Extension webpage! UT Extension Greene County The Greene Thumb Is the Master Gardener Program for You? Do you have an interest in serving in any of the following volunteer areas: civic organizations, the elderly, youth groups? Do you have the desire to share the joy of gardening with others? Do you want to teach others more about nature and their environment? If you answered yes to any of these questions, please join our Master Gardener Program! Thousand Cankers Disease... First occurrence of Thousand Cankers Disease of Black Walnut east of the Mississippi: On August 5, 2010, the Tennessee Department of Agriculture announced the occurrence of thousand cankers disease in black walnut trees (Juglans nigra) in Knox County, Tennessee. Although this lethal disease has been present in western states for at least a decade, it had not previously been reported in the native range of the black walnut east of the Mississippi River. The presence of this devastating disease in the eastern part of Tennessee poses a great risk to black walnut trees in Virginia. Virginians should be on the lookout for this disease in black walnut trees. General information on thousand cankers disease: Thousand cankers disease is caused by the newly named fungus Geosmithia morbida, which is vectored by the twig beetle, Pityophthorus juglandis. When the beetles form galleries beneath the bark of walnut trees, they carry the fungus with them. The fungus forms dark cankers in the phloem around the beetle galleries. The number of beetles that attack an individual tree is enormous and the number of cankers that form is correspondingly large. Cankers coalesce and eventually girdle the trunk and branches, killing the tree. The host range of the fungus and its vector is limited to walnut species. Symptoms of thousand cankers disease: Despite the graphic name of this disease, cankers are not the most obvious symptom. Initial symptoms of infection may be subtle. Leaves may flush in spring, but then suddenly wilt. Gradually the upper branches die back. Cankers are hidden beneath the bark and can only be seen in the early stages of disease when a thin layer of bark is cut away. A dark brown (continued on page 2)

2 September 2010 The Greene Thumb Page 2 Canker Disease continued... stain is apparent in the phloem just beneath the outer bark. The discoloration does not extend into the xylem (the wood), so care should be taken to avoid cutting too deep when examining trees for cankers. Beetle galleries are also present in affected phloem tissue and tiny exit holes may be present, especially in branch crevices. Beetles are approximately 2 mm long, so exit holes are very small and may be hard to see. Affected trees eventually die. Trees typically die about two years after the first symptoms are noticed, but this may be years after the initial infection actually occurred. Trees may resprout the base, but sprouts are also infected and killed. History of the disease: Thousand cankers disease was first identified in 2001 in infested black walnut trees in Colorado; however, mortality in black walnut stands was observed in Oregon in the presence of twig beetle afar back as the 1990 s, so the disease was likely present earlier than Both the beetle and the fungal pathogen are thought to be native to North America, so the epidemics that occurred in black walnut at that time were not the result of an introduced species. On the contrary, the epidemic in black walnut is thought to be due to an expansion of the twig beetle s host range, which followed the introduction of the black walnut, an eastern species, to western states. Previously, Arizona walnut (Juglans major) was the main host of the twig beetle and the canker disease did not occur on this host species. The discovery of thousand cankers disease in black walnut in Colorado raised the strong risk that the disease and its vector could be introduced to the native range of the black walnut, east of the Mississippi. Such an introduction could easily occur through transport of infected wood, especially infected firewood. The lack of resistance in the native population of black walnut could mean rapid spread of the disease in the eastern forest. The introduction of both the vector and the fungal pathogen (most likely via firewood or logs) has now been confirmed in Tennessee. Preventing the spread of thousand cankers disease: Currently there are no known control measures for thousand cankers disease of black walnut. Because transport of firewood is one of the main avenues for spread of the disease, several states including Tennessee, have enacted quarantines restricting the movement of black walnut firewood. The movement of timber and nursery stock is also restricted by these quarantines. Education of the public about the need to prevent the transport of firewood is also of paramount importance. To prevent the spread of thousand cankers disease: Don t transport firewood. If you are camping, buy firewood from a local source. Similarly, firewood from the camping location should NOT be transported home. Leave any extra firewood at the camping location. Don t buy firewood from an unknown source. If you purchase firewood from a door-to-door vendor, make sure you know where the firewood comes from. If it is not from a local source, don t buy it, and make sure you educate the vendor about the potential for transporting lethal plant pathogens and insect pests on firewood. Watch for symptoms of thousand cankers disease in your black walnut trees. If you suspect your black walnut tree may have thousand cankers disease, contact your local county Extension agent for more information. (continued on page 3) Large trunk cankers of black walnut associated with Fusarium solani. Walnut twig beetle, top view.

3 September 2010 The Greene Thumb Page 3 Canker Disease continued... Tips for field diagnosis: Look for clusters of dead or dying black walnut. Look for dieback in the tops of black walnut trees. If you can clearly see the sky through the canopy, there is dieback in the tree. Carefully slice away a thin layer of bark on the trunk or branches of suspect trees. If you notice meandering beetle galleries or a dark brown stain in the phloem, the tree is suspect. Cankers caused by the fungus Geosmithia morbida (photo by Ned Tisserat, courtesy of Bugwood Network). or the cankers. Try to get branches that have beetle holes or galleries. Do not remove the bark on branches for submission. Underlying wood often discolors naturally when bark is removed and this can make the cankers difficult to detect. Place branch samples in two ziplock-style plastic bags and submit the sample to your local county Extension office html for mailing to the VT Plant Disease Clinic. You will be asked to complete a diagnostic form for mailing with the sample. Please take time to fill out the form completely. If you find small, dark brown beetles less than ¼ long, place them in alcohol in a vial, complete an Insect ID form and submit the sample to the county Extension office for mailing to the VT Insect ID Lab. different in appearance from thousand cankers disease cankers. With Neonectria canker, the bark naturally sloughs away from the surface of the cankers and the sunken cankers are very visible. Edges of Neonectria cankers also typically have ridges of callus tissue that form each year and older Neonectria cankers have a target-like appearance. Phytophthora collar rot is a disease caused by an oomycete pathogen that attacks the tree at the soil line. Dark brown discoloration occurs under the bark, but is only present at the base of the tree, whereas with thousand cankers disease, the cankers are present all over the tree. Further information: The following web sites also have information on this disease: s/walnutthousandcankersdisease.pdf Twig beetle galleries in cankered black walnut wood (photo by Whitney Cranshaw, courtesy of Bugwood Network). Sampling black walnut for thousand cankers disease: (Note that this disease is only known to affect black walnut.) Cut affected, but still live branches or sections of branches that are at least 1 inch in diameter. Smaller branches rarely have the beetles Diseases that could be confused with thousand cankers disease: Environmental stresses, such as frost injury or drought, can cause dieback in black walnut, as well as other tree species. Mechanical damage to the base of the tree by lawnmowers or soil moving equipment could cause dieback in black walnut, as well as other tree species. Neonectria canker, a different fungal disease that occurs on black walnut, could be confused with thousand cankers disease, but cankers caused by the Neonectria fungus are very Note that this disease is an emerging situation. We will send out updates as we acquire more information on this disease. Virginia Tech College of Agriculture and Life Sciences Department of Plant Pathology, Physiology and Weed Science Mary Ann Hansen and Elizabeth Bush, VT Plant Disease Clinic Gary Griffin, Forest Pathologist, Department of Plant Pathology, Physiology and Weed Science

4 September 2010 The Greene Thumb Page 4 Fall Gardening Tips... Plant cool season vegetable crops now that will mature into the later fall months. These include Chinese cabbage, turnips, kale, mustard, spinach, lettuce, carrots, and beets. Keep seedlings and transplants well watered and mulched. Spinach and lettuce seeds may germinate poorly in warm soils and should be sown heavily to compensate. When planting fall vegetables, be aware that more time will be required to bring the crop to maturity because of reduced light and ambient temperatures. Add at least 2 weeks to the days to maturity number on your seed packets. Plan to cover your fall garden crops in September with a floating row cover or cold frame to further extend the harvest period. Be sure to fertilize seedbeds, keep the soil moist and protect seed-lings from pests. Consider building a cold frame or using floating row covers to extend your fall harvest. Cover crops of oats, winter rye, winter wheat and crimson clover can be sown now through the middle of October. Seeds should be in close contact with soil to promote germination. Your cover crop will protect your soil, conserve soil nutrients and add or-ganic matter and nutrients when tilled in next spring. You can also sow your cover crop in walkways between beds. Plant garlic now through the end of October for a July 4 harvest. Select the largest cloves from the largest heads. Plant the cloves root end down; space them 4-6 inches apart and cover with 1-2 inches of soil. Mulch the garlic bed with fallen tree leaves after the green leaves emerge. Do not use store bought garlic for planting because of the significant risk of introducing white rot, a devastating fungal disease. If your winter squashes and pumpkins are full-sized, fully colored and the rind is hardened, cut them from the vine leaving a 4-5 inch handle and store in a cool location until ready to use. Gourds should be harvested after a hard frost. (continued on page 5) Blackgum and sumac are turning red fall is coming! Chestnut oak acorns and white oak acorns begin to fall. Hummingbirds begin migrating south. Young black rat snakes have hatched and are emerging. Monarch butterflies migrate south.

5 September 2010 The Greene Thumb Page 5 Fall Gardening Tips... Dig storage potatoes on a cloudy, warm day after plants begin to die back. Let them lay on the ground for a few hours before bringing them inside. They should not be washed, washing increases the chance of rot in storage. Store potatoes in a dark, cool location (35-40 F.) Sweet potatoes should be harvested the same way except that it helps to cure the roots for days in a warm, dark location (85 F.). Curing helps to heal over cuts and scrapes before being stored for the winter in a cool, dry location (55 F.) Sunflowers can be harvested when the backs of the flowers are dry. Cut the stalks one foot below the flower head, tie them to-gether and hang upside down in a cool dry place. Cooler temperatures and shorter days will cause tomatoes and other warm season crops to ripen unevenly and be less flavorful. You may also notice seeds inside of tomato fruits beginning to germinate. This is a natural phenomenon and will not affect eating quality. Full size green tomatoes can be brought indoors to ripen. They ripen more quickly if placed in a paper bag with a banana or apple. The ethylene gas released from the banana or apple will help to ripen the tomatoes. Cabbage loopers, imported cabbageworms, crossstriped caterpillar, harlequin bugs, cabbage aphids, and cabbage flea beetles are feeding on members of the cabbage family. They can be handpicked or sprayed with Bt (for the loopers, worms and caterpillars) or try covering crops right after they are planted with a floating row cover. Propagate herbs by stem cuttings. Cut six-inch stem pieces and remove all but the top leaves. Dip the lower ends in rooting hormone and insert the stems into a moist and loose, soil-less media. Cover the pot with a perforated plastic bag and keep outside in a protected location. Pull gently on the stems in two weeks to test for root growth. Pot the cuttings up individually after they start growing and bring them indoors for use during the winter. Harvest the individual leaves of tarragon, rosemary, basil, sage and other culinary herbs and dry them indoors. Herb leaves are most intensely flavored right before the plant blooms. Snip foliage in the morning after the dew has dried. To dry down herbs for storage, tie the cut stems together and hang them upside down in a dry location. Cover with a paper bag to avoid losing the shat-tered leaves. Store dried herbs in glass jars away from light and heat.

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7 September 2010 The Greene Thumb Page 7 GREENE COUNTY MASTER GARDENER 2011 CLASS SCHEDULE DATE TOPIC INSTRUCTOR Tuesday, February 1, :00 AM 12:00 PM Tuesday, February 8, 2011 Thursday, February 10, 2011 Tuesday, February 15, 2011 Thursday, February 17, 2011 Tuesday, February 22, 2011 Thursday, February 24, 2011 Tuesday, March 1, 2011 Thursday, March 3, 2011 Tuesday, March 8, 2011 Thursday, March 10, 2011 Tuesday, March 15, 2011 Thursday, March 17, 2011 Tuesday, March 22, 2011 Thursday, March 24, 2011 Time To Be Announced Welcome & Introduction Orientation Soils Wildlife Entomology/Insects Organic Gardening Basic Botany/Interior Plants/Ornamentals Landscape Design Turfgrass & Lawns Pesticide Safety & Pesticides Small Fruits & Pruning Demonstration Weeds Plant Pathology Herbs Vegetable Gardening Graduation!!! Melody Rose Extension Agent - Greene County To Be Announced To Be Announced Mannie Bedwell Extension Agent - Hamblen County Jeff Martin Organic Extension Grad Student - UT Hugh Conlon Extension Area Specialist Ken Soergel Master Gardener Washington Co. Dr. Tom Samples, Professor UT Extension, Plant Sciences Dept. Melody Rose Extension Agent Greene County Dr. David Lockwood, Professor UT Extension, Plant Sciences Dept. Chris Ramsey Extension Agent Sullivan County Keith Hart Extension Agent Carter County Joy Moore & Sandee Grimes UT Master Gardeners Melody Rose Extension Agent - Greene County Location To Be Announced Total Fee, including Master Gardener handbook: $ Checks payable to UT Extension - Greene County Final payment due: Monday, January 3, 2011 Reach out to the people of Greene County and share your knowledge and love of gardening! Upon completion of the training, give 40 hours of community service back to your local community or participate in other beautification and industrial efforts here in Greene County. You have one year to give back 40 hours of service to your community. Choose projects you enjoy! Choose projects that benefit your community! This can be achieved through various activities you want to see accomplished in your local community.

8 September 2010 The Greene Thumb Page 8 Felder Rushing Gathering in the Garden Lecture Thursday, September 16th at 7:00 P.M. Kingsport Renaissance Center, 1200 Center Street in Kingsport Felder Rushing to Present Programs in Kingsport: Renown horticulturist and prize-winning author Felder Rushing will present two programs in Kingsport. The 10th generation southern gardener known for his offbeat garden designs and humorous presentations will deliver the annual Gathering in the Garden lecture on "Slow Gardening - Getting the Most Out of Your Garden in All Seasons, Using All Your Senses". With stunning photography and a down home approach filled with humorous anecdotes and zany observations, Rushing will help gardeners learn to garden for the long haul, to focus on seasonal rhythms, to choose plants most appropriate to local conditions, and to sit back and actually enjoy their gardens. Sponsored by Southern Appalachian Plant Society, this program is free and the public is invited. Copies of Felder's books will be available for purchase and signing. Earlier in the day Rushing will present a workshop on "Growing Cool-Season Edibles in Pots" from 10:00 a.m. - 12:00 noon at Evergreen Home and Garden Showplace, 1413 Riverport Road in Kingsport. In this hands-on workshop, perfect for September, participants will learn how to grow vegetables and herbs in containers and will take home a pot filled with an assortment of cool weather edibles. Fee for the workshop is $25 for SAPS members ($45 for non-members) and includes all materials plants, container, and potting medium. To reserve a place, mail check, payable to SAPS, to: Joy Moore, P.O. Box 87, Fall Branch, TN Registration is limited. Deadline is September 13. Sorry, no cancellations or refunds, but we will save the materials for you if you have to cancel. For more information on either program, call or jnjmoore@embarqmail.com. A retired Extension Service urban horticulture specialist, Felder Rushing is author or co-author of 15 books (including Passalong Plants and Tough Plants for Southern Gardens) and has had thousands of gardening articles published in syndicated newspapers and in regional and national garden magazines, including Garden Design, Horticulture, and the National Geographic. Rushing s quirky cottage garden, overstuffed with heirloom plants and "yard art", has been featured in many TV programs and magazines (including the cover of Southern Living). This distinctly non-stuffy board member of the American Horticulture Society currently hosts a gardening program on NPR affiliate stations and gives over a hundred lectures a year, coast to coast and overseas. You can visit Felder Rushing at:

9 September 2010 The Greene Thumb Page 9 Calendar of Events... Sat.-Mon., September 4-6 Archie Campbell Days Bulls Gap, TN (423) Monday, September 13, 2010 Lawn Shortcourse with Dr. Tom Samples 6 p.m. - 8 p.m. Greene County Extension Office Conference Room $10.00 registration fee. Monday, September 13, 2010 Deadline to register for the Felder Rushing workshop at Evergreen Garden Center in Kingsport. Call Joy Moore at 423/ Tuesday, September 14, 2010 Fall Home Gardening Workshop 6 p.m. - 8 p.m. Greene County Extension Office Conference Room $10.00 registration fee. Thursday, September 16, 2010 SAPS Hands-On Workshop Growing Cool Season Edibles in Pots with Felder Rushing at Evergreen Garden Center, 1413 Riverport Road in Kingsport. 10 A.M. to Noon. Learn to grow gourmet greens, vegetables, and herbs in pots and take home a pot filled with cool weather edibles. Call 423/ Thursday, September 16, 2010 SAPS Meeting: Annual Gathering in the Garden - Lecture with Felder Rushing at 7:00 P.M. Fri.-Sun., September Rhythm & Roots Reunion Bristol, TN bristolrhythm.com Sat. - Sun., September 25 & 26, 38th Fall Folk Arts Festival Exchange Place Living History Farm, 4812 Orebank Road Kingsport. 10 A.M. to 5 P.M. on Saturday and Sunday from noon until 5 P.M. The festival will focus on harvest time activities on an 1850s farm with emphasis on pioneer arts and crafts, ole timey foods, music, children s activities and living history reenactments. Artisans will demonstrate and sell a wide array of traditional fold arts, and the Harvest Market will feature plants, autumn produce and seasonal crafts. Admission is $1 for adults and 50 for children. For more information call 423/288/6071. Fri.-Sat., October 1-2 Apple Festival Unicoi, TN unicoicounty.org Fri.-Sun., October 1-3 National Storytelling Festival Jonesborough, TN storytellingcenter.net (423) Sat.-Sun., October 9-10 Cranberry Festival Shady Valley, TN johnsoncounty.tn.org (423) Sunday, October 17 Chillin and Grillin Greeneville, TN greenecountypartnership.com (423) The 7th Annual Aussie Fall Fest Chillin' N Grillin' offers crafts, food, entertainment, a Karaoke competition and features a Chili Cook Off competition and a BBQ and Wings Cook Off on Saturday, October 30 from 8 a.m. to 7 p.m. Back again this year will be the Kids' Q which will give the youngsters ages 15 and under the opportunity to compete as well as the Backyard Cookers that will feature "first-time grillers and participants." September 2010 S M T W T F S The University of TN and the Big Spring Master Gardener Association will host the 2011 Master Gardener classes beginning February 2011 at the Greene County Extension Office.

10 September 2010 The Greene Thumb Page 10 Greeneville Farmers Market 2010 Greene County Fairgrounds, Greeneville, TN The Greeneville Farmers' Market has been providing a venue for local producers for more than a decade. The Greeneville Farmers' Market is a producers'-only market, meaning that vendors at the market must have produced themselves any items they offer for sale. This ensures that the produce, meats, cheeses, breads, plants, flowers, crafts and prepared foods at the market are produced locally, and that customers can talk directly to the person responsible for growing their food about production methods. Open Every Saturday at 6:00 a.m. & Tuesday at 2:00 p.m. The Greeneville Farmer s Market is dedicated to providing Greene County a sustainable outlet to obtain fresh, locally grown food, agricultural products and quality handcrafted items, while promoting community interaction through education and entertainment events." Visit for more details on these and other calendar events. Growing Great Gardeners in Greene County! Melody Rose, Extension Agent UT Extension, Greene County 204 North Cutler Street Suite 105 Greeneville, TN Phone: (423) Fax: (423) mtrose@utk.edu We re on the Web!! The University of Tennessee Extension is an off-campus division of the UT Institute of Agriculture. It is a statewide educational organization, funded by federal, state and local governments, that brings research-based information about agriculture, family and consumer sciences, and resource development to the people of Tennessee where they live and work. Because Extension emphasizes helping people improve their livelihood where they are located, most Tennesseans have contact with UT Extension through their local county Extension agents found in each of the 95 counties. Extension agents are supported by area and state faculty as well as by the educational and research resources and activities of the United States Department of Agriculture (USDA), 74 land-grant universities, and 3,150 county units throughout the nation. The stated mission of the system is to help people improve their lives through an educational process that uses scientific knowledge to address issues and needs.