VOL. 47/NO. 1
Spring 2017
The Official Publication of The Kentucky Nursery and Landscape Association
Top Landscape Weeds and Management Strategies
Plant Disease Diagnosis: Making the Most of Your Resources
Snapshots from KNLA’s
2017 Spring Training & Showplace
VOL. 47/NO. 1
spring 2017
Top Features
7 Upcoming Event
ark Your Calendars, M and Save These Dates!
10 Cover Story
Top Landscape Weeds and Management Strategies
Departments
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Feature Story
10
lant Disease Diagnosis: P Making the Most of Your Resources
20 Recent event
Snapshots from KNLA’s 2017 Spring Training & Showplace, January 25–26
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6 From the President, Kim Fritz 6 Welcome, New knla Members! 8 News from KNLA 22 Index of Advertisers
Nurs ery Views • spri ng 2017
20 The Kentucky Nursery and Landscape Association serves its members in the industry through education, promotion and representation. The statements and opinions expressed herein are those of the individual authors and do not necessarily represent the views of the association, its staff, or its board of directors, Nursery Views, or its editors. Likewise, the appearance of advertisers, or their identification as Kentucky Nursery and Landscape Association members, does not constitute an endorsement of the products or services featured in this, past or subsequent issues of this bi-annual publication. Copyright © 2017 by the Kentucky Nursery and Landscape Association. Nursery Views is published bi-annually. Subscriptions are complimentary to members of the Kentucky Nursery and Landscape Association. We are not responsible for unsolicited freelance manuscripts and photographs. Contact the managing editor for contribution information. Advertising: For display and classified advertising rates and insertions, please contact Leading Edge Communications, LLC, 206 Bridge Street, Franklin, TN 37064, (615) 790-3718, Fax (615) 794-4524. 4
The official publication of the Kentucky Nursery and Landscape Association
P.O. Box 5006 l Frankfort, KY 40602-5006 502-330-8300 Email: knla.org@gmail.com • info@knla.org www.knla.org • www.thelandlovers.org KNLA Officers President Kim Fritz Village Green Wholesale Nursery 4251 Bloomfield Road • Springfield, KY 40069 Tel: 502-460-0764 villagegreenwholesalenursery@yahoo.com Vice President Michael Mueller Inside Out Design, LLC 100 Old Georgetown Road • Frankfort, KY 40601 Tel: 502-695-7020 • mike@insideout-design.org SECRETARY Stephanie tittle (2019) 4716 Greenhaven Lane Goshen, KY 40026 Tel: 502-303-4852 • wfarmgarden@gmail.com TREASURER Cora Martin (2018) Ammon Nursery, Inc. 6089 Camp Ernst Road • Burlington, KY 41005 Tel: 859-586-6246 • cmartin@ammonplants.com
Past President Martin Korfhage Clinton Korfhage Nursery, Inc. 1823 Heaton Rd. • Louisville, KY 40216 Tel: 502-448-1544 • martinlndscp1@aol.com martin.korfhage@korfhage.com Directors Pat Carey (2018) Riverfarm Nursery 2901 N. Buckeye Lane • Goshen, KY 40006 Tel: 502-228-5408 • patc@riverfarm.com
Published by Leading Edge Communications, LLC
206 Bridge Street l Franklin, TN 37064 615-790-3718 l Fax: 615-794-4525 Email: info@leadingedgecommunications.com www.leadingedgecommunications.com
Jeff Moore (2018) Signature Landscapes, LLC 1084 Baker Lane • Nicholasville, KY 40356 Tel: 859-887-2735 jmsignaturela@windstream.net Jeff Wallitsch (2018) Wallitsch Nursery & Garden Center 206 Hikes Lane • Louisville, KY 40218 Tel: 502-454-3553 • jeff_wallitsch@live.com
Eric Garris (2018) Bernheim Arboretum & Research Forest P.O. Box 130, Hwy. 245 • Clermont, KY 40110 Tel: 502-955-8512 • egarris@bernheim.org
Educational Advisors Dr. Winston Dunwell UK Research & Education Center P.O. Box 469 • Princeton, KY 42445 Tel: 270-365-7541, ext. 209 wdunwell@uky.edu
Brent Grunfeld (2018) Monrovia 7504 Knight Lane • Fairview, TN 37062 Tel: 615-584-0116 • BGrunfeld@monrovia.com
Dr. Dewayne Ingram University of Kentucky, Horticulture Dept. N-308F Agri. Sci. Center • Lexington, KY 40546 Tel: 859-257-8903 • dingram@uky.edu
Wes King (2018) King’s Gardens 4560 Nicholasville Road • Lexington, KY 40515 Tel: 859-272-7077 • wes@kingsgardens.com
Dr. Robert (Bob) E. McNiel (Emeritus) Highland Moor 226 Shady Lane • Midway, KY 40347 Tel: 859-509-2719 • rmcniel@highlandmoor.com
FROM THE PRESIDENT l Kim Mike Fritz Dreisbach
A Super Start
to Another Growing Season Hello!
I hope everyone has had a busy and profitable season! It was wonderful to see so many of you at the Kentucky Nursery & Landscape Association (KNLA) Spring Training and Showplace! Whether you attended, exhibited or sponsored — Thank You! Photos, including the entire group picture, are included on pages 20–21 in this issue of Nursery Views. There is some fantastic news about next year’s event — see page 21! We are thrilled to welcome Stephanie Tittle to the KNLA board of directors and unbelievably proud of Dr. Winston “Win” Dunwell on being inducted into the KNLA Hall of Fame! Read more about Stephanie and Win on the next pages. Congratulations to our newest Kentucky Certified Nurserymen: Katrina Kelly with Eartheinm in Lexington, Ben Wilson with Alexander’s Lawn & Tree in Richmond and Cody Domenghini with Eastern Kentucky University in Richmond! You should have received “Save the Date” notice for our 2nd Annual Bus Tour on August 17 and the Summer Retreat and Marketplace on September 21! The Bus Tour was fantastic last year, and this year promises to be loads of fun. On August 17, we will meet and tour Boone Arboretum and then hop on a bus to visit the Cincinnati Zoo and Botanical Garden where we will tour and have lunch. After the Zoo, we will ride in comfort to Ammon’s Nursery for our final tour. All tickets are only $99 for KNLA members and $129 for non-members. And, we have been assured that there will be CEUs! There are still sponsorships and room on the bus; however, spots are filling fast, so visit KNLA.org soon to reserve your spot! The Summer Outing, largely sponsored by Proven Winners, will be held at Springhouse Gardens in Nicholasville, KY, on September 21. This promises to be a fantastic event, with two classes being held every hour throughout the day, a delicious lunch, many LA, Arborist and Pesticide CEUs and a great opportunity to informally visit with our sponsors and exhibitors. Cost is only $99 for members and $129 for non-members. Visit KNLA.org to sign up! Wishing you a successful year!
Kim Fritz
Nurs ery Views • spri Spri ng 2017
2016–2018 KNLA President Phone: 502-460-0764 Email: villagegreenwholesalenursery@yahoo.com Snail Mail: 4251 Bloomfield Rd., Springfield, KY 40069
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Welcome, New KNLA Members! Bones Transportation P.O. Box 80 Ottowa, KY 66067 lisa@bonestrans.com M&J Landscape Design Group 325 Jeffiers Lane Taylorsville, KY 40071 landscape@mandjlandscape.com TowerView Farms Garden Center and Landscape 12523 Taylorsville Road Louisville, KY 40299 towerviewfarm@gmail.com United Landscape 729 Bellaire Avenue Lexington, KY 40508 sem@unitedlandscape.net
Upcoming event
August 17 KNLA’s 2nd Annual Bus Tour Meet at and tour Boone Arboretum (9190 Camp Ernst Road, Union, KY 41091). The bus trip will visit the Cincinnati Zoo and Botanical Garden where we will tour and have lunch. After the Zoo, we will ride to Ammon’s Nursery for a tour.
KNLA Member Cost: $99 Non-Member Cost: $129
September 21 KNLA’s Summer Outing Learn and earn to flourish your business! Springhouse Gardens 185 W. Catnip Road Nicholasville, KY 40356
KNLA Member Cost: $99 Non-Member Cost: $129 Nur sery Views • Spr ing 2017
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news from knla
Meet Your New Director, Stephanie Tittle S
tephanie Tittle is the horticulturist at both Woodland and Hermitage Farms, and she grows the produce sold at the Woodland Farm Store. Her horticulture career began when she was a student at Kentucky Technical College. She has worked in the industry for more than 20 years, beginning with greenhouse production, and then a strong interest in propagation — grafting, in particular — shifted her interest to nursery production. A graduate of the University of Kentucky with a BS in Plant and Soil Science, she has been with Woodland Farm since 2007. Born and raised in Pewee Valley, KY, Stephanie lives in Louisville with her husband and three dogs. 2
Congratulations to
Dr. Win Dunwell,
Our Newest Inductee to the KNLA Hall of Fame
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Dr.
Winston Dunwell, Professor of Horticulture for Nursery Crops, was inducted into the Kentucky Nursery and Landscape Association Hall of Fame on January 25, 2017, at the annual KNLA Spring Training Conference. Dunwell has worked with Kentucky’s nursery, arborist and landscape industry since he started at the University of Kentucky Research and Education Center at Princeton in 1979. He has also been awarded the Southern Nursery Association Researcher’s Conference Porter Henegar Memorial Award for Contributions to Environmental Horticulture Research, and he has been named an International Plant Propagator’s Society Fellow: Eastern North America. He continues to find working with the green industry and his many colleagues rewarding and interesting. He and the UKREC Horticulture Group (Dwight Wolfe, Dr. Zenaida Viloria, Daniel Becker, June Johnston and Ginny Travis) are working to integrate new technology into plant production, specifically soil moisture monitoring using sensors connected to wirelessly controlled irrigation systems. This year, their focus is on production of blueberry plants and blueberry fruit production in containers with the PlantPoint irrigation-control system. 2
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FROM THE PRESIDENT l Mike Dreisbach
Four KNLA Members Earn
KY Nurseryman Certification
Three
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Nur sery Views • Spr ing 2017
new candidates have received Kentucky Nurseryman certification for 2017: • Cody Domenghini, Eastern Kentucky University, Richmond, KY • Katrina Kelly, Earthheim, Lexington, KY • Ben Wilson, Anderson Lawn & Tree, Richmond, KY The Kentucky Certified Nurseryman designation helps consumers locate trained professionals who are knowledgeable on plant identification, proper plant usage, keeping plants healthy and pest-free, soils, turfgrass management, landscape design and proper planting and maintenance of nursery stock. The KCN examination is administered each January at the KNLA Spring Training and Showplace. Anyone may obtain the KCN training manual and take the exam. To be granted KCN status, an individual must have worked 6 months full-time or 500 hours parttime in a nursery, garden center or other landscape industry firm. Candidates who successfully complete the test must file for certification and provide signed work-experience statements from their employers. They are required to sign an agreement to abide by the rules and regulations governing a Kentucky Certified Nurseryman, as established by the certification committee. For more information, visit KNLA’s website at www.knla.org/kcn. For questions about the KCN exam, contact KCN Exam Chair, Dr. Winston Dunwell, Extension Nursery Crops Specialist, at the University of Kentucky College of Agriculture, at wdunwell@uky.edu. 2
Cover Story
Top Landscape and Management Strategies Nurs ery Views • Spri ng 2017
In
the nursery and landscape industry, weeds are one of the few certainties. Wet, dry, cold or hot, you will have a weed situation that requires management. Weed management can be more difficult in the nursery and landscape industry than in other agricultural enterprises simply because of the complex nature of the environment. In a monoculture, such as corn or soybeans, it is relatively easy to select weed-management tools that will not harm the crop. In a diverse landscape situation — where there may be annuals, perennials, grasses, shrubs and trees — it is more complex. The tools that can be used that do not harm one specific plant in the design may not be able to be used because of other sensitive vegetation.
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I always encourage professionals to use an integrated weed-management strategy. Integrated weed management is similar to integrated pest management in that decisions are made while keeping in mind the most economically and environmentally sustainable strategy. While herbicides may be a tool that is used, it isn’t the only tool, nor is it necessarily the first tool that should be selected. Cultural and mechanical methods should also be considered. You can consistently rely on some weeds that will require a management strategy. Dr. Winston Dunwell, Horticulture Professor at UK-PREC, shared a list of the most troublesome weeds from a survey that he conducted in 2011. Based on the results of the survey and conversations with others in the industry,
I will address some general management strategies. These weeds are pretty evenly split between grass or grass-like plants and broad-leaved weeds. Some are annuals, and some are perennial.
Proper identification is key The first step in managing weeds effectively is proper identification that also provides the scientific name. As taxonomists improve their methods of classification, there may rarely be some disagreement between sources on scientific name of the plant. Several good resources are available. For a small book that can be left in the shop or the truck, I like Weeds of the Northeast by Uva, Neal and DiTomaso. Weeds of the South and Weeds of the
FROM THE PRESIDENT l Mike Dreisbach Photo
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Weeds
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By Shawn Wright, Horticulture Specialist, University of Kentucky
Photo 1. Wild garlic (Allium vineale). Photo 2. Annual bluegrass (Poa annua). Photo 3. Dandelion (Taraxacum officinale).
to take a photograph that can be sent to the county ANR agent for assistance in weed ID. Technology is continually improving, and there may be some good weed-identification apps, but I have not yet found one that I particularly like. Here are a few key points to keep in mind when dealing with weed management: • Healthy crops are important; proper fertilization and watering can increase the competitiveness of the crop. Weeds are often “weedy” because they are good at capturing limited resources
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Midwestern United States and Central Canada are also good books available through University of Georgia Press. The Southern Weed Science Society has produced a DVD, the Interactive Encyclopedia of North American Weeds, that is excellent and is available through the society http://www.swss.ws/. The USDA-NRCS has a tremendous database of plants — at https://plants. usda.gov/java/ — that can help to confirm the identification of a plant. Virginia Tech University has an excellent website http:// oak.ppws.vt.edu/~flessner/weedguide/. The Weed Science Society of America at http://wssa.net/wssa/weed/weedidentification/ also has a nice website. One of the most convenient tools is your cellphone. Most phones can be used
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Photo 4. Purple deadnettle (Lamium purpureum). Photo 5. Common chickweed (Stellaria media).
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(nutrients, water, space, light) better than other plants. • Sanitation is critical. Remove weeds from the landscape, not just the ground. Some weeds have the ability to set seed even after being pulled out of the ground, so if you just leave them lying there, you haven’t necessarily solved the problem. Weeds that surround your landscape or production facility are often a source of weeds. Look around to see where weeds may be coming from, and try to keep those areas clean. Dirty equipment can also spread weeds. Work the cleanest areas first and then the more weedy areas. Use a hose or leaf blower to clean up your equipment before moving to other locations. • Use a combination of methods to control weeds. If you rely on only one management tool, you are selecting for weeds that are resistant to that management method. This is how herbicide-resistant weeds develop. • Pre-emergent herbicides do not kill seeds. They form an herbicidal barrier that kills the newly germinated weed. If you disturb that herbicide layer in the soil through cultivation, hoeing or other means, you will allow weeds to germinate. • Post-emergent herbicides may be selective (killing only certain species) or non-selective (killing all plants). These herbicides are used after the weed has emerged from the soil. Contact postemergent herbicides kill only the tissue they contact, whereas systemic postemergent herbicides can move through the plant and into the actively growing points away from the site of application. • The label is the LAW! It is important to make sure that the chemical you use is labelled for the site, plant/ crop and pest. A good source for most herbicide labels is http://www.cdms.net/ label-database. Check that the label is current for use in Kentucky. To check for current pesticide registrations, you can go to the National Pesticide Information Retrieval System (at http:// npirspublic.ceris.purdue.edu/state/ state_menu.aspx?state=KY), and enter an EPA registration number, active ingredient or product name.
• Calibrate your sprayers and spreaders more than once a season. Underapplication yields poor results, and over-application can result in damage to non-target species and could be a violation of the law. • Where trade names are used below, no endorsement is intended, or criticism implied, of similar suitable products not named.
COMMON WEEDS Yellow nutsedge (Cyperus esculentus) is one of the world’s worst weeds. A perennial sedge, it has long, grass-like leaves and a three-sided stem. From early summer to fall, a single plant can produce many tubers at the end of the rhizomes, which can give rise to new plants the following year. Nutsedge is not as shade tolerant as some weeds, so a dense canopy can help suppress it, and herbicides such as Sedgehammer can be effective. Johnsongrass (Sorghum halpense) is a perennial grass that can be troublesome in landscapes where the rhizomes have spread through flooding. The prominent white mid-rib on the leaf is a key diagnostic feature. Johnsongrass can be difficult to control after the rhizomes have formed, and they can begin forming within a few weeks of seed germination. It is important to prevent seedling establishment, but once plants are established, lateseason applications of glyphosate can help, as the herbicide is translocated with the carbohydrates to the root system. Nimblewell (Muhlenbergia schreberi), a
warm-season perennial grass that spreads through stolons, is more tolerant of shade than many weeds. While it can be confused with bermudagrass, nimblewell has a tough, wiry stem and four veins on the leaf blade that can aid in identification. In cool-season turf, Tenacity can selectively remove nimblewell.
Wild garlic (Allium vineale) and wild onion (Allium canadense) are two closely related perennials. Wild garlic (see Photo 1) is more commonly found in Kentucky
cover story l continued
and has round, hollow leaves and can be distinguished from wild onion, which has flat, solid leaves. These plants do not have a lot of leaf surface for herbicide absorption so managing these with herbicide treatments often takes repeated applications over more than one season. Metsulfuron is an herbicide that may be included with turf fertilizers and has been shown to have activity against wild garlic. There are also annual grasses that are commonly found in nursery and landscape settings. Prevention is one of the key methods for managing these weeds. If they are controlled before they set seed, they do not generally survive for more than one year, and any infestations must come from new seed entering the site. However, if these plants are allowed to set seed, they can be a problem for many years since weed seeds often can remain dormant for years before germinating. The old saying — One year’s seeding equals seven years of weeding — is based on reality.
The foxtails (Setaria sp.) are summer annual grasses found throughout Kentucky and are often recognized by the large soft, cylindrical seedhead that gives the plants their common name. These seedheads can produce thousands of seeds in a single season, so it is important to control foxtail before it goes to seed. Green foxtail is probably the most commons species in weedy lawns and urban wastelands; yellow foxtail and giant foxtail are less common. Foxtails are not tolerant of shade, so taller mowing heights and the use of a pre-emergent herbicide like Pendulum can be used to manage these weeds.
Crabgrass (Digitaria sp.) is a very common summer annual weed that begins germinating about the time when forsythias bloom or when soil temperatures reach about 56ºF. This is another weed that is fairly shade intolerant, so higher mowing heights will suppress its growth. Excess phosphorus fertilization seems to promote the growth of crabgrass,
so do not over fertilize. Pre-emergent herbicides have been shown to be effective in controlling this weed when applied prior to seed germination. In most of Kentucky, that time is before the first of April.
Goosegrass (Elusine indica) is a summer annual often called silver crabgrass, but it is in a different genus. It is easy to recognize since the leaf bases are silvery white and flattened, and they radiate out from a central point. Unfortunately, this is one of the most difficult annual grasses to control. It grows equally well in dense turf and open areas. Goosegrass has significant genetic diversity that can result in selection of herbicide-hesistant populations or populations adapted to extreme conditions. Annual bluegrass (Poa annua) is an interesting weed. There are two subspecies of the plant, one of which is perennial. The canoe-shaped tip of the leafblade is a key identification characteristic.
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Photo 6. Mouseear chickweed (Ceratstium vulgarum).
Prevention is a key management tool for this weed. Once established, it can be difficult to manage because it is very tolerant of low mowing heights and can produce seeds readily (see Photo 2). Annual bluegrass is drought susceptible, so deep watering less frequently will help discourage the growth of this weed. Preemergent herbicides like Betasan can help
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Photo 7. Bittercress (Cardamine hirsute).
prevent the establishment of the weed.
Broadleaf weeds are not sensitive to grass herbicides. They can be selectively controlled in many turf settings with herbicides that do not kill the grass. Mechanical control is often another effective way to help manage broad-leaved weeds. The growing point on annual broadleaf weeds is typically higher on the weed where it is easier to reach than with a grass (where it is often located very low). If annual broadleaves are cut below the two cotyledons that emerge from the seed, the plant will die. As long as this is done before seed is set, it is a very effective means of control. Broad-leaved perennials are more difficult to control, as they can spread through stem pieces, rhizomes or stolons in addition to seeds. Dandelion (Taraxacum officinale)
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(Photo 3) is a perennial that has a deep taproot that can make management difficult because it will send up new shoots if the crown of the plant is cut. It also spreads readily by seed that is blown on the wind. Repeated digging can help control this plant if it establishes. Gallery is an effective pre-emergent, and 2,4-D post-emergent herbicides help manage this weed, but because it is so common and so easily spread by seed, management will be a yearly chore.
Horsenettle (Solanum carolinense) is an erect perennial weed most commonly found in dry sites. It spreads through seeds and rhizomes, so it is best to prevent this weed from establishing and to avoid
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cutting the rhizomes, which encourages spread. The plant is very spiny, which makes hand pulling painful, but horsenettle doesn’t tolerate mowing. If mowing does not provide satisfactory control, application of glyphosate can be used to provide additional control of the rhizomes.
Prickly lettuce (Lactuca serriola) is a winter or summer annual, or a biennial. The broad leaves and stems will leak a milky, sticky sap if cut, and there are sharp prickles on the back of leaf mid-rib. It is troublesome because a single plant can produce many wind-blown seeds that remain dormant for years in the soil. Cultivation and burndown post-emergent herbicides like Diquat are effective in managing this weed. Purple deadnettle (Lamium purpureum) and henbit (Lamium amplexicaule) are two winter annuals that are often confused with each other because they both are in the mint family, have square stems and similar flowers, and grow at the same time in the same areas. Purple deadnettle leaves (Photo 4) are triangular, and the leaves are clustered at the end of the stem, and they are usually distinctly purple at the top of the plant. Henbit leaves are whorled around the stem and are deeply lobed. A late-summer application of Gallery, a pre-emergent herbicide, is effective at killing these weeds but needs to be applied before the seeds germinate. Ground ivy (Glechoma hederacea), is a perennial that is can be confused with
cover story l continued
henbit. Ground ivy creeps along the ground, though, and it roots at the nodes, whereas henbit doesn’t. Gallery will not control established ground ivy, and other management methods will need to be use.
Chickweed can refer to several different weeds that all look similar. Three are in the Ceratstium genus: C. vulgarum (also called mouseear), C. viscosum (also called sticky chickweed) and C. arvense (also called field chickweed). Common chickweed (Stellaria media) (Photo 5) is in a different genus but looks very similar to the other three. Mouseear (Photo 6) is a perennial and not controlled by preemergents except at the initial establishment, whereas the other three are annuals controlled by pre-emergent herbicides. Mouseear is easier to distinguish from the others because the leaves are very hairy. Morning glory (Ipomoea sp.) is an easy weed to recognize as it has the same trumpet-shaped flower as the ornamental. It is a diverse genus, but most morning glories in Kentucky are annuals, with
simple leaves. These are difficult weeds to control with herbicides, as they are resistant to pre-emergents and even most post-emergent herbicides after they develop more than four true leaves. A simple, but labor-intensive, method of controlling them is by cutting them below the cotyledons with a string trimmer. Annual morning glories have no dormant buds below the cotyledons and so cannot regrow if cut there. If they are cut above the cotyledons, they will readily regrow from dormant buds in the leaf axils. They are also prolific seed producers, so it is important to manage them before they set seed.
Plantain (Plantago sp.) is a common turf
weed that can be difficult to control. The dark green leaves growing in a rosette, the erect seed heads and parallel veins in the leaves make these easy to spot and recognize. Control is more difficult as these are perennials, and the herbicides often only suppress the weed rather than kill it. Mulching where appropriate can be effective, as can digging.
Bittercress (Cardamine hirsute) (Photo 7)
is a common winter annual also commonly called snapweed because of the habit of the seed pods to snap open when dry scattering seeds over a large area. It is particularly a problem in container production where the plants are close together. Bittercress is not a large weed; usually, it is a rosette about 4" to 6" across and less than 12" high, topped by white flowers. It is easy to pull up as long as the seedpods are not mature. Snapshot is a pre-emergent that can be used in certain situations as well.
Summary While many other weeds could be discussed, these are some of the ones that have been reported as being most common and troublesome. Remember the key points: sanitation, correct identification and an integrated management strategy. If you are having trouble, contact your County Cooperative Extension Agent for assistance. 2
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Feature story
Plant Disease Diagnosis:
Making the Most of Your Resources By Julie Beale, University of Kentucky Plant Disease Diagnostician
W
ith the growing season just beginning, many professionals in the landscape, nursery and turf industries will be facing the challenges of field diagnosis. “Where do I even start?” is a common complaint for the new and seasoned professional alike. Here are a few reminders on conducting on-site diagnoses and the resources available to help. Diagnosing plant problems in a systematic fashion begins with knowledge of the normal appearance of a plant and continues with careful examination of the symptoms present. Aboveground symptoms are often related to belowground issues. For example, leaf scorch often indicates a problem in the roots or vascular transport system of a plant. Beyond a single symptomatic plant, other nearby plants may provide diagnostic clues. Do other plants also show similar symptoms? Are all plants of one type affected? Or are all plants — even those of different types — affected similarly? Did symptoms appear suddenly or progress over time? These patterns may help in determining whether the cause of symptoms is more likely to be a biological agent, such as a disease-causing pathogen or insect pest, or an abiotic factor, such as an environmental or cultural problem. The diagnostic process takes practice, practice, practice! There are many helpful resources related to plant-problem diagnosis, including print and online reference
materials. Also, a number of apps are available to walk the user through a step-by-step diagnosis of a given crop. The most appropriate references are those specific to the geographical/climatic region of the landscape in question. They should be produced by reputable publishers. Vast amounts of anecdotal accounts are online, but these are typically inappropriate for professional use. Sometimes, even the most experienced landscaper or nursery worker may still be “stumped” by a plant problem and require additional assistance. In Kentucky, landscape and nursery professionals, as well as non-professional clients, have access to the University of Kentucky Cooperative Extension Service and, via the Extension
Photo 1. The shrubs in this planting are in different stages of decline. Samples taken from plants in early and later stages of decline will be more useful than samples taken from the dead plant only. (Photo: J. Beale)
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Photo 2. Root samples may be more difficult to collect from larger, woody plants, but they are often key in confirming a diagnosis. If root samples cannot be collected, branch samples plus photos of the affected tree may help with a tentative diagnosis. (Photo: J. Hartman)
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Photo Photo 3. Packaging plants to protect the leaves from soil contamination ensures a useable sample. (Photo: J. Beale)
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Nurs ery Views • Spri ng 2017
Photo 4. This rotting pumpkin was packaged carelessly; the white material in the center is the paper form with the grower’s contact information, which was illegible. Although landscape samples tend to be less messy, careless packaging may delay the diagnostic process. (Photo: J. Beale)
Service, the UK Plant Disease Diagnostic Laboratory (PDDL). Plant samples are submitted for diagnosis to the local county Extension Office. Samples should be representative of the problem or problems in the site and account for the range of symptoms present (Photo 1). The best sample contains all the relevant plant parts whenever possible, since symptoms on one part may reflect diseases on another part of the plant. In
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Photos 5 and 6. Photos of the root flare and the whole tree with its surroundings provide information that a branch or foliar sample does not. These will help the diagnostician see the “big picture.” (Photo: J. Beale)
particular, since root diseases and injuries are often the real cause of foliar symptoms, whole plant samples are best. Although collecting whole plants may not always be feasible, sections of roots and branches of large, woody plants will be adequate in many cases (Photo 2). If a margin between healthy and damaged tissues is visible, this is a good place to sample. Occasionally, multiple types of symptoms are present in one location or even on a single plant. Careful
observations of plants in the site reduce the chances that samples under- or over-emphasize one type of symptom and miss the “big picture.” Once a sample has been collected, getting it to the county Extension Office or to the PDDL in good condition is a must — and can be challenging. Whether samples are driven to the office or shipped in the mail, one important point in handling samples is keeping soil and moisture away from foliage while leaving the soil
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Nur sery Views • Spr ing 2017
attached to roots. Soil microbes can quickly decay succulent leaf tissues, making diagnosis nearly impossible. Washing soil off the roots, however, may dislodge fragile fungal structures that lab personnel use to identify a disease. Carefully wrapping the root ball with soil in a plastic bag, and then gently tying the bag to prevent soil contamination of foliage, is a good way to stabilize plants for transport (Photo 3). Leave the foliage unwrapped or only loosely wrapped but lightly braced with dry, crumpled newspaper or other packing materials to protect it during moving. Detailed sampling recommendations are provided in the following UK Extension factsheet: PPFS-GEN-9, available on the UK Plant Pathology Department website. If multiple subsamples are submitted — for example, plants from different areas of a landscape or lawn — label these accordingly to prevent confusion. Diagnostic forms requesting information about the site, timing of symptoms and location/pattern of symptomatic plants, irrigation, maintenance and chemical application history are available at county Extension offices and are required when samples are forwarded to the PDDL. If plants must be shipped, forms should be sealed in a plastic bag for safe transit (Photo 4). Deliver or mail samples as quickly after collection as possible. Diseased plants can change rapidly, which affects the diagnosis. Photographs are often extremely helpful when they accompany a diagnostic sample. The types of photos that are most helpful are those that depict what the diagnostician cannot see, such as a view of a whole tree, the pattern of affected plants in a landscape and landscape features nearby that might impact a plant (Photos 5 and 6). Close-up photos are less useful since the diagnostician will have tools for very close examination once the physical sample is received. Photos should always be in focus. It takes time and practice to hone diagnostic skills. The diagnostic process is simply that: a process. Choosing and using available resources wisely is an important part of that process for anyone facing challenging plant problems. 2
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Thanks to Our Generous sponsors!
Nurture your Team & Bloom your Business!
January 25–26, 2017 • Ramada Plaza Louisville Hotel and Conference Center • Louisville, KY
PLATINUM SPONSORS
Ammon Wholesale Nursery (Platinum Sponsorship in Memory of Richard “Dick” Ammon) Burlington, KY Etter Lane Gardens • Georgetown, KY McHutchison, LLC • Louisville, KY Monrovia Growers • Dayton, OR
GOLD SPONSORS Carl Ray Landscape Nursery • Fischerville, KY Signature Landscapes • Nicholasville, KY Valley Hill Nurseries • Springfield, KY
Left to right: Kim Fritz (KNLA President), Cora Martin (Director), Mike Mueller (Vice President) and Todd Ryan (former Past President).
SILVER SPONSORS Barky Beaver Mulch & Soil • Moss, TN Kentucky Artisan Distillery • Crestwood, KY
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News About Next Year’s EXCITING EVENT!
The Kentucky Nursery and Landscape Association is dedicated to offering continuing education, networking events and certification programs that facilitate professional growth and elevate our industry’s standards. KNLA wants to provide you with the best opportunities that will help you and your company succeed. After careful consideration, KNLA is excited to announce that we will welcome our members to the 2018 Midwest Green Industry Experience (MGIX) in Columbus, OH, in lieu of holding a 2018 Spring Training and Showplace. The Midwest Green Industry Experience began in 2017 as a refreshed and redefined version of the Ohio Nursery and Landscape Association’s annual conference. Its mission: Welcome all who play a role in the green industry, in Ohio, Kentucky, Indiana and across the Midwest. The 2017 convention welcomed nearly 5,000 attendees for three days of education, networking events and a tradeshow experience that featured more than 250 exhibitors. MGIX 2018 takes place January 15–17 at the Greater Columbus Convention Center, and KNLA members receive discounted pricing on registration and exhibit space. The conference includes 90+ education sessions and will offer credits from a wide array of credentialing providers, including Kentucky Department of Agriculture Continuing Education Units (CEUs). A large exhibit hall features a demonstration stage and an arborist training center. Plans are underway for several evening events and family-friendly programs that invite you to bring your whole family to enjoy a long weekend in Ohio’s capital city. KNLA couldn’t be more excited about this partnership. We look forward to collaborating with ONLA to ensure that members of both associations receive an unmatched educational offering and networking experience. We will continue to keep you updated as more details are planned. In the meantime, we invite you to learn more about the conference at www.mgix18.com, and contact us at knla.org@gmail.com with any questions.
Thanks to Our exhibitors! Abrams Nursery • Crestwood, KY
KY Dept. of Agriculture • Frankfort, KY
Smith Creek • Borden, IN
Ammon Wholesale Nursery • Burlington, KY
Kentucky Nursery and Landscape Association • Frankfort, KY
Snow Hill Nursery, Inc. • Shelbyville, KY
Anderson Mulch & Soil, LLC • Tompkinsville, KY
Klyn Nurseries • Perry, OH
Arbre Technologies • Milwaukee, WI Barky Beaver Mulch & Soil • Moss, TN Caudill Seed, Inc. • Louisville, KY
Louisville Tractor • Louisville, KY Millcreek Gardens LLC • Ostrander, OH ML Irrigation • Midway, KY Natorp Wholesale Nursery • Mason, OH
Stockdale Tree Farm, LLC • Hazel, KY Strain and Son’s Nursery • Athens, AL United Label • Cleveland, OH University of Kentucky Nursery Crops Program • Lexington, KY University of Kentucky State Entomologist • Lexington, KY
Construction Machinery Co. • Louisville, TN
Premium Horticultural Supply Co. • Louisville, KY
Dayton Bag & Burlap • Dayton, OH Greenleaf Nursery Co., Inc. • Park Hill, OK
Richey Nursery Company • Spring Lake, MI Riverfarm Nursery • Goshen, KY
Village Green Wholesale Nursery • Springfield, KY
Hans Nelson & Sons Nursery • Boring, OR
Rubley’s Nursery • McMinnville, TN
Wilkerson Financial • Frankfort, KY
Highland Moor • Midway, KY
SiteOne Landscape Supply • Lexington, KY
Zeppa’s • Prospect, KY
Valley Hill Nurseries • Springfield, KY Nur sery Views • Spr ing 2017
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advertisers index
Ammon Wholesale Nursery, Inc............ 9
Jelitto Perennial Seeds......................... 13
anderson mulch & soil, LLC.......................5
Low Falls Wholesale Nursery............ 19
Barky beaver mulch & Soil mix, Inc....... 19
McHutchison Horticultural.................. 7
bobcat enterprises, inc.............Inside Front Cover
Millcreek Gardens, LLC.......................... 22
www.ammonplants.com www.ralumber.com
www.barkybeaver.com
www.bobcat-ent.com
Boshancee nursery, inc........................... 7
www.boshanceensy.com
Braun horticulture................................ 14
www.mchutchison.com
www.millcreekplants.com
Motz and son Nursery.............................. 7 Richey Nursery Company, LLC.............. 19
www.richeynursery.com
SAmara farms..............................Back Cover
Buckeye resources, inc........................... 3
Smith Seed Services................................. 22
Center Hill Nursery................................ 22
Thomas Nursery........................................ 22
Fairview Evergreen Nurseries............ 15
tree equipment design inc...................... 7
Hortica......................................................... 16
Wellmaster Carts......... Inside Back Cover
www.centerhillnurseries.com www.fairviewevergreen.com
www.hortica-insurance.com
Digital
Marketplace Scan the QR code: Download a QR reader to your phone and scan the code to learn more about these companies.
Nurs ery Views • Spri ng 2017
www.lowfallsnursery.com
www.braungroup.com
www.buckeyeresources.com
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www.jelitto.com
www.smithseed.com
www.thomasnurserytrees.com www.treeequip.com www.wellmaster.ca