Lawns, Gardens & Trees

Accessibility


Lawns, Gardens & Trees

| Share

EAB and insecticides

EAB, emamectin benzoate, imidacloprid, dinotefuran, TreeAge. Insecticides are not recommended at this time, but this information may be useful to those educators who are, or will be, dealing with this issue.

Since EAB was discovered in the U.S., researchers have focused much of their efforts towards finding effective control treatments.  Experimental results are variable – some treatments are highly effective, but others are less so.  The latest research results can be found in the 2nd edition of ‘Insecticide Options for Protecting Ash Trees from Emerald Ash Borer’, which came out in 2014: http://www.emeraldashborer.info/files/multistate_EAB_Insecticide_Fact_Sheet.pdf.  A summary is listed below. Note that new research results are coming out all the time, so recommendations may change is the future. As always, follow all pesticide label directions carefully.  

Updated version, June 2014

Spray-type treatments with traditional broad-spectrum insecticides have been the least effective at controlling EAB. Quite simply, EAB adults can be active through most of the summer, and the insecticides didn’t last long enough to provide enough control. Additionally, obtaining a thorough spray coverage is very difficult, especially with larger trees.

Systemic chemicals, those that move within the tree, have proven more effective. Those with the active ingredients ‘imidacloprid’ and ‘dinotefuran’ have been researched extensively and are available in multiple formulations. Some formulations can be applied as a soil drench, a soil injection, a granular product applied to the soil surface, a bark-penetrating spray, or a stem injection (professionals only). These chemicals move through the tree to the tissues that EAB feed on. Control is not 100%, but these pesticides do a very good job of reducing the number of EAB larvae feeding beneath the bark.

The most effective insecticide treatment by far has been stem injections with the active ingredient ‘emamectin benzoate’. Test results have shown that this product provides better than 99% control of EAB larvae – and that level of protection lasts for at least two years. Many communities in the Midwest have found that a combination of insecticide treatments, along with timely removal of low-value trees, is incredibly useful in managing the ash trees in their urban forests.

Additional information about EAB is available from the ND Department of Agriculture at: http://www.nd.gov/ndda/pest/emerald-ash-borer-eab.  For more information about tree pests such as Dutch elm disease, gypsy moth, and others, please visit the ND Invasives website at: http://www.ndinvasives.org/.  

| Share

EAB - Let's diversify our tree plantings

In the wake of Dutch elm disease, green ash was the most-common replacement tree. Let's not repeat that mistake with emerald ash borer (EAB). Many hardy species and varieties will grow in North Dakota. Visit the ND Tree Selector at: http://www.ag.ndsu.edu/tree-selector/.

Many years ago, American elm was the most common tree species planted in urban areas of the Great Plains. In some areas, it was the only tree species. Then, Dutch elm disease came and wiped out the tree canopy. People searched for a new species to replace the elms, and they came up with green ash – a tall, fast-growing tree that is tough enough to handle the urban environment. Again, people relied on a single tree species and green ash was overplanted. With the approach of emerald ash borer, the importance of diversity in tree plantings cannot be overstated.

Many species of tall deciduous trees are available for conservation plantings as well as in urban areas. (Some, such as cottonwood or boxelder are probably better suited to conservation plantings.) The ND Tree Selector (http://www.ag.ndsu.edu/tree-selector/) is an online tool that helps users choose tree and shrub species based on a variety of characteristics. Are you looking for something that is fast growing? Or a tree that is long-lived? Perhaps a species with pretty flowers?  The ND Tree Selector can help you find species to consider for your next planting.

ND Tree Selector

And don’t forget to visit with your local professionals – city foresters, nursery owners and many others who have been planting trees for years can make recommendations about which species will do well – and those that won’t! 

Additional information about EAB is available from the ND Department of Agriculture at: http://www.nd.gov/ndda/pest/emerald-ash-borer-eab.  For more information about tree pests such as Dutch elm disease, gypsy moth, and others, please visit the ND Invasives website at: http://www.ndinvasives.org/.  

| Share

EAB - Financial impact and the value of trees

Emerald ash borer (EAB) will have a very large impact on North Dakota. Costs include - removals, replacements, treatments, and the lost amenities provided by millions of shade trees and thousands of miles of shelterbelts.

The financial impact of EAB is incredible. Direct costs include tree removals (don’t forget stump grinding) and planting replacement trees. For those people who want to save specific ash trees, stem injections with the chemical ‘emamectin benzoate’ have been extremely effective – but they’re definitely not free. Indirect costs are also large – losing a prime shade tree can result in an increase in electric bills by more than 25%. That loss of shade has also resulted in an increase in water bills, as exposed lawns have needed additional irrigation. Property values have decreased in some communities as the overall tree cover has declined. One study even found an increase in heart and respiratory diseases in those areas that have been hardest-hit by EAB.

A structurally unsound ash tree in Fargo, that should be removed.  Given its location, it will be expensive to remove.

Many North Dakota communities’ urban forests are comprised of more than 50% ash trees. In one study of four North Dakota small towns, the cost of removal-and-replacement was estimated from $22,000 to more than $163,000; that study was completed 5 years ago and costs increase every year. Insecticide injections provide an alternative to removals-and-replacements, and may be a cost-effective option for managing the urban forest. The EAB Cost Calculator from Purdue University allows users to compare the costs of different management alternatives: http://extension.entm.purdue.edu/treecomputer/index.php.

Technical and financial assistance for developing community-level management plans is available from the ND Forest Service. Contact Gerri Makay at (701) 652-2951 or Gerri.Makay@ndsu.edu for more information.

Additional information about EAB is available from the ND Department of Agriculture at: http://www.nd.gov/ndda/pest/emerald-ash-borer-eab.  For more information about tree pests such as Dutch elm disease, gypsy moth, and others, please visit the ND Invasives website at: http://www.ndinvasives.org/.  

 

Technical and financial assistance for developing community-level management plans is available from the ND Forest Service. Contact Gerri Makay at 701-652-2951 or gerri.makay@ndsu.edu for more information. 

| Share

EAB and firewood

EAB (Emerald Ash Borer) is moved long distances in firewood and other materials. We urge people to "Burn it where you buy it" and "Don't move firewood." It's a difficult sell, because regulations are sometimes confusing and inconsistent.

Campground managers, foresters and many others are encouraging their clients "Don't move firewood" this summer and throughout the year.  Movement of infested firewood has been one of the main methods of long-distance dispersal of emerald ash borer (EAB).  The legal regulations regarding firewood movement can be rather confusing, with some examples listed below.  In order to avoid the hassle, simply "Burn it where you buy it."

  • A federal quarantine is in place around all of the known EAB-infested areas of the U.S. Moving firewood and other ash products out of the quarantine area is illegal unless very specific, highly detailed rules are followed.
  • ND Forest Service - prohibits out-of-state firewood at their campgrounds, but they will provide a free bundle of firewood for each paid campsite.  Additional firewood is available for $3.00 per bundle.
  • US Army Corps of Engineers - at campgrounds in North Dakota, firewood must originate within 100 miles of the campground, unless it has been officially certified as pest-free.
  • MN Department of Natural Resources - in Minnesota, "it is against the law to bring unapproved firewood into any state park, state forest or day-use area." In these locations, firewood must be purchased from a DNR approved firewood vendor. For more information, go to: http://www.dnr.state.mn.us/firewood/index.html.

Firewood Alert - flier developed by ND Forest Service.  Urging all campers and others, "Don't move firewood", and "Burn it where you buy it."

| Share

Emerald Ash Borer - Signs and Symptoms

As part of EAB Awareness Week, we need to understand what to look for when determining whether or not a tree has been attacked by Emerald Ash Borer.

The signs and symptoms of EAB are varied: dieback of the branches in the crown, new branches sprouting from the stem, D-shaped exit holes from the adult insects.  And eah one of these can be caused by something other than EAB.  Correct diagnosis and confirmation of the true cause of problems in ash trees is difficult but it’s critically important – treating for the wrong problem is a waste of time and money.  At the other extreme, missing an opportunity to treat a problem is equally as bad.  The first step in determining if EAB is killing a tree is to confirm that it is actually an ash – http://www.ag.ndsu.edu/pubs/plantsci/trees/f1633.pdf.  For more information on the actual signs and symptoms of EAB, go to: http://www.ag.ndsu.edu/pubs/plantsci/pests/e1634.pdf.

EAB larva and gallery.

EAB is tricky to diagnose for those who are not been trained.  If you think that your ash tree has Emerald ash borer, please contact one of the following people.

Aaron Bergdahl, ND Forest Service – aaron.d.bergdahl@ndsu.edu, 701-231-5138

Joe Zeleznik, NDSU Extension Service – joseph.zeleznik@ndsu.edu, 701-231-8143

Charles Elhard, ND Department of Agriculture – celhard@nd.gov, 701-239-7295

Additional information about EAB is available from the ND Department of Agriculture at: http://www.nd.gov/ndda/pest/emerald-ash-borer-eab.  For more information about tree pests such as Dutch elm disease, gypsy moth, and others, please visit the ND Invasives website at: http://www.ndinvasives.org/. 

 

| Share

Emerald Ash Borer - Overview and Background

EAB Awareness Week, May 17-23, 2015. Covering a variety of topics, including signs/symptoms, 'Don't Move Firewood' campaign, the value of North Dakota's ash trees, replacement trees, and potential treatments.

Graphic depicting emerald ash borer (EAB) with a circle-slash.

Emerald ash borer (EAB) was introduced to the Detroit, Michigan, area in the mid-1990s.  Since then, it has spread outward in an ever-expanding infestation.  EAB is not a strong flier, so long-distance travel has been through people – movement of infested firewood, wood products and nursery stock.  One big lesson that we’ve learned is ‘Don’t Move Firewood’, or ‘Burn it where you buy it’: http://www.dontmovefirewood.org/.  For the latest map showing the current location of EAB, go to: http://www.emeraldashborer.info/files/MultiState_EABpos.pdf. 

EAB attacks all ash (genus Fraxinus) species that are native to the U.S.  [It does not attack mountain-ash trees, as they are not true ash species, but instead are in the genus Sorbus.]  EAB has a major impact on those communities with a heavy reliance on ash.   In North Dakota, many communities’ urban forests are comprised of more than 50% green ash; in some towns that figure approaches 80%.  The importance of diversification can’t be stressed enough.  For more information on trees that are adapted to North Dakota, see the ND Tree Selector at: http://www.ag.ndsu.edu/tree-selector/. 

Additional information about EAB is available from the ND Department of Agriculture at: http://www.nd.gov/ndda/pest/emerald-ash-borer-eab.  For more information about tree pests such as Dutch elm disease, gypsy moth, and others, please visit the ND Invasives website at: http://www.ndinvasives.org/. 

| Share

Spring Fever Gardening Workshops Set

Spring Fever Garden ForumsIf you want to learn about selecting trees or growing a productive garden, the North Dakota State University Extension Service's Spring Fever Garden Forums can help.

NDSU Extension is offering the series of workshops for gardeners across the state Monday and Tuesday nights, March 23, 24, 30 and 31, from 6:30 to 8:30 p.m. Central.

A team of 12 university experts will present information on timely topics in gardening and landscaping and then answer your questions.

Topics also include landscaping with flowers, pruning shrubs, attracting pollinators, growing fruits and herbs, and protecting plants from diseases.

The presentations will be made to a live audience in Fargo and delivered to more than 40 Extension sites across the state. Gardeners may attend at these sites or go online and participate in the live presentations on their home computer.

"More than 1,000 gardeners will participate in this mega-event," states Tom Kalb, Extension horticulturist. "It is a great opportunity to learn of gardening trends and see the latest research from NDSU."

The workshops are free of charge. For a full list of presentations and to register, go to http://www.ag.ndsu.edu/springfever.

Written by Tom Kalb, Extension Horticulturist. Edited by Ellen Crawford, Information Specialist.

| Share

Gift ideas for gardeners

These gifts will bring happiness to your friends and family.

'Appleblossom' amaryllisThe holidays are here and so are the busiest shopping days of the year! Gardening is America’s #1 hobby and you can bring happiness to others by giving gardening presents. 

Amaryllis is a great holiday gift. It is showy and one of the easiest plants to grow. A quality bulb company can offer extra large bulbs that will bloom this year and in future years too. Always remember: the bigger the bulb, the better.

The following is a brief description of more gift ideas:

Lightweight gardening hoses are getting popular. Good pruning tools are always appreciated. A pocket knife is a handy gift. Solar-powered gardening pots are popular—they glow at night!

A new shovel, spading fork or hoe will be appreciated by a true gardener. A garden cart can help your friend move plants and tools around their yard.

Nitrile garden gloves are very popular. Hand scrubbing lotions will clean and moisturize our hands (the most important gardening tools). 

We all need to eat more veggies. A juicing machine can help us to get all the servings we need for a healthy diet. A dehydrator can convert our garden produce into nutritious snacks.

Thermometers, soil thermometers and rain gauges provide valuable information to a gardener.

Gnomes and other garden statuary are risky gifts, but sometimes these gifts bring the biggest smiles!

When all else fails, a gift certificate to a local garden center or a gardening catalog will put a smile on your friend’s face.

Happy holidays!

Written by Tom Kalb, Extension Horticulturist, North Dakota State University. This article is an excerpt of a story published in the NDSU Yard & Garden Report, November 15, 2014. The photo was made available under a Creative Commons license specified by the photographer: Liz West.

| Share

Sparkling jewels

Crabapple fruits add sparkling color to the winter landscape.

Red crabapple fruit in winterCrabapple trees have dropped their leaves and most have dropped their fruit, too. This litter creates a mess. That’s unfortunate. These fruitless trees will look unremarkable all winter long. That’s really unfortunate.

Why not select a variety with persistent fruit? Some crabs hold onto their fruits through much of the winter, adding sparkles of red and gold in the landscape. These fruits will also attract songbirds, adding another dimension of life and color to your home surroundings.

Red Jewel™ is renowned for its display of bright red fruits during winter. ‘Donald Wyman’, Sugar Tyme®, ’Prairfire’ and Sargent are other outstanding red-fruited types.

If you are looking for something different, ‘Snowdrift’ and ‘Professor Sprenger’ have orange fruits and the yellow fruits of Harvest Gold® are absolutely fascinating.

The next time you look for a crab, don’t focus on its spring flowers—these last for a couple weeks. Instead, consider how the tree looks during winter—this lasts for five months. Consider a crabapple with persistent fruit.

Written by Tom Kalb, Extension Horticulturist, North Dakota State University. Published in the NDSU Yard & Garden Report, November 15, 2014. The photo was made available under a Creative Commons license specified by the photographer: Leah Grunzke.

| Share

Know your manure

Know where your manure comes from and avoid contaminating your garden with herbicide.

Horse with manure in pastureMany gardeners add manure to their gardens in fall. Please be sure you know where your manure comes from. Some farmers spray their pastures with pyridine herbicides to control broadleaf weeds. These herbicides include Crossbow, Curtail, Forefront, Grazon, Milestone, Redeem and Surmount.

Manure from livestock feeding on pyridine-treated hay or pasture grass should not be used in gardens. The chemical passes through the animal without decomposing. When gardeners use this manure, they are literally adding a persistent herbicide to their soil. The hearts and hopes of many of the best gardeners in our state have been broken. 

Tomatoes, potatoes, peas and beans are extremely sensitive. Affected plants will stretch and curl, similar to damage caused by dandelion killers that drift onto plants. Pyridine can persist in manure for a few years—be very careful!

Written by Tom Kalb, Extension Horticulturist, North Dakota State University. Published in the NDSU Yard & Garden Report, October 15, 2014. The photo was made available under a Creative Commons license specified by the photographer: Malene Thyssen.

Creative Commons License
Feel free to use and share this content, but please do so under the conditions of our Creative Commons license and our Rules for Use. Thanks.