Their names are similar and they’re from the same region of the world, so I can see why some people are still confused about Asian lady beetles and Japanese beetles. But when it comes down to it, there’s really no comparison. The bug pictured here – the reddish/orange lady beetle, is a beneficial insect. It feeds on aphids and other plant pests and doesn’t destroy anything, though I realize some people resent their intrusion in homes in the fall. On the other hand, the copper-colored Japanese beetle, a recent foreign invader in Iowa, is known to devour at least 300 plants, including hollyhocks, roses, raspberries, linden trees and grapes. If you see your leaves turning to lace, the likely culprit is the Japanese beetle. Japanese beetles have no known predators here, other than me. So feel free to get rid of as many as you can. As mentioned previously, the most environmentally friendly method is to knock them into a bucket of soapy water when they’re sluggish – early evening seems to be the best time. If you have other suggestions – maybe from our East Coast readers and others who have learned to cope with Japanese beetles – please add your comments below.
Posts tagged beetles
I spotted the first Japanese beetle of the season yesterday on my raspberry bushes. I went to check one of my rose bushes and sure enough, there was another one, sucking the life out of a beautiful pink bud. Unfortunately, both got away.
The beauty of these copper-colored beetles belies the devastation they wreak. Adult Japanese beetles feed on more than 300 types of plants – turning leaves into lacy skeletons. As larva, the white c-shaped grubs feed on turf grass roots.
I’ve heard some people have luck with the Japanese beetle traps that can be found at garden centers. Others say the traps just lure more beetles into your yard. When I see just a couple of the bugs, I use the squish method, but as they become more numerous, I’ll try to control their numbers with soapy water.
Take a small bucket with water and dish detergent – any kind will probably work – and knock the beetles off the plants into the bucket. The beetles are more active at certain times of day and will fly off. Othertimes, they do a drop and roll, which is the best way to get them to fall into the bucket. Early evening seems to be the time when they are more sluggish and easier to catch that way. Obviously, if you are growing crops that the beetles are attacking, such as grapes (another favorite,) you’re going to need a different method of control. They also favor certain trees, but supposedly they don’t kill the trees as do pests like the emerald ash borer. I also wonder what they will ultimately do to the monarch butterfly population, as Japanese beetles devastate the monarch’s food source, milkweed.
Since they make my top 10 bad bugs list, the Japanese beetle and different control methods can be found in several posts on this blog. Just use the search box at the right to find more from city arborist Daniel Gibbons, master gardeners and others on this foreign invader.
Linn County Master Gardener, Claire Smith, wrote the following: The driver of the car at the stop light next to me looked rather aghast when I broke into a hearty laugh this morning. I guess some radio and TV facts are just meant to be light hearted even though reported in a most serious manner, for example, the obnoxious little black flies that are so prevalent this spring are called buffalo gnats. Do you know why? Because they have a hump in their back. With no disrespect intended to those folks who study insects, that “need-to-know” fact really struck my funny bone.
Not so funny is in the onslaught of beetles again this year. Just a reminder, do not spray edible plants to rid the beetles. Traps seem fairly effective. The traps do attract the little critters in addition to killing them so it is suggested you locate traps at the ends of your property.
The ugly tunnels in your lawn are probably mole trails. Another little known fact is that moles eat more than their own weight in worms daily. Worms are good for the soil. They constantly aerate the earth. Keep the worms; eradicate the moles. The most practical method of eviction is a scissor or harpoon type trap. Locate the active tunnel by tamping down all of the tunnels. Place the trap in the one the mole reopens.
And then there are the garden invaders, the ground hogs, rabbits and raccoons. Probably the best offense against them is a good fence. Hardware cloth or wire mesh should be at least 1½ to 2 ft. tall supported with wood or metal stakes. Bury the fence into the ground a bit or secure it down with landscape pins. Repellents are somewhat effective, but more costly as they need to be reapplied after each heavy rain. You could consider live traps, but the last time we tried live traps, an opossum was smarter than we were. We did capture two cats, though.
And, finally, Oh! Deer! It is best to discourage deer before they become accustomed to the delicacies in your garden or yard. The most reliable deer prevention maintenance is a fence. However, a deer proof fence will be at least eight feet tall which can be a costly venture, be aesthetically unattractive, and possible prohibited by local building codes. Repellents and scare tactics are ineffective as deer ignore them. Try temporary fences around new plants and special plants. Deer may force you to choose plants that are less tasty to them, have an unusual texture, or a strong aroma. Call your local extension office (in Linn County 447-0647) for a list of deer resistant plants. Perhaps impractical in some cases, a good dog will be as efficient as anything else you might try.
The following is by James Romer, Extension Horticulturist at Iowa State University:
This time of the year gives many gardeners an empty feeling. It is hard to keep warm and dry when temperatures dip below zero and it snows every other day. It is reminiscent of those classic song lyrics — “All the leaves are brown and the sky is gray … California dreamin’ ….” Anyway, this is a great time of the year to do some planning and pruning.
The late dormant period (February to early April) is an excellent time to prune deciduous trees. The absence of foliage at this time of year gives the home gardener a clear view of the tree and allows him/her to select and remove appropriate branches.
Proper pruning improves the appearance, maintains the health and prolongs the life of trees. Improper pruning destroys their natural beauty, weakens them and may lead to their premature death.
It is essential to make proper cuts when pruning trees. Do not make flush cuts. Flush cuts are cuts made as close as possible to the trunk or main branch. Flush cuts produce large wounds, destroy the tree’s natural mechanisms that promote healing and slow the “healing” process.
When pruning trees, make the final cut just beyond the branch collar and branch bark ridge. The branch collar is the swollen area at the base of the branch. The branch bark ridge is the dark, rough bark ridge that separates the branch from the main branch or trunk. Pruning just beyond the branch collar and branch bark ridge retains the tree’s natural defense mechanisms and promotes the healing process. When a branch is pruned properly, a slightly raised area remains on the trunk or main branch. However, do not leave stubs.
Do not apply wound dressings to pruning cuts. The application of wound dressings or paints doesn’t stop decay and may actually inhibit or delay the healing of wounds.
There is one exception with not applying paint to oak trees. Oak wilt is a fungal disease that is lethal to many oaks. Oak wilt infections occur most commonly in spring and early summer and are spread from infected trees to healthy trees by sap-feeding beetles. To reduce the risk of the spread of oak wilt, don’t prune oaks from April 1 to July 1. If oak trees must be pruned between April 1 and July 1, for example, to correct storm damage, immediately apply a latex paint to all cut surfaces to avoid attracting sap-feeding beetles to the wounds.
Use the three-cut procedure when cutting large branches to prevent extensive bark damage. Make the first cut about one to two feet from the main branch or trunk. Cut upward and go about halfway through the branch. Make the second cut a few inches beyond the first. Cut downward completely through the branch. Make the final cut just beyond the branch collar.
Some trees, such as maple, birch and elm, bleed heavily when pruned in late winter or early spring. However, the heavy bleeding doesn’t harm the trees. (The trees won’t bleed to death.) Eventually the flow of sap will slow and stop. Heavy bleeding of susceptible trees can be avoided by pruning in late June or early July.
The pruning of deciduous trees by the home gardener should be limited to small trees and the removal of smaller branches that can be reached from the ground in medium to large trees. Branches high up in large trees and those near utility lines should be left to professional arborists. Professional arborists should have the proper training and equipment to safely perform the job.
If that’s not enough to do, another enjoyable winter activity is to leaf through garden catalogs. Many contain colorful plant photographs. Some carry specific merchandise, such as seeds, perennials, roses or fruits. Others carry a wide variety of products.
Also, visit a bookstore or public library and browse through some of their gardening books. Excellent reference books for home gardeners include “Manual of Woody Landscape Plants” by Michael Dirr; “Continuous Bloom” by Pam Duthie; “Herbaceous Perennial Plants” by Allan Armitage, and many others.
Remember also that your Iowa State University Extension county office has numerous publications on gardening in Iowa. Most of these publications also are available from the ISU Extension Online Store at www.extension.iastate.edu/store.
So get busy planning, pruning and dreaming about plants for this spring.
Linn County Master Gardener, Susan Long, prepared the following Q & A’s that are frequently asked of Hortline volunteers in November.
Q: Can I plant potted mums in my garden now for blooms next year?
A: Even though potted garden mums may be deemed “hardy”, they don’t over-winter well in Iowa. The repeated freezing and thawing may heave the plants out of the ground causing damage or death. The best protection is to not cut back any of the plant and mulch heavily with clean straw, pine needles, or evergreen branches after several hard freezes (mid to late November). Leaves tend to mat down and don’t serve as adequate protection. Spring is a better time to plant mums as they have the summer to establish themselves.
Q: Is it OK to prune oak trees now?
A: Winter (December through February) is the best time to prune oak trees in Iowa. Pruning oak trees in winter greatly reduces the risk of an oak wilt infection. Oak wilt is a fungal disease that is lethal to many Oaks. It can be spread from infected trees to healthy trees by sap-feeding beetles. Oak wilt infections occur most commonly in spring and early summer. Pruning oak trees in winter greatly reduces the risk of an oak wilt infection as the beetles and fungal mats are not present at that time of the year.
Q: How do I get my Christmas cactus to bloom at Christmas?
A: Day length and temperature control the flowering of a Christmas cactus. Temperatures shouldn’t be above 70’ in the daytime with nighttime temperatures of 60-65’. Provide your plants with bright day light, not artificial light, until mid-October. Move the plant to an unused location after mid-October, giving your plant 14 to 16 hours of continuous darkness each day for at least 3 weeks. Keep the soil conditions dry, watering every 7-10 days. They don’t like to be moved, however, once buds set the plant can be moved to another location. Your plant should start to bloom at Christmas.
The following is from Linn County Master Gardener, Claire Smith:
Are you ready for the cold weather? It’s been just plain chilly the past few mornings! Does it make you think it’s time to get wood ready for your fireplace? Is there a better way to spend a snowy day than with hot chocolate, a great book and a toasty fire? But, beware of bugs! While the Box Elders and Beetles seemed not as prolific this summer, be careful you’re not transporting a host of other multi-legged critters along with your fire wood.
Firewood is best kept out of the weather. Store it in your garage, a storage shed, or at the least protected under a roof. Whether you have your firewood delivered or chop your own, it’s a good idea to keep the wood up off of the ground. Firewood holders with metal legs are wonderful as it is difficult for the insects to crawl up into the wood. Insects will often seek a moist area to reside, so if a metal holder is not probable, at least use wood pallets to get the wood off the ground allowing it to dry and preventing rotting.
To minimize the number of insects coming into your home, let the firewood you will use in one or two days set outside in the cold for one or two days prior to moving it inside as insects need a couple of days to warm up before becoming active Never, never use insecticide on your firewood. There is really little benefit to treating the wood, plus you create a potentially dangerous situation with vapors emitted into your living room.
Long horned beetles, metallic wood-boring beetles and bark beetles attack dead and dying trees. Pillbugs, centipedes, millipedes and ground beetles are the most common insects found in firewood. These insects are basically just a nuisance. None are harmful to you or pets so when you see an occasional insect emerge from the wood in your house simply remove it from the premises, then enjoy the ambiance you’ve created.
The watch continues for the notorious emerald ash borer, a pest that has devastated ash trees in at least seven states, including neighboring Illinois.
The emerald colored bugs appeared near Detroit six years ago and have been advancing toward Iowa.
Having seen photos of the emerald ash borer, I quickly reacted when I saw a pretty emerald bug outdoors earlier this summer.
Iowa State University has an awesome insect identification program that allows Iowans to e-mail a photograph of their bug and have it identified by entomologists.
I shot a photo of my bug next to a ruler to show its size and sent it to the site.
Good news: it wasn’t an emerald ash borer. Bad news: I had killed a sixspotted tiger beetle, a beneficial insect that extension entomologist Donald Lewis said is easily mistaken for an emerald ash borer.
Lewis tells me the beetles are predators that chase other insects across the ground in woodlands. They hunt food like a tiger.
Tiger beetles are ecologically beneficial. They are not a pest. The beetles do not bite, sting or carry disease. They do not feed on crops, trees or houses. They are remarkably fast and difficult to catch.
I’m bummed that I caught one, but glad it wasn’t an ash borer.
Lewis says the emerald ash borer is much smaller and narrower and does not have the long sharp jaws of a tiger beetle (predatory
For Iowans who have a bug they’d like identified, specimens can be submitted to the Iowa State University Plant and Insect Diagnostic Clinic for diagnosis at no charge.
You can e-mail a close-up digital image to email@example.com
Specimens can also be sent to the clinic.
Bugs should be dead when shipped and mailed in a bottle, box or padded envelope. Soft-bodied insects such as caterpillars, aphids and ants, and spiders, mites and ticks can be preserved in hand sanitizer gel. Hard insects such as moths, butterflies and beetles do not need to be preserved, but they should be restrained inside the container so they don’t bounce around during shipment (for example, secure a moth or butterfly inside a box with layers of dry paper toweling.)
Mail sample to:
Plant and Insect Diagnostic Clinic
327 Bessey Hall
Iowa State University
Ames, IA 50011-3140
Include information about where you live, where you found your insect, and how to get in touch with you.
For a photo of the emerald ash borer, go to: http://www.emeraldashborer.info/files/E2944.pdf