ISSUE 2 May 13, 1999ASIAN LONGHORNED BEETLE
Asian longhorned beetles (ALBs) " . . . would make Dutch elm disease look like small potatoes" according to U.S. Undersecretary of Commerce, David Aaron. No ALBs have been found in North Dakota, but established populations of this insect have been discovered in Illinois and New York state.
The Asian Longhorned Beetle (Anoplophora glabripennis) is a wood boring insect, known to attack and kill apparently healthy trees. This insect is native to Asia and is believed to move transcontinentally as a stowaway in wood pallets, crates, and dunnage. The first established populations of ALBs in North America were found in Brooklyn and Amityville, New York in 1996. After approximately 1,500 infested trees had been destroyed, ALBs appeared to be under control by December 1997. During the summer of 1998, ALBs were identified in three Chicago suburbs. Scientists believe that the beetles arrived at these locations sometime between 1991 and 1993. There is a real threat that ALBs may enter (or may have already entered) elsewhere in North America.
ALB adults are shiny, coal-black, 1" to 1 ¼" long beetles with white dots. They have black and white striped antennae, which are longer than their bodies. Larvae can reach nearly 2" in length and are difficult to distinguish from other wood-boring insects. ALBs leave approximately ½" wide circular exit holes.
In an APHIS (USDA Animal and Plant Health Inspection Service) press
release for October 1, 1998, the U.S. government showed that it was taking action in an
attempt to prevent future introductions of ALBs and other wood boring insects into the
United States. That release stated "effective Dec. 17, all shipments from China
containing solid wood packing material must be accompanied by official certification
stating that the solid wood packing material was treated with preservatives, heat treated,
or fumigated before leaving China." No beetles have been found in North Dakota to
date, but we should keep our eyes open
for the next few years to ensure that the insect is not present in our state. The northern limits where ALBs will become a pest in North America is not fully understood. Although we do not know whether this insect could survive North Dakota winters, some of its favored hosts include trees which are grown in our state. In Asia, boxelder (Acer negundo) and sugar maple (Acer saccharum) are planted as trap trees for ALBs to protect higher-valued hardwoods; therefore, these two species are expected to be at high risk. Maple, poplar (Populus), and willow (Salix) are primary hosts of ALBs in China, while plum (Prunus), pear (Pyrus), and elm (Ulmus) are occasionally infested in that country. Thus far, maple, birch (Betula), poplar, willow, and elm have served as hosts in the United States.
Regulations, inspections, surveys, and rapid response to infestations are required to keep this insect from becoming established across North America. When infested trees are found, they must be cut down, chipped, and burned to keep ALBs from moving onto other trees. Since ALBs can burrow deep into wood, insecticides are not believed to be effective in eradicating the borers from infested trees. Questions concerning the use of insecticides, development of synthetic attractants for ALBs, and other details about ALB biology must be researched to aid in preventing the establishment of this exotic insect in additional areas of North America.
During the summer of 1998, North Dakota State Entomologist, David Nelson, found larval tunnels consistent with those made by ALBs in wood pallets used to ship goods from China to a sporting goods store in North Dakota. ALBs are probably not present in the state, but to confirm that no ALBs are within North Dakota, letters were sent to City Foresters across the state with color picture identification cards supplied by APHIS. Anyone who finds an insect that they believe to be an ALB, is asked to contact the NDSU Extension Forester (701-231-8478), the North Dakota Department of Agriculture (701-239-7295), or the USDA Animal and Plant Health Inspection Service (701-250-4473) immediately. A rapid response to new infestations is critical in successfully eradicating ALBs before they become established.
WHEN IN SEPTEMBER, TRY TO REMEMBER THESE DAYS IN MAY.....
Not quite the right words to the well-known song, but close enough! Mark your calenders though, because these windy, rainy days that have been roaring across the region these last few weeks are definitely going to have an effect on tree fruit set. The wind, rain, and in some instances, the low temperatures, will certainly inhibit the activity of the pollinating insects. Expect the apples, plums, pears, and cherries to have sparse fruiting.
The spring weather weve experienced thus far is good reason for not getting into the apple, plum, or cherry orchard business in North Dakota. The month of April was warm enough to tease the flowering trees and shrubs out of dormancy, only to run into a windy, cold, and rainy wall in early May! As a hobby, this merely causes an annoyance or inconvenience; as a means of making a living, it is a disaster!
Other Concerns For The Month Of May:
Black knot has become so common on cherry trees that I have difficulty making a recommendation for this species any longer in most of North Dakota. In the 14 years that I have lived here, it has gone from a rare, somewhat obscure disease, to literally an epidemic on the chokecherries - both the common and the Canada Red cultivar. It has also shown up on the plums grown in the state as well. If your tree or trees have the black, knotty galls that is characteristic of the fungus, prune them out well behind the swollen tissue and burn. Spray with lime sulfur as the new growth emerges. The typical scenario is a couple of branches becoming infected and pruned out; followed by spraying; then some more branches host the fungus, followed by more pruning, until the tree is so disfigured that it is no longer a landscape asset and needs to be removed.
A permanent lawn installed via seed is too late for this spring. This is because the cool season grass that is used (Kentucky bluegrass) will be coming into the hot weeks of June (hopefully!) around the time of germination emergence. While not impossible to accomplish, the combination of heat stress and weed pressure would make it a challenge for a decent lawn to get established.. If cover is wanted, use perennial ryegrass. It germinates in a few days, grows vigorously, and the new cultivars like Goalie and Gettysburg look great. In mid-August, you can then kill everything off with Roundup, and seed into the dead grass with a Kentucky bluegrass mixture or blend for a high-quality lawn. If you selected one of the perennial ryegrass cultivars that I suggested, you will be pleased to know that those two along with Stallion, PS-8990', Dandy, and Dimension are all winter-hardy in North Dakota variety trials. So if the "temporary" planting turned out to be attractive to all concerned, let it stay, unless you are looking for more exercise and ways to spend your money!
Got a soil erosion problem? Try planting daylilies as a ground cover on sloped sites. These plants have a dense, fibrous root systems that will help hold the soil in place, preventing erosion.
The dandelions are making their annual show across the state this week, and many people are asking whether or not now would be the time to control them with an herbicide. Although not the best time, it certainly is easier to find them in your lawn with the bright yellow flowers providing focal points of attack. Use a post-emergent, broadleaf herbicide, not a herbicide/fertilizer combination. There are several on the market, and would include 2,4-D, dicamba, MCPA, or combinations of these. The weeds are growing fast and are succulent from all the rain and cool weather, making them vulnerable to herbicide applications. For those that escape treatment at this time, launch another attack in late August.
Extension Horticulturist and TurfgrassSpecialist