My Minnesota Woods » Fraxinus

Emerald Ash Borer Update

Philip Potyondy — Tue, 09 Jun 2009 06:50:18 +0000

MDA survey finds 59 St. Paul trees infested with emerald ash borer

A multi-agency survey found 59 trees infested with emerald ash borer in and around the St. Anthony Park neighborhood where the pest was first discovered in May. All 59 trees are within a half mile of the first infestation site. Crews have already removed the 59 trees. Read the recent news release.

Monitoring efforts using purple cardboard traps and “trap trees” is underway.

Homeowners are asked to join the effort by watching their ash trees for signs of infestation. These signs include:

dieback of leaves in the upper third of the tree’s branches
heavy woodpecker activity
D-shaped exit holes in the bark
S-shaped tunnels under the bark
water shoots on the trunk

Think you might have it?

If you think you might have Emerald Ash Borer use his checklist(pdf) to determine if you should get in touch with an EAB First Detector.

Minnesota Department of Agriculture Quarantine

On May 15th, 2009 the quarantine (previously applied to Houston) added Ramsey and Hennepin counties to prevent the spread of Emerald Ash Borer to new areas through the movement of infested wood and tree parts. Besides applying to all ash tree parts, the regulations apply to all non-coniferous firewood. Read more about the quarantine(pdf).

Don’t remove your healthy ash trees

MDA reminds homeowners that it is not necessary to remove healthy ash trees. Homeowners with questions about disposing of ash tree material should contact their city forester for guidance. Improper disposal of infested ash material could accelerate the spread of EAB.

What does EAB mean for the woodland owner?

Should you try to harvest your ash as quickly as possible? How should you manage your forest? Should you just let nature take its course? There are no simple answers to such questions, but the Michigan State University Extension put together a helpful publication to help woodland owners prepare for EAB.

For more information

University of Minnesota Emerald Ash Borer Page

Minnesota Department of Agriculture Emerald Ash Borer Site

Information for homeowners from emeraldashborer.info

Emerald ash borer discovered in St Paul, MN

Eli Sagor — Thu, 14 May 2009 19:49:09 +0000

The Minnesota Department of Agriculture has announced that EAB has been discovered in St Paul, Minnesota. There’s a news conference at 3:30 today at Hampden Park in St Paul. (via @mnagriculture on Twitter). We’ll provide updates as we’re able.

Extension’s EAB page has links to help Minnesota landowners and citizens prepare for EAB.

Update: MDA has a press release on the Minnesota EAB discovery here.

More about Emerald Ash Borer:

EAB and the future of the Minnesota woods
EAB prevention, detection, and rapid response
Emeraldashborer.info
EAB: Invader at our doorsteps. 6-minute video by MDA.
Do I have Emerald Ash Borer? (PDF)
Ash Tree ID (PDF)
Native borers & look-alikes (PDF)
EAB Signs & Symptoms (PDF)
A Reference for Recognizing Insect Galleries in EAB Detection Trees in Minnesota (PDF: 3MB)
Link to an August 2008 video news release about EAB

Minnesota's ash resource & markets

Eli Sagor — Tue, 10 Feb 2009 16:08:46 +0000

Keith Jacobson of the Minnesota DNR – Forestry Utilization & Marketing unit has just updated his brief overview of Minnesota’s ash resource and markets. This just came out by email today, and is dated February 2009. Download a PDF copy here.

Collecting Minnesota ash seed: 2009 update

Eli Sagor — Tue, 16 Sep 2008 16:44:53 +0000

Update: September 2009

Emerald ash borer (EAB), an invasive species, threatens to kill Minnesota’s ash trees. In response, Andrew David, a University of Minnesota forest genetics researcher, and Mike Reichenbach, forestry educator with University of Minnesota Extension, began a project to protect the genetic diversity of ash in Minnesota.

Black ash stand near Cohasset, MN

Seed collected from wild-grown ash trees will be sent to one of three seed storage facilities in Colorado, Georgia or Iowa depending on the amount of seed collected. This seed collection effort is a proactive response to the presence of EAB in Minnesota and the upper Great Lakes region. This conservation effort will preserve the genetic variation for a future point in time when EAB can be controlled and ash species can be reintroduced to Minnesota using locally adapted seed sources.

How to collect and contribute seed

UMN Assistant Scientist Egon Humenberger with green ash seed collected in 2008.

Ash seed has been ripening all summer and will be ready to pick when the seed cavity is completely filled and the seed coat is brown. Collection of seed typically begins about September 21^st and can continue through much of the fall. Black ash seed is the hardest to collect because it is difficult to judge ripeness and the seed begins to fall with the leaves. The best time to collect black ash seed is from 1 week prior to leaf fall to approximately 2 weeks after all leaves have dropped.

In contrast green ash seed will remain on the tree for awhile after the leaves have fallen allowing collections into late fall. It will be easier to collect from trees before the seed is scattered by winds and rain. Persons wishing to collect seed should watch the ash seed collection webinar found listed under the webinars tab at http://forest.nrri.umn.edu/ash. The ash seed collection form can also be downloaded here.

Value of ash to Minnesota; ongoing threat of EAB
Minnesota is host to three species of ash: white ash, green ash and black ash. While white ash is an upland species found along the Mississippi River in southeast Minnesota; both black and green ash are common lowland hardwoods found throughout the majority of the state. Ecologically, black and green ash are the most important hardwoods in the lowland forest community. They represent 51 percent of the lowland hardwood cover type in Minnesota. Black ash is very important in native cultures as a source of wood for ash baskets. Both black and green ash provide a source of pallet, saw and veneer logs. All of Minnesota’s native ash species are threatened by EAB.

EAB was most likely introduced to the region when it was transported on wood packaging of an overseas shipment from Asia in 2002 to the Detroit, Michigan and Windsor, Ontario area. Within the United States the insect is most often transported on firewood. As of August, EAB has been found in Illinois, Indiana, Maryland, Michigan, Missouri, Ontario, Ohio, Pennsylvania and Wisconsin. It has been responsible for the death of over 20 million ash trees despite quarantines on moving nursery stock and firewood out of infected areas.

This conservation effort will preserve the genetic variation for a future point in time when EAB can be controlled and ash species can be reintroduced to Minnesota using locally adapted seed sources.

Click for much more information on emerald ash borer in Minnesota. To get involved in seed collection, contact Mike Reichenbach, (888) 241-0724, reich027@umn.edu; or Gary Wyatt, (888) 241-3214, wyatt@umn.edu, both with University of Minnesota Extension.

Minnesota's northern hardwoods forest type

Mel Baughman — Fri, 20 Apr 2007 23:53:03 +0000

Products and Uses

The northern hardwoods forest type includes numerous tree species. Sawlogs and veneer logs are the major wood products, but some species also are harvested for pulpwood. Maple syrup is made from sugar maple sap. Wildlife found in a northern hardwood forest may include deer, bear, squirrel, ruffed grouse, and woodcock.

Growing Conditions

Species composition of a northern hardwood forest varies by site and geographic range. Species may include sugar maple, American basswood, white ash, black ash, yellow birch, red maple, and elms. Occasionally aspen, paper birch, balsam fir, and northern red oak are important. Beech and eastern hemlock occur from Michigan eastward.

Sugar maple, beech, hemlock, and balsam fir are very shade tolerant; basswood is tolerant; yellow birch, white ash, red maple, and red oak are moderately tolerant; black ash, paper birch, and aspen are intolerant. Elms, black ash, yellow birch, red maple, eastern hemlock, and balsam fir survive best on high-moisture sites. Sugar maple, white ash, basswood, and beech generally are confined to better drained soils. The best timber is found on moist, well-drained, fertile, loamy soil. The poorest sites occur on soils that are infertile, dry, shallow, or swampy.

Range of sugar maple.

Regeneration

Northern hardwoods can be regenerated by a wide range of systems depending on the species to be favored. If high-quality, very shade-tolerant species are desired, use single-tree selection or group selection methods. After a selection harvest, the residual basal area should be approximately 80 square feet per acre.

If you prefer an even-aged stand dominated by sugar maple, use a two-cut shelterwood system. Harvest in winter and leave 60 percent crown cover after the first harvest. Make the second cut after advance regeneration is 2 to 4 feet high. If you prefer a greater variety of species, use a two-cut shelterwood system, but first eliminate all reproduction present before cutting, harvest in any season except summer, scarify the site during harvest, leave 70 to 80 percent crown cover, remove undesirable seed sources, and make the second cut after advance regeneration is 2 to 4 feet high.

Planting seedlings is rarely necessary, but is appropriate for open fields or under a shelterwood to change the species composition. In open fields plant only in fertile, well-drained soils. Thoroughly disk before planting, plant tap-rooted species such as white ash and northern red oak, plant only when there is good soil moisture, and control weeds for 1 to 3 years after planting. Under shelterwoods, kill undesirable understory plants and plant in the most open areas immediately after site preparation.

Where aspen is mixed with more shade-tolerant northern hardwood species, decide whether to encourage either aspen or the other species. If there is an overstory of aspen and an understory of hardwoods, you can favor the aspen by clearcutting the stand to stimulate root suckering. Favor hardwoods by removing the aspen when the understory hardwoods are 1 to 3 inches DBH, taking great care to avoid damaging the hardwoods. If the aspen has little commercial value, consider killing it with herbicides and letting it stand.

If aspen and other hardwoods are of equal size, aspen can be favored by clearcutting the stand. If aspen is scarce but desirable, follow the harvest with burning or shallow scarification to create an aspen seedbed. To encourage hardwoods, thin or harvest the stand according to the stocking chart for even-aged management of northern hardwoods.

Intermediate Treatments

When following the single-tree selection system, use Table 8 to determine the approximate basal area and number of trees to leave after each harvest. Remove poor quality trees and undesirable species during the harvest.

Pests

Insect pests vary due to the diverse species composition of the northern hardwoods forest type. forest tent caterpillar and a fall defoliator complex (a mixture of up to ten insect species) cause the most problems. No cultural controls are available. Chemical insecticides and BT are effective.

Nectria canker can be common, especially in uneven-aged stands. Reduce damage by maintaining healthy stands and removing infected stems. Sapstreak of maple and heart rots also are serious. To minimize damage from these diseases, reduce damage to roots and stems during cutting operations by using rubber-tired skidders and by harvesting during winter or dry seasons. Remove diseased trees as soon as possible.