Northeast WI Forest Health

Slime molds and yeasts are bright and slimy

Several reports have recently come in of bright orange slime on trees or on mulch in Brown, Door and Shawano counties. Slime molds and yeasts can make bright colors, usually pink, orange, or yellow. Don’t panic – they don’t harm the tree. Often the orange, slimy areas on trees are associated with sapsucker wounds, where the tree has been bleeding sap on which microorganisms are growing. We see these most during the spring when the weather is moist, but once the weather warms the slime will dry up, leaving just a faint orange tinge to the tree where they were.

Sapsuckers wound trees and return to lick the sap that oozes from the wounds.

Sapsuckers wound trees and return to lick the sap that oozes from the wounds.

A stump is covered by orange slime. Slime molds and yeasts can be orange, pink, or yellow.

Slime molds and yeasts can be orange, pink, or yellow. Photo by: Gerald Vomastic

 

Written by: Linda Williams, forest health specialist, Green Bay, (Linda.Williams@wisconsin.gov), 920-662-5172.

Phomopsis galls on northern red oak

Phomopsis galls are woody, lumpy swellings on the branches and main stem of this northern red oak tree.

Northern red oak with many phomopsis galls on the branches and on the main stem.

Phomopsis galls are large, woody galls caused by a fungus and can be unsightly on the branches of trees (people often notice them in the winter when leaves are off). They occur in hickories, maples, oaks and a few other species. In northeastern Wisconsin, I find them most commonly on hickory, but in some areas northern red oaks can be heavily galled. Counties where I’ve seen these large galls on northern red oak include Oconto, Oneida, Shawano and Vilas. Continue reading “Phomopsis galls on northern red oak”

Eastern spruce dwarf mistletoe

Eastern spruce dwarf mistletoe (Arceuthobium pusillum), is a parasitic flowering plant that can be very damaging to black spruce, although it can also attack other spruces. Occasionally you’ll see it on other species growing amidst spruce such as tamarack, white pine, red pine, jack pine, or balsam fir. Continue reading “Eastern spruce dwarf mistletoe”

Forest tent caterpillar update

Forest tent caterpillars do not make web nests but may congregate and rest in groups on the bark.

Forest tent caterpillars do not make web nests but may congregate and rest in groups on the bark.

Caterpillars hatch from the eggs of a forest tent caterpillar egg mass.

Caterpillars hatch from the eggs of a forest tent caterpillar egg mass.

Forest tent caterpillars are hatching. Egg mass surveys were conducted in Iron, Ashland, Bayfield, Sawyer, Polk, Washburn, Douglas and Burnett counties, and no egg masses were observed. Surveys in Vilas, Oneida and Forest counties found very few egg masses.

Based on this information we expect low numbers and minimal defoliation again this year, but please let us know if you see forested areas with more significant defoliation.

Written by: Linda Williams, forest health specialist, Green Bay, (Linda.Williams@wisconsin.gov), 920-662-5172.

 

Wind and hail damage caused by the April 9, 2017 storm

The National Weather Service local storm reports map shows hail was most commonly reported, with some tree damage, and one tornado (west of Wausau).

The National Weather Service local storm reports map shows hail was most commonly reported, with some tree damage, and one tornado (west of Wausau).

During the night of April 9-10, 2017 a strong line of storms moved through Wisconsin. Reports ranged from pea sized to tennis ball sized hail, with most stating quarter sized hail. Immediately following the hail, winds picked up and straight line winds took down trees in a number of areas around Oneida and Vilas Counties. The National Weather Service reports that there was a tornado touch down west of Wausau, and reports of tree damage showed up in the National Weather Service’s local storm reporting page.

Damage to trees from hail was most noticeable on the conifers which had needles knocked off, creating a green carpet below the trees. Fine twigs on white pines were damaged by the hail and some fine branch mortality may occur if the twigs were damaged badly enough. Damaged red pine may be more prone to getting diplodia where the twigs were wounded.

Hail wounds on fine branches of white pine appear as dents with cracks in the bark. Those cracks will dry further as spring progresses and the cracked areas will increase slightly in size.

April 9 hail wounds on white pine branches (yellow arrows) appear small but will dry, and the bark will crack further as spring progresses. Some branch dieback may occur.

Hail wounds on young aspen and the fine branches of mature aspen from the April 9-10 storm appear as scuffed bark (yellow arrows). These will callus over relatively quickly.

April 9 hail wounds on young aspen and the fine branches of mature aspen appear as scuffed bark (yellow arrows). These will callus over relatively quickly.

Small wounds on young aspen should callus over.

 

 

 

 

 

 

 

Written by: Linda Williams, forest health specialist, Green Bay, (Linda.Williams@wisconsin.gov), 920-662-5172. 

Emerald ash borer trapping by a few northern county forestry departments

Douglas, Oneida, and Sawyer County Forestry Departments will be trapping emerald ash borer on select sites across their properties this year. As needed, the DNR Forest Health Program and the Department of Agriculture, Trade and Consumer Protection (DATCP) will provide guidance to county forest departments that are responsible for purchasing, installing and monitoring their EAB purple prism traps.

Any new EAB detections will be tracked at the state level and may be used by forest managers to prioritize stand management based on EAB proximity, and by communities to inform the timing of ash management in community forests.

The abundance of ash forest resources and limited known distribution of EAB in the state’s north spurred interest by these counties to continue trapping.

Written by Paul Cigan, forest health specialist, Hayward (Paul.Cigan@Wisconsin.gov), 715-416-4920.

Historical – what happened 50 years and 25 years ago in the forest health world?

50 years ago – 1967 – Pine Bark Beetles – Ips sp.

Little damage from bark beetles was encountered in the Northwest, West Central and East Central areas. Damage in the east central counties was restricted to trees that suffered from drought in 1966. Advance reproduction was destroyed in two Jackson County timber sale areas (West Central Area) where pulp operations continued through the summer and wood was left in piles until bark beetles had emerged. Continue reading “Historical – what happened 50 years and 25 years ago in the forest health world?”