Tree workshops in October
This has been quite a year for trees. To start off the year, the ice storm did a tremendous amount of damage to limbs. I am still picking up dead limbs whenever the wind blows. Then all the rainfall and high humidity this summer, the tree diseases have done really well. As if that were not enough, I got an email saying the emerald ash borer is killing off one of my favorite trees, the ash tree.
The emerald ash borer, an invasive pest and a very serious threat to all North American ash trees, has become well-established in North America in the last 10 to 15 years.
The insect easily kills all ash tree species, regardless of health, size or age. First identified in Detroit, Mich., in 2002, the insect has spread rapidly to six eastern states and one Canadian province and is steadily expanding outward.
The insect moves to new areas primarily by the transportation of ash firewood and other ash products, such as pallets, sawlogs etc. Early detection of the insect is extremely difficult. In areas where high numbers of the insect are present, no ash trees are surviving except high-value trees treated individually with insecticides. Currently labeled insecticides also are proving to be ineffective in the long-run because even trees treated with insecticides eventually die from emerald ash borer once populations reach high levels.
With current efforts to contain the ash borer failing, the insect is expected to eventually spread throughout North America wherever ash species are present. Emerald ash borer has cost municipalities, property owners, nursery operators, forest product industries and the related green industry hundreds of millions of dollars from tree removals, other control efforts and the loss of the ash resource.
Considering both the apparent inevitability that the emerald ash borer will reach Nebraska and that the current ash component in many communities and rural areas of Nebraska is already well above recommended levels (maximum of 10 percent of any one group of closely related species), the Nebraska Forest Service no longer recommends planting ash trees in the state.
Ash also will be removed from the lists of acceptable tree species in tree-planting grant programs it administers. In the place of ash, the Nebraska Forest Service strongly promotes diversity in tree plantings and will consider the amount of species diversity in proposals submitted for tree-planting grants.
The Nebraska Forest Service will continue to educate citizens and municipalities about the emerald ash borer and believes strongly that those who wish to plant ash should be informed about the coming impact of the insect and about the benefits of tree diversity for avoiding similar major losses from future invasive pests.
Part of the educator process is a series of Retree Nebraska Workshops. Programs will be held in North Platte at the Mid-Plains Community College Campus on October 10th and at the Hall County Extension office in Grand Island on October 11th. There is an early bird registration of $40 before September 24 and it is $60 after the 24th. For more information contact the UNL Extension office in Phelps County at (308)995-4222 or check out the website arboretum.unl.edu.
