Skip to Main Content
Oak mortality associated with crown dieback and oak borer attack in the Ozark HighlandsAuthor(s): Zhaofei Fan; John M. Kabrick; Martin A. Spetich; Stephen R. Shifley; Randy G. Jensen
Source: Forest Ecology and Management. 255: 2297-2305.
Publication Series: Scientific Journal (JRNL)
Station: Northern Research Station
PDF: View PDF (870.3 KB)
DescriptionOak decline and related mortality have periodically plagued upland oak-hickory forests, particularly oak species in the red oak group, across the Ozark Highlands of Missouri, Arkansas and Oklahoma since the late 1970s. Advanced tree age and periodic drought, as well as Armillaria root fungi and oak borer attack are believed to contribute to oak decline and mortality. Declining trees first show foliage wilt and browning, followed by progressive branch dieback in the middle and/or upper crown. Many trees eventually die if severe crown dieback continues. In 2002, more than 4000 living oak trees !Y11 cm dbh in the relatively undisturbed mature oak forests of the Missouri Ozark Forest Ecosystem Project (MOFEP) were randomly selected and inventoried for tree species, dbh, crown class, crown width, crown dieback condition (healthy: <5% crown dieback, slight: >5-33%, moderate: 33-66%, and severe: >66%) and number of emergence holes created by oak borers on the lower 2.4 m of the tree bole. The same trees were remeasured in 2006 to determine their status (live or dead). In 2002, about 10% of the red oak trees showed moderate or severe crown dieback; this was twice the percentage observed for white oak species. Over 70% of trees in the red oak group had evidence of oak borer damage compared to 35% of trees in the white oak group. There was significant positive correlation between crown dieback and the number of borer emergence holes (p < 0.01). Logistic regression showed oak mortality was mainly related to crown width and dieback, and failed to detect any significant link with the number of oak borer emergence holes. Declining red oak group trees had higher mortality (3 or 4 times) than white oaks. The odds ratios of mortality of slightly, moderately, and severely declining trees versus healthy trees were, respectively, 2.0,6.5, and 29,7 for black oak; 1.8, 3.8, and 8.3 for scarlet oak; and 2.6, 6.5 and 7.1 for white oaks.
- Check the Northern Research Station web site to request a printed copy of this publication.
- Our on-line publications are scanned and captured using Adobe Acrobat.
- During the capture process some typographical errors may occur.
- Please contact Sharon Hobrla, email@example.com if you notice any errors which make this publication unusable.
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationFan, Zhaofei; Kabrick, John M.; Spetich, Martin A.; Shifley, Stephen R.; Jensen, Randy G. 2008. Oak mortality associated with crown dieback and oak borer attack in the Ozark Highlands. Forest Ecology and Management. 255: 2297-2305.
Keywordsoak decline, mortality, oak borer, logistic regression
- Proceedings of the seventh California oak symposium: managing oak woodlands in a dynamic world
- Sustaining oak forests in eastern North America: regeneration and recruitment, the pillars of sustainability
- Efficacy and associated factors of even- and uneven-aged management to promote oak regeneration in the Missouri Ozarks
XML: View XML