In the past several years, Texas trees have taken a heavy hit from fire blight. It is a condition causing leaves to brown and dry up resulting from a bacterial infection. The leaves look like they have been scorched by fire, thus the name “fire blight.” (( Fire Blight of Ornamental Pears. Texas Plant Disease Diagnostic Lab. Texas A & M Agrilife Extension. Accessed 2-2-2015. )) Affecting trees in the Rose family, pear and quince are particularly susceptible; however, other trees such as apple, crabapple, firethorns, loquats, raspberry, hawthorn, spirea, cotoneaster, toyon, juneberry, serviceberry, and mountain ash can also succumb to the disease. (( Pests in Gardens and Landscapes: Fire Blight. Homes, Gardens, Landscapes, and Turf. University of California Agriculture & Natural Resources. 7-11. Accessed 2-2-2015. )) (( Fire Blight. Wikipedia. Accessed 2-2-2014. http://en.wikipedia.org/wiki/Fire_blight ))
Causes of Fire Blight
Fire blight is caused by bacteria that are spread from tree to tree by birds and insects during the spring blooming season. (( Fire Blight Outbreak Affects Area Flowering Pears. Arborilogical Services, Inc. 6-4-2012. Accessed 2-2-2015. )) Once infected, the bacteria infiltrates the plant’s vascular system, spreading out through the branches and eventually the root. If the root is damaged by the infection, the plant will die. (( Fire Blight. Wikipedia. Accessed 2-2-2014. http://en.wikipedia.org/wiki/Fire_blight ))
Identifying Fire Blight
The first hint that your tree is affected by fire blight is leaves which turn brown and black, curling and then shriveling. Twigs and stems will wilt from the leaf tip downward, blackening and curling into the form of a “shepherd’s hook.” The branches will form sunken lesions and cankers, eventually spreading throughout the branch. ((Fire Blight of Ornamental Pears. Texas Plant Disease Diagnostic Lab. Texas A & M Agrilife Extension. Accessed 2-2-2015. ))
Fire Blight Treatment
Fire blight cannot be cured; however, it can be prevented by spraying susceptible trees with bactericides in the spring just as the tree begins to bud. (( Fire Blight Outbreak Affects Area Flowering Pears. Arborilogical Services, Inc. 6-4-2012. Accessed 2-2-2015. ))
For trees that already have infected areas, the damaged areas will need to be removed. The Texas A & M Agrilife Extension Agency recommends the following: (( Fire Blight of Ornamental Pears. Texas Plant Disease Diagnostic Lab. Texas A & M Agrilife Extension. Accessed 2-2-2015. ))
Cut an infected branch 8 to 12 inches below the visible injury or canker. To avoid spreading bacteria during pruning, sanitize the pruning tool before each cut with a 10% solution of bleach (one part bleach to nine parts water). To prevent rust, dry and oil tools after use.
Fire blight control
In order to prevent and control fire blight, a proactive tree maintenance program is necessary. Stop by the Kingwood Garden Center for our recommended fire blight spray and treatment. Not sure if your tree has fire blight or something else? Bring in an affected branch to the Garden Center for identification.
