Laurel wilt, caused by Raffaelea tauricola. has been responsible for extensive losses of redbay (Persea borbonia) in South Carolina and Georgia since 2003. Symptoms of the di.sease have been noted in other species of the Lauraceae such as the federally endangered pondberry (Lindera melissifolia) and the threatened pondspice (Litsea aeslivitlis). Pondberry and pondspice seedlings were inoculated with R. tatiricota from redbay. and both species proved highly susceptible to laurel wilt. Field assessments found substantial mortality of pondberry and pondspice, but in many cases the losses were not attributable to laurel wilt. R. lauricola was isolated from only 4 of 29 symptomatic pondberry plants at one site, but the fungus was not recovered from three plants at another site. R. lauricola was isolated from one of two symptomatic pondspice plants at one site, and from five of 11 plants at another site, but not from any plant at a third site. Insect bore holes, similar to those produced by Xyleborus glahratus (the vector of laurel wilt), were found in some pondberry and pondspice stems, but adults were not found. Damage caused by Xylosandrus cotnpaclus was found in pondberry stems, but this ambrosia beetle does not appear to be a vector of R. lauricola. Xyleboriniis .ut.xeseni adults were found in a dying pondspice with laurel wilt, and R. lauricola was recovered from two of three adults. Isolates of R. lauricola frotn pondberry. pondspice. and X. sa.xe.'ieni had rDNA sequences that were identical to previously characterized isolates, and inoculation tests confirmed that they were pathogenic to redbay. Because pondberry and pondspice tend to be shrubby plants with small stem diameters, these species may not be frequently attacked by X. glabratus unless in close proximity to larger diameter redbay.

Laurel wilt disease, caused by Raffaelea lauricola (T.C. Harr., Fraedrich & Aghayeva sp. nov.), which is a fungal symbiont of the nonnative redbay ambrosia beetle (Xyleborus glabratus Eichhoff), has caused widespread mortality of native redbay (Persea borbonia (L.) Spreng) in Georgia, South Carolina, and Florida since 2002. The disease has been noted on other species in the Lauraceae including sassafras in Georgia (1), and more recently, on avocado and camphor in Florida (4). Since 2005, wilted shoots, branch dieback, and tree death have been observed in sassafras trees (Sassafras albidum (L.)) in Liberty, McIntosh, Chatham, Effingham, Bulloch, Evans, and Screven counties in Georgia; Bamberg, Beaufort, Charleston, Colleton, Hampton, and Orangeburg counties in South Carolina; and Putnam County in Florida. Symptomatic sassafras trees ranged from 1 to 12 m high and 2.5 to 25 cm in diameter at breast height. In contrast to red bay trees that retain wilted foliage, symptomatic sassafras defoliate rapidly as trees wilt and die. Multiple symptomatic ramets originating from a common root system have been observed. Removal of bark from stem and root sections from wilted trees revealed black-to-brownish staining in the sapwood, characteristic of laurel wilt. Wood chips from symptomatic areas of branches and roots were surface sterilized and plated on cycloheximide-streptomycin malt agar as previously described (1) and R. lauricola was routinely isolated. Small subunit (18S) sequences from rDNA were amplified by PCR and sequenced using primers NS1 and NS4 (3) for isolates from sassafras from Florida and South Carolina. BLASTn searches revealed homology to Raffaelea sp. C2203 (GenBank Accession No. EU123076, 100% similarity) described by Fraedrich et al. (1) from redbay and later named R. lauricola (2). The small subunit rDNA sequences for these isolates have been deposited into GenBank ( http://www.ncbi.nlm.nih.gov/Genbank/index.html ) and assigned Accession Nos. EU980448 (Florida) and GQ329704 (South Carolina). Koch's postulates have been completed with R. lauricola on this host previously (1). Laurel wilt on sassafras often was geographically isolated from other symptomatic hosts in Georgia and South Carolina and appears to occur on this host independently of proximity to redbay. Further studies to determine the epidemiology of laurel wilt on sassafras, potential resistance, and impact on sassafras life history and distribution are needed. Given the clonal nature of sassafras, the disease would appear to have the potential to move through roots of trees once established in a stand. References: (1) S. W Fraedrich et al. Plant Dis. 92:215, 2008. (2) T. C. Harrington et al. Mycotaxon 104:399, 2008. (3) M. A. Innis et al. PCR Protocols, A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990. (4) J. A. Smith et al. Plant Dis. 93:198, 2009.

Woody plants are typically inventoried in all five levels of the CVS-EEP protocol, although such inventory is optional in Levels 3 and 4. Woody plants fall into two broad categories planted and natural. Planted woody plants (described in blue in the left column in this document) are those intentionally planted as part of a restoration effort, and may have originated as transplants, live-stakes, balled and burlapped plants, potted plants, tublings, or bare-root seedlings. Natural woody plants (described in green in the right column in this document) are those not planted and are sometimes referred to as "volunteers."The CVS-EEP protocol requires positive confirmation (from a planting plan, or previous monitoring records) or strong evidence (e.g., remnants of burlap or potting media) for a woody plant to be considered of planted origin.Without positive confirmation or strong evidence of a woody stem being planted, it is considered to be of natural origin.Three different measurements are taken on plants. Height always refers to the length of the stem, which for vertical stems is the true height. For leaning stems, the height is measured along the length of the stem. Diameter at decimeter height (ddh, always written lowercase) is the diameter of the stem measured at 10 cm in height (which is 10 cm measured along the stem for leaning stems). Diameter at breast height (DBH, always written uppercase) is measured at 1.37 m along the stem, which in the case of a vertical stem is 1.37 m above the ground. Fundamental concepts and inventory procedures differ between planted and natural woody plants.Each planted woody plant is considered and inventoried as a single individual, regardless of the number and size of stems emerging from a common root system. Natural woody plants, in contrast, are inventoried in two broad size categories, seedlings (those plants with no stem achieving breast height) and saplings / trees (those plants with at least one stem achieving a length of at least 1.37 m [breast height for vertical stems]).One or more of height, ddh, and DBH are measured, depending on the size and origin of a plant. No tallies are made for planted stems.A natural woody seedling, like a planted woody plant, is considered and inventoried as a single individual, regardless of the number and size of stems emerging from a common root system. A natural woody sapling/tree with a single stem is also considered and inventoried as a single individual. However, a natural woody sapling/tree with multiple stems may be considered and inventoried as multiple individuals if the stems split below 50cm in height (along the stem). Seedlings are tallied based on three classes of length [height] achieved by the longest [tallest] stem: 10-50cm, 50-100cm, and 100-137cm. Saplings (stems 0-2.5 cm DBH) are tallied based on two DBH classes: 0-1.0 and 1.0-2.5 cm DBH, whereas trees (stems > 2.5 cm DBH) are tallied based on multiple DBH classes starting at 2.5 cm DBH (2. 5-5, 5-10, 10-15, 15-20, 20-25, 25-30, 30-35, 35-40cm, and to the closest cm excee...

Laurel wilt, caused by Raffaelea lauricola, a fungal symbiont of the redbay ambrosia beetle, Xyleborus glabratus, is responsible for extensive mortality of native redbays (Persea borbonia and P. palustris) in the coastal plains of the southeastern United States (1). The wilt also affects the more widespread sassafras, Sassafras albidum, particularly in areas where diseased redbays are common and populations of X. glabratus are high. Because sassafras stems were thought to lack chemicals that are attractive to the beetle, and sassafras tends to be widely scattered in forests, it was believed that the advance of the laurel wilt epidemic front might slow once it reached the edge of the natural range of redbay, which is restricted to the coastal plains of the Gulf and Atlantic Coasts (2). In July and August of 2011, wilt-like symptoms (i.e., wilted and dead leaves, and streaks of black discoloration in the xylem) were observed on 1 to 10 sassafras trees (15 to 23 cm diameter; 6 to 9 m height) at each of three locations, which were approximately 6 km from one another in Marengo Co., Alabama. Samples of the discolored wood from five trees were plated on malt agar amended with cycloheximide and streptomycin (CSMA), and a fungus morphologically identical to R. lauricola was isolated from each tree (1). For confirmation, a portion of the large subunit (28S) of the rDNA region of three of the isolates was sequenced (3); in each case, the sequence matched exactly that of other isolates of R. lauricola (EU123077) from the United States. Symptomatic trees were found at all three sites when revisited in April 2012, and approximately 20 sassafras trees in various stages of wilt were observed at one location, where only one diseased tree had been noted in 2011. Bolts were cut from the main stem of a symptomatic tree, and eggs, larvae, and adults of X. glabratus were commonly found in tunnels, and R. lauricola was isolated from the discolored xylem. Three container-grown sassafras saplings (mean height 193 cm, mean diameter 2.1 cm at groundline) were inoculated as previously described (1) with conidia (~600,000) from an isolate of R. lauricola. Three additional sassafras saplings were inoculated with sterile, deionized water, and all plants were placed in a growth chamber at 25°C with a 15-h photoperiod. Inoculated plants began to exhibit wilt symptoms within 14 days, and at 30 days all inoculated plants were dead and xylem discoloration was observed. Control plants appeared healthy and did not exhibit xylem discoloration. Pieces of sapwood from 15 cm above the inoculation points were plated on CSMA, and R. lauricola was recovered from all wilted plants but not from control plants. This is the first record of laurel wilt in Alabama and is significant because the disease appears to be spreading on sassafras in an area where redbays have not been recorded (see http://www.floraofalabama.org ). The nearest previously documented case of laurel wilt is on redbay and sassafras in Jackson Co., Mississippi (4), approximately 160 km to the south. The exact source of the introduction of X. glabratus and R. lauricola into Marengo Co. is not known. The vector may have been transported into the area with storms, moved with infested firewood, or shipped with infested timber by companies that supply mills in the area. References: (1) S. Fraedrich et al. Plant Dis. 92:215, 2008. (2) J. Hanula et al. Econ. Ent. 101:1276, 2008. (3) T. Harrington et al. Mycotaxon 111:337, 2010. (4) J. Riggins et al. Plant Dis. 95:1479, 2011.

Laurel wilt is a recently described (1) vascular disease of redbay (Persea borbonia (L.) Spreng) and other plants in the family Lauraceae. The wilt is caused by Raffaelea lauricola, a fungus vectored by the nonnative redbay ambrosia beetle (Xyleborus glabratus Eichhoff) (1,2). Since 2003, laurel wilt has caused widespread mortality of redbay in Georgia, South Carolina, and Florida (1) and has recently been found on avocado in Florida (4). Since June of 2007, wilted shoots and branch dieback have been observed in several camphor trees (Cinnamomum camphora (L.) Sieb.) in residential areas of McIntosh and Glynn counties in Georgia and Baker County in Florida. Symptomatic camphor trees ranged from 4.5 to 12 m high and occurred in areas where redbay mortality due to laurel wilt has been frequently observed during the last 2 to 3 years. In some camphor trees, only the smaller branches (<2 cm in diameter) were wilting or dead, whereas in other trees (e.g., Baker County, Florida), the larger branches and substantial portions of the crown were also symptomatic. Rapid wilt that affects entire trees that is usually observed in redbay, has not been observed in camphor. Some camphor trees in residential areas of Jekyll Island, Georgia (Glynn County), where extensive wilt of redbay has occurred, have exhibited only localized wilt of some shoots or branches and other camphors remain asymptomatic. Removal of bark from wilted branch sections revealed black-to-brownish staining in the sapwood, characteristic of laurel wilt. Although no evidence of ambrosia beetles was observed on these samples, more extensive surveys are needed to determine the role of this vector in laurel wilt of camphor. Wood chips from symptomatic areas of branches were surface sterilized and plated on cycloheximide-streptomycin malt agar as previously described (1,4) and R. lauricola was routinely isolated. Small subunit (18S) sequences from rDNA were amplified by PCR and sequenced using primers NS1 and NS4 (3). BLASTn searches revealed homology to R. lauricola C2203 (GenBank Accession No. EU123076, 100% similarity, e-value of 0.0, and a total score of 1,886). The small subunit rDNA sequence for this isolate has been deposited into GenBank ( http://www.ncbi.nlm.nih.gov/Genbank/index.html ) and has been assigned Accession No. EU 853303. The presence of laurel wilt in camphor provides an opportunity to understand the pathogen distribution and possible resistance mechanisms in this host, which could have implications for efforts to remediate the impacts of the disease in redbay and other species in the Lauraceae in the southeastern United States. References: (1) S. W Fraedrich et al. Plant Dis. 92:215, 2008. (2) T. C. Harrington et al. Mycotaxon 104:399, 2008. (3) M. A. Innis et al. PCR Protocols, A Guide to Methods and Applications. Academic Press. San Diego, CA, 1990. (4) A. E. Mayfield, III et al. Plant Dis. 92:976, 2008.

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Callery pear (Pyrus calleryana) is rapidly spreading in the U.S., gaining attention in the last two decades as a serious invasive pest. Recommended control methods include foliar, basal bark, cut-stump and hack-and-squirt application of herbicides, but there are few published studies with replicated data on efficacy. Four readily available herbicidal active ingredients and a combination of two active ingredients were tested for control efficacy against Callery pear in old field areas and loblolly pine understory. Basal bark applications (triclopyr, triclopyr + aminopyralid), foliar applications (glyphosate, imazapyr), and a soil application (hexazinone) effectively killed Callery pear with the exception of hexazinone at one site, where rainfall may not have been optimal. Foliar application of glyphosate provided the most consistent control. Our results demonstrate efficacy of registered herbicide formulations for Callery pear control in two geographic locations and two habitat types. The need for development of integrated pest management programs for Callery pear is discussed.