First Printing 1M, February 2002 Find this and other publications on-line at www.ag.auburn.edu/resinfo/publications/ Information contained herein is available to all persons without regard to race, color, gender, national origin, or religion. REsiSTANCE OF SELECTED CRAPEMYRTLE CULTIVARS TO POWDERY MILDEW AND CERCOSPORA LEAF SPOT AusTIN K. HAGAN, GARY J, KEEVER, CHARLES H. GILLIAM, J, DAVID WILLIAMS, AND GREG CREECH1 INTRODUCTION Brilliant fall color, handsome exfoliating bark, lush foliage, and large showy flower panicles have made crapemyrtle (Lagerstroemia indica) a fixture in landscapes and gardens across Alabama (17). Introduced from China in 1747, crapemyrtles range in size from small shrubs to sizable trees and are widely used in screens, hedges, mass plantings, or as accent or specimen plants. This highly versatile shrub and tree, which blooms throughout much of the summer, is best adapted to well-drained soils on sunny sites in USDA Hardiness Zones 7 to 9 (4,16). In the mid-1950s, Lagerstroemiafauriei was introduced from Japan and was later hybridized with L. indica to produce a number of highly desirable selections of crapemyrtle. In addition, a number of improved cultivars of crapemyrtle (L. indica) have also been released into the nursery market. Powdery mildew (Erysiphe lagerstroemia) is the most widely recognized and common disease on crapemyrtle (1). Although this disease is not a serious threat to the health of established plants, a severe outbreak of powdery mildew can greatly detract from the beauty of crapemyrtle in landscape plantings. Powdery mildew, which usually appears in late spring or early summer, is easily recognized by the appearance of white to buffcolored colonies of E. lagerstroemia on leaves, tender shoots, and bud scales on the blooms. On heavily mildewed crapemyrtle, twisting of the leaves, flower bud abortion, and shoot dieback may also be seen (1). Cercospora leaf spot (Cercospora lythracearum), which is not as well known as powdery mildew, may actually be more common than the latter disease (2). Circular to irregular brown spots, which first appear on mature leaves in late June to early July, are not noticeable until August. As 1 Hagan is Professor of Entomology and Plant Pathology; Keever, Gilliam, and Williams are Professors of Horticulture, Creech is Research Associate of Horticulture; all at Auburn University. 4 ALABAMA AGRICULTURAL EXPERIMENT STATION the spots enlarge, the leaves turn yellow to bright red and quickly fall to the ground. Typically, leaf spotting and defoliation start on the lower limbs and gradually spread upward through the plant canopy until all but the youngest leaves at the shoot tips are lost. The heavy leaf shed associated with damaging disease outbreaks can greatly detract from the brilliant fall color display of leaf spot-susceptible crapemyrtle. Disease resistance is an effective, inexpensive, and pesticidefree method of producing and maintaining plantings of crapemyrtle in the nursery and landscape. As indicated above, a number of improved cultivars in the three crapemyrtle taxa (L. indica, L. fauriei, and L. indica x fauriei) were selected for superior horticultural characteristics as well as tolerance or resistance to powdery mildew (5,6,7,8,9,10,11,12,13,14). In recent studies, Knox et al. (16) and Windham et al. (18) did not see significant colonization of the leaves of hybrid crapemyrtle cultivars by the powdery mildew fungus. In Louisiana, Holcomb (15) noted that several of the hybrid selections (L. indica x fauriei) and a number of cultivars of crapemyrtle (L. indica) were susceptible to powdery mildew and Cercospora leaf spot. In the same study, the hybrid cultivars 'Tonto', 'Tuscarora', and 'Catawba' were resistant to both powdery mildew and Cercospora leaf spot (15). In a landscape planting in Auburn, Alabama, selections in three crapemyrtle taxa (L. indica, L. fauriei, and L. indica x fauriei) were screened for their susceptibility to powdery mildew and Cercospora leaf spot. MATERIALS AND METHODS A field planting of 45 selections of crapemyrtle in the taxa L. indica, L. fauriei, and L. indica x fauriei was established on the Alabama Agricultural Experiment Station (AAES) unit on the campus of Auburn University, Alabama (USDA Hardiness Zone 8a). Before planting, soil fertility and pH were adjusted according to the recommendations of a soil fertility assay of the Auburn University Soil Testing Laboratory. In March 1993, bare-root liners were planted in full sun in a Marvyn loamy sand on eight-foot centers in rows spaced 12 feet apart. The test site was sloped slightly to the southeast. The experimental design was a randomized complete block with six, two-tree replications. A trickle irrigation system with RESISTANCE OF SELECTED CRAPEMYRTLE CULTIVARS 5 two emitters per tree was installed at the time of tree establishment, and the trees were watered as needed. Twice each spring, approximately six ounces of 13-13-13 analysis fertilizer was uniformly distributed around the base of each plant. A tank-mix ofPrincep 4L and Surflan A.S. pre-emergent herbicides was applied at label rates in March 1996 and March 1997. Hand weeding and directed applications of label rates of Roundup Pro herbicide were used to control escape weeds. Alleys between the rows were periodically mowed. In 1995, all trees were mulched with two inches of aged pine bark. During the winters of 1995 and 1996, each tree was lightly pruned to enhance form and structure. Within two years of planting, the causal fungi of powdery mildew (E. lagerstroemia) and Cercospora leaf spot (C. lythracearum) were well established in this planting of crapemyrtle. Powdery mildew ratings were recorded on July 28, 1995: June 4, 1996: and June 25, 1997 using a scale of 0 to 4 (0 = no disease, 1 = 1 to 25 %, 2 = 26 to 50%, 3 = 51 to 75 %, and 4 = 76 to 100% of the leaves, shoots, and buds damaged or colonized by E. lagerstroemia). The severity of Cercospora leaf spot was evaluated on Septel)lber 15, 1995; September 4, 1996; and August 29, 1997 using the Barratt and Horsfall Rating System (1 = 0%, 2 = 0 to 3%, 3 = 3 to 6%, 4 = 6 to 12%, 5 = 12 to 25 %, 6 = 25 to 50%, 7 =50 to 75 %, 8 = 75 to 87 %, 9 = 87 to 94%, 10 = 94 to 97%, 11 = 97 to 100%, and 12 = 100% of the leaves exhibiting characteristic symptoms or prematurely lost due to this disease). RESULTS By mid-May each year, the typical fluffy white colonies of the powdery mildew fungus were seen on the young leaves and shoots of the mildew-susceptible crapemyrtle cultivars. Generally, the occurrence of powdery mildew peaked between mid-June and late July. The fungal colonies persisted on leaves of susceptible cultivars until early fall. Although symptoms of Cercospora leaf spot first appeared on highly susceptible cultivars as early as June, spotting of the leaves and premature leaf shed usually were not noticeable on most cultivars until mid-August to early September. Spotting of the leaves and leaf shed continued through the fall until the first hard frost in late October or early November. 6 ALABAMA AGRICULTURAL EXPERIMENT STATION As a group, the cultivars of crapemyrtle (L. indica) were more susceptible to powdery miidew than were the hybrid crapemyrtles (L. indica x fauriei) and L.fauriei 'Fantasy' (Tables 1 and 2). Powdery mildew ratings for all of the hybrid crapemyrtle cultivars and L. fauriei 'Fantasy' were similar in all three years. In 1995 and 1996, the severity of Cercospora leaf spot averaged across all cultivars of L. indica and L. indica xfauriei did not differ. Cercospora leaf spot damage levels for L. fauriei 'Fantasy' were lower than the averaged ratings for the other two crapemyrtle taxa. Considerable differences in the incidence of powdery mildew were seen among the 20 cultivars of L. indica (Table 1). Also, disease incidence differed considerably from year to year on many of these cultivars, especially on those highly susceptible to powdery mildew. In two of three years, heavy colonization of the leaves and shoots, as indicated by disease ratings of 2.0 or above, was seen on 'County Red' crapemyrtle (Table 2). High levels of disease also were seen in one of three years on 'Carolina Beauty' , 'Raspberry Sundae', 'Wonderful White' , 'Gray's Red', 'Orbin Adkins', and 'Seminole'. Noticeable mildewing of the leaves and shoots, which was indicated by dis~ase ratings between 1.0 and 2.0, was seen in at least one year on an additiona111 selections of L. indica crapemyrtle. 'Cherokee' remained mildew-free, while low levels of powdery mildew were seen each year on 'Glendora White'. In at least one year, considerable Cercospora leaf spot-related spotting of the leaves and early leaf shed were observed on nearly all cultivars of L. indica (Table 2). By early fall, 'OrbinAdkins' and 'Wonderful White' consistently suffered severe defoliation and heavy spotting of the few remaining leaves found near the shoot tips. As indicated by disease ratings above 5.0 in at least two years, 'Raspberry Sundae', 'Powhatan', 'Majestic Beauty', 'Hardy Lavendar' , and 'Carolina Beauty' also proved highly susceptible to Cercospora leaf spot. In contrast, leaf spotting and early leaf shed, though noticeable, were limited to the lower quarter of the canopy of 'Glendora White', 'Gray's Red', and 'Velma's Royal Delight'. As expected, the occurrence of powdery mildew on many of the hybrid (L. indica xfauriei) crapemyrtle was generally very low (Table 2). Light to moderate outbreaks of this disease, as indicated by disease ratings between 0.5 and 1.0, were recorded in two years for 'Zumi' and in one year for 'Hopi' and 'Pecos'. Of all the cultivars of hybrid crapemyrtle, only 'Caddo' remained free of powdery mildew in all three years. In two of RESISTANCE OF SELECTED CRAPEMYRTLE CULTIVARS 7 TABLE 1. SuSCEPTIBILITY OF CRAPEMYRTLE (L. Blossom color Red Purple Red Red Red White Red Lavender White Light pink White Pink/ white edges Pink Purple Deep red Red Pink Purple Pink/red White INDICA) CULTIVARS TO POWDERY MILDEW AND CERCOSPORA LEAF SPOT Cultivar L. indica Carolina Beauty Catawba Centennial Spirit Cherokee Country Red Glendora White Gray's Red Hardy Lavender Majestic Beauty Near East Orbin Adkins Peppermint Lace Growth Powdery mildew2 habit' 1995 1996 1997 LT ST ST SD ST SD ST LT SD ST ST D ST ST SD ST ST . D ST LT 2.3 0.7 1.6 0.0 2.8 0.4 2.2 1.1 1.7 Cercospora leafspot3 1995 1996 1997 5.8 3.6 2.2 2.3 4.0 2.3 3.5 4.2 3.7 5.0 5.7 4.0 2.7 3.4 4.6 2.1 3.3 2.0 3.7 5.0 6.3 4.6 4.8 4.0 4.6 3.7 3.9 5.1 5.3 5.4 6.8 5.6 4.5 5.5 5.7 4.0 5.6 3.3 4.4 6.8 5.8 3.0 5.0 0.3 2.4 1.7 1.8 1.3 3.1 0.6 0.8 1.2 1.9 2.4 1.6 0.1 0.0 0.0 2.5 0.4 0.8 1.1 1.0 0.0 0.7 1.0 0.3 1.1 1.5 1.2 0.3 0.6 1.3 1.5 1.2 1.2 0.8 NR4 0.9 0.5 1.0 1.8 1.0 1.3 1.2 1.6 0.9 1.8 1.5 1.3 2.2 1.4 1.8 1.3 NR 5.0 3.8 4.3 5.0 5.0 4.7 6.8 4.9 3.6 5.5 5.3 4.2 4.5 3.7 3.6 6.8 Potomac Powhatan Raspberry Sundae Regal Red Seminole Velma's Royal Delight William Toovey Wonderful White 'D =dwarf form (3-5 feet), SD = semi-dwarf (5-10 feet), ST= small tree (10-20 feet), LT =large tree (20 feet or larger). 2 Powdery mildew was rated on a scale of 0 to 4 where 0 = no disease, 1 = 1 to 25%, 2 = 26 to 50%, 3 =51 to 75%, 4 = 76 to 100% of the leaves damaged or colonized E. lagerstroemia. 3 Cercospora leaf spot was evaluated using the Barratt and Horsfall System: 1 = 0%, 2 = 0 to 3%, 3 = 3 to 6%, 4 = 6 to 12%, 5 = 12 to 25 %, 6 = 25 to 50%, 7 =50 to 75%, 8 = 75 to 87%, 9 = 87 to 94%, 10 = 94 to 97%, 11 = 97 to 100%, 12 = 100%. three years, the characteristic white colonies of the fungus E. lagerstroemia were not seen on the leaves, flower buds, or shoots of 'Sarah's Favorite', 'Comanche', 'Osage', 'Acoma', 'Tonto', 'Souix', 'Lipan', or 'Natchez' . On the remaining hybrid crapemyrtle cultivars, as well as on L. fauriei 'Fantasy', the incidence of powdery mildew was limited to a single or a few widely scattered colonies of the fungus on the leaves, tender shoots, and flower buds. Although most hybrid crapemyrtle selections are highly resistant to powdery mildew, only a handful were resistant to Cercospora leaf spot 8 ALABAMA AGRICULTURAL EXPERIMENT STATION Fig. 1 Cottony white growth or hyphae of powdery mildew fungus on leaves of crapemyrtle. Fig. 2 Heavy powdery mildew outbreak on 'Raspberry Sundae' crapemyrtle. Fig. 3 In a Cercospora leaf spot infection, circular to irregular brown spots appear on the older leaves near the base of the plant. Later, these spotted leaves begin to turn yellow to bright red before they fall to the ground. Fig. 5 Cercospora leaf spot-susceptible crapemyrtles such as 'Acoma' may be heavily defoliated and have poor fall color. Fig. 4 Symptoms of Cercospora leaf spot include yellowing and premature loss of the spotted leaves near the base of the tree or shrub. RESISTANCE OF SELECTED CRAPE MYRTLE CULTIVARS 9 Fig. 6 Of the 45 selections of crapemyrtle screened, 'Fantasy' was the most disease resistant. Fig. 7 Other powdery mildew and Cercospora leaf spot resistant selections of crapemyrtle included: clockwise from top right (a) 'Tonto', (b) 'Tuscarora', (c) 'Tuskegee', and (d) 'Velma's Royal Delight'. 10 ALABAMA AGRICULTURAL EXPERIMENT STATION (Table 2). Of the 22 selections of hybrid crapemyrtle, 'Tonto', 'Tuskegee' , and 'Tuscarora' have the highest level of resistance to this disease. In each area, damage on these cultivars and L fauriei 'Fantasy' was confined to light, inconspicuous spotting of the leaves around the base of the plants. Light to moderate spotting of the leaves along with a low level of early leaf shed, as indicated by disease ratings of 2.5 to 3.8, was seen on 'Basham's TABLE 2. SuSCEPTIBILITY OF Blossom color White Lavender Pink Light pink Bright pink Bright pink Coral Pink Lavender Dark pink Lavender White Light pink Pink Pink Dark pink Red Coral pink Dark pink Lavender Lavender Lavender White CRAPEMYRTLE (L, INDICA X FAURIEI ND L. FAURIEI) CuLTIVARS TO PowDERY MILDEw AND CERCOSPORA LEAF SPOT Cultivar L. indica xfauriei Acoma Apalachee Basham 's Party Pink Biloxi Caddo Choctaw Comanche Hopi Lipan Miami Muskogee Natchez Osage Pecos Sarah's Favorite ยท Souix Tonto Tuscarora Tuskegee Wichita Yuma Zumi L. fauriei Fantasy Growth habit' SD ST LT LT SD LT ST. SD ST LT LT LT ST SD LT ST SD LT ST LT SD SD LT -Powdery mildew 21995 1996 1997 0.0 0.2 0.2 0.4 0.0 0.0 0.0 0.2 0.3 0.1 0.2 0.0 0.0 0.4 0.0 0.1 0.1 0.5 0.1 0.3 0.4 1.3 0.4 0.0 0.0 0.2 0.3 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.1 0.0 0.0 0.0 0.0 0.4 0.0 0.0 0.3 0.0 0.1 0.2 0.4 0.8 0.0 0.3 0.4 1.7 0.0 0.7 0.6 0.0 0.4 1.3 0.1 0.0 0.0 0.4 0.2 0.8 0.4 1.8 0.2 Cercospora leafspot1 1995 1996 1997 5.3 2.7 2.8 4.4 2.4 4.5 5.6 3.9 2.9 3.5 4.7 4.3 2.8 2.8 3.5 4.3 2.3 1.7 1.8 2.8 4.9 4.8 1.4 6.3 2.8 2.5 5.3 2.9 4.6 6.6 5.7 5.1 4.7 4.8 4.6 4.0 5.1 3.8 5.2 1.3 2.4 1.5 3.6 5.0 4.4 1.1 6.2 1.3 1.7 4.0 4.6 3.5 4.9 5.4 2.6 3.2 4.2 2.6 1.3 2.6 3.3 1.3 1.2 1.8 1.3 2.6 5.2 3.5 1.7 'D = dwarf form (3-5 feet), SD = semi-dwarf (5-10 feet), ST = small tree (10-20 feet), LT = large tree (20 feet or larger). 2 Powdery mildew was rated on a scale of 0 to 4 where 0 = no disease, 1 = 1 to 25%, 2 = 26 to 50%, 3 =51 to 75%, 4 = 76 to 100% of the leaves damaged or colonized E. lagerstroemia. 3Cercospora leaf spot was evaluated using the Barratt and Horsfall System: 1 = 0%, 2 = 0 to 3%, 3 = 3 to 6%, 4 = 6 to 12%, 5 = 12 to 25%, 6 = 25 to 50%, 7 =50 to 75%, 8 = 75 to 87%, 9 = 87 to 94%, 10 = 94 to 97%, 11 = 97 to 100%, 12 = 100%. RESISTANCE OF SELECTED CRAPEMYRTLE CULTIVARS 11 Party Pink', 'Apalachee', and 'Wichita'. Conversely, the heaviest spotting of the leaves and premature defoliation were noted in at least two of three years on 'Acoma' and 'Comanche'. Cercospora leaf spot ratings of 5.0 or higher were recorded in at least one year for another five cultivars of hybrid crapemyrtle. DISCUSSION Resistance to powdery mildew was one of the major selection criteria used to identify clones of hybrid crapemyrtle for release as part of the U.S. National Arboretum breeding program (5, 6, 7, 8, 9, 10, 11, 12, 13, 14). Beginning with 'Natchez' and 'Muskogee', a total of22 hybrid cultivars have been released (7,8,9,10,11 ,12,13,14 ). Resistance of the cultivars of hybrid crapemyrtle and L. fauriei 'Fantasy' to powdery mildew is far superior to that shown by the selections of L. indica. With the exception of 'Zuni' , 'Pecos', and 'Hopi', the cultivars of hybrid crapemyrtle proved highly resistant or immune to powdery mildew. Typically, similar results have been obtained when the releases from the U.S . National Arboretum were evaluated in the field (15,16,18). Many cultivars of crapemyrtle (L. indica) were moderately or highly susceptible to powdery mildew, while others like 'Glendora White', and 'Cherokee' were highly resistant to nearly immune to this disease. Of the five mildew tolerant cultivars of L. indica released by the U.S. National Arboretum, light to moderate mildew development was recorded in at least one year on 'Powhatan', 'Seminole', 'Potomac', and 'Catawba'. As observed in previous trials, 'Wonderful White' (18), 'Carolina Beauty' (16), and 'Seminole' (16) were highly susceptible to powdery mildew. Far more cultivars of hybrid crapemyrtle were resistant to powdery mildew than to Cercospora leaf spot. In Louisiana, Holcomb ( 15) also noted similar differences in the sensitivity of cultivars of hybrid crapemyrtle to Cercospora leaf spot. In both the AAES and Louisiana studies, 'Tonto', 'Tuskegee', and 'Tuscarora' were the most Cercospora leaf spot and powdery mildew resistant. A few cultivars of L. indica along with L. fauriei 'Fantasy' also suffered relatively light damage from Cercospora leaf spot and powdery mildew. Surprisingly, compared to powdery mildew, Cercospora leaf spot proved to be an equally if not more, damaging disease on two of the three crapemyrtle taxa. Previously, powdery mildew garnered far more atten- 12 ALABAMA AGRICULTURAL EXPERIMENT STATION tion from professionals than did Cercospora leaf spot. Cultivars resistant to powdery mildew were "found in all three taxa of crapemyrtle. Among the cultivars of L. indica, 'Glendora White' and 'Cherokee' were among the most disease resistant. Hybrid crapemyrtle cultivars highly resistant to powdery mildew were 'Tonto', 'Tuskegee', 'Tuscarora', 'Basham's Party Pink', 'Apalachee', and 'Caddo'. The one cultivar of L.fauriei, 'Fantasy', also suffered little damage from either disease. When horticultural characteristics and disease resistance were both considered, the superior white-flowered cultivars were 'Natchez', 'Sarah's Favorite', and 'Fantasy', while 'Basham's Party Pink', 'Tuscarora', and 'Tuskegee' were the top rated pink-flowered crapemyrtles (3). All of the above crapemyrtles can be easily produced in a nursery or maintained in a landscape without protective fungicide treatments. Those cultivars that were badly damaged by either powdery mildew, Cercospora leaf spot, or in some cases both diseases, may not suffer serious damage in the nursery but would be poor choices for commercial and residential landscapes across Alabama. RESISTANCE OF SELECTED CRAPEMYRTLE CULTIVARS 13 REFERENCES 1. Alfieri, S. A. 1969. Powdery mildew of crapemyrtle. Fla. Dept. of Agric. Cons. Ser. Plant Path. Cir. 83. 2 pp. 2. Alfieri, S. A. 1976. Cercospora leaf spot of crapemyrtle, Lagerstroemia indica. Fla. Dept. of Agric. Cons. Ser. Plant Path Cir. 171. 2 pp. 3. Creech, G., C. Gilliam, G. Keever, A. Hagan, J. Graverman, R. Brantley, and D. Williams. 1999. Crapemyrtle cultivar performance in Alabama. Proc. Southern Nursery Assoc. Res. Conf. 44:489-491. 4. Dirr, M.A. 1998. Manual of Woody Landscape Plants: Their identification, ornamental characteristics, culture, propagation, and uses, 5th Edition. Stipes Publishing Co. Champaign, IL. 1187 pp. 5. Egolf, D. R. 1967. Four new Lagerstroemia indica cultivars (Lythraceae). Baileya 15:7-13. 6. Egolf, D. R. 1970. 'Cherokee ' and 'Seminole'- two new cultivars of Lagerstroemia indica (Lythraceae). Baileya 17:1-5. 7. Egolf, D. R. 1981. 'Muskogee' and 'Natchez' Lagerstroemia. HortScience 16:576-577. 8. Egolf, D. R. 1981. 'Tuscarora' Lagerstroemia. HortScience 16:788-789. 9. Egolf, D. R. 1986. 'Tuskegee' Lagerstroemia. HortScience 21:1078-1080. 10. Egolf, D. R. 1986. 'Acoma', 'Hopi', 'Pecos' , and 'Zumi' Lagerstroemia. HortScience 21:1250-1252. 11. Egolf, D. R. 1987. 'Biloxi', 'Miami' and 'Wichita' Lagerstroemia. HortScience 22:33-338. 12. Egolf, D. R. 1987. 'Apalachee', 'Comanche', ' Lipan', 'Osage', 'Souix', and 'Yuma' Lagerstroemia. HortScience 22:674-677. 14 ALABAMA AGRICULTURAL EXPERIMENT STATION 13. Egolf, D. R. 1990 . .'Caddo' and 'Tonto' Lagerstroemia. HortScience 25:585-587. 14. Egolf, D. R. 1990. 'Choctaw' Lagerstroemia. HortScience 25:992-993. 15. Holcomb, G. E. 1997. Reaction of crapemyrtle cultivars to Cercospora leaf spot and powdery mildew. Biological and Cultural Tests for Control of Plant Diseases. 12:56. 16. Knox, G. W., R. F. Mizell, III, and D. 0 . Chellemi. 1992. Susceptibility of crapemyrtle cultivars to crapemyrtle aphid and powdery mildew. Proc. Southern Nursery Assoc. Res. Conf. 37:340-342. 17. Williams, D., K. Tilt, and S. Valenti-Windsor. 1998. Common Crapemyrtle. Ala. Coop. Ext. Sys. Cir. ANR-1083. 6 pp. 18. Windham, M. T., W. T. Witte, R. J. Sauve, and P. C. Flanagan. 1995. Powdery mildew observations and growth of crapemyrtle in Tennessee. HortScience 30:813. Alabama 's Agricultural Experiment Station AUBURN UNIVERSITY With an agricultural research unit in every major soil area, Auburn University serves the needs of field crop, livestock, forestry, and horticultural producers in each region in Alabama. Every citizen of the state has a stake in this research program, since any advantage from new and more economical ways of producing and handling farm products directly benefits the consuming public. Research Unit Identification @ * Main Agricultural Experiment Station, Auburn. Alabama A&M University '{;:( E. V. Smith Research Center, Shorter. 1. Tennessee Valley Research and Extension Ce nter, Belle Mina. 2. Sand Mountain Researc h and Extension Center. Crossvi lle. 3. North Alabama Horticullure Station, Cu llman . 4. Upper Coastal Plain Research Station, Winfield . 5. Chilton Area Horticulture Station. Clanton. 6. Piedmont Re search Station. Camp Hill. 7. Prattville Experiment Field. Prattville . 8. Black Belt Research and Extension Center, Marion Junction. 9. Lower Coastal Plain Research Station, Camden . 10. Monroeville Experiment Field , Monroeville. 11 . Wiregrass Research and Extension Center. Headland . 12. Brewton Experiment Field , Brewton. 13. Ornamental Horticulture Station. Spring Hill. 14. Gull Coast Research and Extension Center, Fairhope.