American Nurseryman -Jan 2012

Conifers for the Southeast Able to stand up to heat and humidity conifers suitable for the Southern states merit serious consideration both for landscape use and for growers inventories By John M Ruter N ot much attention has been paid to the use of conifers in the Southeast and thats a shame Back in the mid 1990s American Nurseryman ran a series of articles utilizing conifer experts from around the country but only one of those experts was from the southeastern United States In the Coastal Plain region conifers are often thought of as pine trees for forestry or junipers for landscaping thats it Due to a lack of information on conifer adaptability for the lower South in 1996 I started collecting germplasm for an evaluation project at The University of Georgia campus in Tifton Ga The Tifton campus is 64 miles north of the Florida border in south central Georgia The station is located in USDA Hardiness Zone 8a and Tifton averages about 100 days per year at or above 90 F My goal was to determine which conifers are best suited for this region The initial plantings were installed in January 1997 Individual plants were planted 125 feet within rows with 20 feet between rows Composted pecan shells were applied as mulch and drip irrigation with an emitter at each plant was installed Fertilizer is applied at the rate of 50 lbs N A in the spring and 25 lbs N A in August using 16 4 8 soluble granular fertilizer with micronutrients The pH of the site at time of planting was 55 Weeds are controlled with preemergent applications of simazine and oryzalin in February Abies nordmanniana Photos courtesy of John M Ruter and September Glyphosate is applied as needed as a post emergent herbicide Based on observations throughout the multiyear study I can recommend a number of conifers that deserve a greater presence in the landscapes of the Southeast Conifers for consideration Abies fi rma or Momi fi r from southern Japan is the only true fi r that can grow across the entire Southeastern region Momi fi r has good resistance to Phytophthora root rot and is being used as an understock to evaluate other species in the South In zones 6 and 7a A homolepis and A nordmanniana perform well For conifer enthusiasts along the Gulf Coast Afrocarpus falcatus has fi nely textured foliage and makes a large shrub or small tree New growth is damaged below 18 F but there has been no stem dieback in Tifton The Parana pine or Araucaria angustifolia has been a pleasant surprise in Georgia performing well in Tifton and next to the conservatory at the Atlanta Botanical Garden Hybrids between this species and the Monkey Puzzle tree A araucana are being evaluated for resistance to root rot A bidwillii has also grown well with minimal winter damage to shoot tips in Tifton In the Piedmont and mountain regions of the South zones 6b and 7 incense cedar Calocedrus decurrens performs very well but old trees 14 JANUARY 2012 American Nurseryman www amerinursery com