1. Naval Air Station Patuxent River Kudzu Control Jacqueline Smith CIV NAVFAC Washington, Environmental Dept jacqueline.c.smith@navy.mil NMFWA Invasive Species Working Group March 2014

2. NAS Patuxent River The NAS Patuxent River Complex is in St. Mary’s County in Southern Maryland. The Main Base encompasses ~6,690 acres. The naval air station complex also includes: Webster Field Annex, Naval Recreation Center Solomons, Bloodsworth Island Range, and several theodolite antenna sites.

3. NAS Patuxent River Invasive Plant Surveys A comprehensive survey and mapping was begun in 2001-2003 on the Main Base and was completed in 2007- 2008 on the Main Base, NRC Solomons, and Webster Field. Twenty-seven species totaling 527 acres of invasive infestation were mapped. Sericea lespedeza, phragmites, and kudzu were the most abundant individual species mapped. Common NameScientific NameAcres Mixed Species Autumn olive Japanese honeysuckle Privet Rose, non-native Wineberry Elaeagnus umbellata Lonicera japonica Ligustrum spp. Rosa multiflora Rubus phoenicolasius 408.65 Sericea lespedezaLespedeza cuneata70.00 PhragmitesPhragmites australis31.87 KudzuPueraria montana20.61 Japanese stiltgrass Small carpgrass Microstegium vimineum Arthraxon hispidus 2.32 Tree-of-heavenAilanthus altissima1.22 English ivyHedera helix0.53 Japanese knotweed Polygonum cuspidatum 0.33 BambooPhyllostachys spp.0.19 Callery pearPyrus calleryana0.02 Miscellaneous Species Asiatic dayflower Canadian thistle Mile-a-minute Mimosa Bush honeysuckle Commelina communis Cirsium arvense Polygonum perfoliatum Albizia julibrissin Lonicera spp. 0.45 Total 527.19 Bamboo Bradford Pear English Ivy Japanese Knotweed Japanese Stiltgrass Kudzu Miscellaneous Species Mixed Species Phragmites Sericea Lespedeza Tree of Heaven Invasive Species

4. NAS Patuxent River Kudzu Areas

5. Airfield Clear Zone Kudzu

6. Kudzu treatments were conducted in 2000, 2002, and 2004 using a 2% glyphosate solution for foliar treatments and 100% glyphosate for the cut stumps. Another treatment was conducted in 2007 again using a foliar application of glyphosate. No treatments were conducted in 2008. By 2009 kudzu expanded to more than 20 acres. Early Treatments 07/13/2006

7. Successful Treatment A focused approach was adopted, including using two broadleaf-specific herbicides, Garlon and Transline. Treatments consisted of: Cutting vines from the trees and foliar spray in the fall of 2009 An early summer herbicide application when leaves had fully leafed out in 2010 Follow up late fall spot treatment targeting any re-growth or missed foliage in 2010 Annual growing season treatments and mop up conducted from 2011 – 2013.

8. 2009 Nearly 100 % cover kudzu No visible native vegetation 2010 Less than 25% cover kudzu Native grasses and forbs began to recover 2011 Less than 1% cover kudzu Native grasses and forbs on up to 75% of site

9. Persistence and Knowledge were Key to Success Control of invasive species populations can reach 95% within 3 years, but the additional 1-2 years are often needed to ensure complete control. Without adequate follow-up treatments, the initial investment and effort are wasted. Using selective herbicides that limit damage to non-target species increases native community restoration. From ThisTo This