Road Survey of the Invasive Tree-of-Heaven (Ailanthus altissima) in Virginia

Abstract

Tree-of-heaven is an invasive, nonnative species that invades newly disturbed areas and forms large monospecific stands. It was surveyed from a vehicle along 5,175 km of roads in Virginia in 2004, 2005, 2010, and 2011. Fifty-eight percent of every 1.6-km road segment had at least one tree-of-heaven. Mean density of tree-of-heaven throughout the roads surveyed in Virginia was 39 km−1. The interaction between road classification (interstate, primary, and secondary) and physiographic region (mountain, piedmont, and tidewater) was significant; consequently, the density of tree-of-heaven along the different road classifications depended on the effect of the physiographic region and vice versa. Tree-of-heaven was fairly evenly distributed throughout Virginia ranging from 39 to 78% of 1.6-km road segments infested, but had a greater variation in density. Current areas with low densities could increase in density in the future. The highest density of tree-of-heaven was along interstate highways in the mountains (85 km−1), followed by the tidewater (63 km−1), and piedmont (46 km−1) regions. Primary roads had a moderate density of tree-of-heaven with a range of 24 to 36 km−1. Secondary roads had lower densities with 12 km−1and 41 km−1in the tidewater and mountain regions, respectively. Tree-of-heaven spreads primarily by wind-dispersed seeds from female trees, and populations bordering roadsides could serve as seed sources for further local and landscape spread.

Citizen Science as a Tool in Biological Recording—A Case Study of Ailanthus altissima (Mill.) Swingle

“…Invasive species biological recording, mapping, and monitoring are prerequisites for successful biological invasion risk management [31][32][33] and to prevent invasive species expansion into large areas, where eradication becomes very difficult and costly [1]. Among invasive plants, trees are generally easiest to map because of their size [34], although there is currently no methodical, reasonably priced protocol for the estimation of tree invasions that can be used in invasive species management or scientific research [35].…”

Seasonal effects on mortality rates and resprouting of stems treated with glyphosate in the invasive tree of heaven (Ailanthus altissima(Mill.) Swingle)

“…Even root fragments 1-cm long and a few mm wide are able to produce new suckers (Inverso & Bellani, 1991). In addition, main highways and railways, where Ailanthus commonly occurs, may act as a substantial source of seed to neighbouring natural and semi-natural areas, thus increasing its rate of spread (Aldrich et al, 2010;McAvoy, Snyder, Johnson, Salom, & Kok, 2012). Furthermore, in invaded environments, Ailanthus releases allelopathic compounds that may affect competitive dynamics with the native co-occurring species, especially during the seedling stage (Gómez-Aparicio & Canham, 2008), when competition for resources is generally higher.…”

Brown Marmorated Stink Bug (Hemiptera: Pentatomidae) Infestations in Tree Borders and Subsequent Patterns of Abundance in Soybean Fields

“…Additional studies have shown that nonmanaged forested areas, in particular, are thought to be important season-long reservoirs for dispersal of H. halys to agricultural crops (Bakken et al 2015). In Virginia, we have observed particularly high densities of H. halys on the invasive tree of heaven, Ailanthus altissima Mill., which has become the most dominant tree species along the edges of forests and roadways in Virginia (McAvoy et al 2012). Moreover, based on annual surveys of soybeans across Virginia from 2011 to 2012, the soybean fields having highest H. halys pest pressure were typically bordered by woods containing A. altissima.…”