缺乏植物多样性马刺队在城市的溃疡损坏

Research from North Carolina State University finds that a lack of plant diversity is a key contributor to the widespread defoliation caused by cankerworms in cities, and highlights the role that increasing diversity can play in limiting future damage.

Fall cankerworms (Alsophila pometaria) are caterpillars that are native to the eastern United States and hatch in early spring. The cankerworms defoliate trees and other plants, eating new leaves as they emerge – which is both unsightly and can ultimately kill the plants.

“We see cankerworms doing more damage to trees in cities than in the wild and examples of widespread cankerworm damage are happening more often,” says Dr. Steve Frank, author of a paper describing the work and an assistant professor of entomology at NC State. “We wanted to know why.”

弗兰克望着城市环境的两个方面that distinguish them from natural environments: the fact that urban environments have less diversity and density of plant life; and the fact that urban areas have more nonnative plant species, such as many ornamental shrubs.

To evaluate the impact of diversity and nonnative species on cankerworm damage, Frank focused on the damage cankerworms did to understory plants – those plants that grow near or under trees.

“I found that plant diversity plays a significant role,” Frank says. “Cankerworms did more damage in simple urban environments, where the understory consisted of only a few shrubs, than they did in more complex environments with greater plant diversity.”

Frank also found a sharp distinction between the impact on native and nonnative plant species.

Native plants were hit particularly hard in simple urban environments. They benefited significantly from complex environments that more closely resembled natural habitat. Nonnative species were largely ignored by cankerworms, regardless of the setting.

“This does not mean that everyone should plant nonnative species,” Frank says. “The take-home message is that we need to take steps to make urban environments more like natural environments in terms of plant diversity.”

The paper, “Bad neighbors: urban habitats increase cankerworm damage to non-host understory plants,” is published online in the journalUrban Ecosystems. The work was supported by the U.S. Department of Agriculture under grant number 2013-02476. Additional support came from the Department of the Interior’s Southeast Climate Science Center, which is based at NC State and provides scientific information to help land managers respond effectively to climate change. An overview of recent NC State research on controlling cankerworm populationsis available here.

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Note to Editors:The study abstract follows.

“糟糕的邻居：城市栖息地增加了溃疡损伤的非宿主林植物”

Author: Steven D. Frank, North Carolina State University

Published: online April 2014,Urban Ecosystems

DOI: 10.1007/s11252-014-0368-x

Abstract:生长在种植的植物中生长的植物或分别般的不同邻居附近的植物经常在更简单的栖息地的植物中经历更少的食草动物。当植物在这些情况下经历更多草食病时，它被称为发球性易感性，并且当食草动物从其优选的植物宿主溢出到邻近的植物时，最常见。溃疡是城市树木的常见害虫，这些树木已经在森林中显示出优于优选的宿主。我发现，城市栖息地，低植物多样性和异国情调的植物的两个共同特征，影响了非宿主林植物的溃疡虫草莓。在城市景观中，我测量了在露天山脉宿主和非宿主树的天然山茱萸树上测量了坎克虫草本。原生山茱萸的草食病在甲虫虫的大于非主持人或公开的树木之下的十倍。在Arboretum，我在简单的景观种植和天然森林中测量了生长在坎虫主持下方的原生和异国情调的植物。原生山茱萸和杜鹃花SPP的关联易感性。当他们在复杂的自然森林中生长时消失，即使坎克虫主持人更加丰富。溃疡虫在实验室实验中始终优选的原生植物物种多于异国情调的同志。 As such, exotic plants experienced very little herbivory regardless of habitat. Herbivorous pests are often more abundant on urban plants than plants in natural habitats. My research shows that, although some plants experience more herbivory when growing near cankerworm hosts, increasing urban habitat complexity could reduce pest damage overall.