Cankerworms may have been responsible for a large proportion of the herbivory we measured.
It is possible that arthropod predators showed a strong numerical response to the cankerworm outbreak, which may have been more common within exclosures given the marginally greater spring leaf damage on exclosure trees.
Adult cankerworms emerge in late fall to mate, and the wingless females oviposit eggs at the base of small twigs of nearby vegetation.
0 m in height) located either under a mature box elder, under a mature conspecific, or in the open and relatively isolated from other trees that could serve as sources of cankerworms.
Cottonwoods under box elder supported 30X more cankerworms per shoot than trees in the open, with cottonwoods under conspecifics showing statistically intermediate cankerworm densities (Kruskal-Wallis H = 13.
Potted cottonwoods placed directly under box elder always acquired the most cankerworms, and typically supported nearly 3 X more larvae than trees placed only 1 m from the box elder canopy.
The first goal of this paper is to document an example of associational susceptibility using the hosts of a common forest pest, the fall cankerworm (Alsophila pometaria).
The timing of late instar cankerworm dispersal is heavily dependent on box elder infestation levels, which varied considerably from tree to tree.
The experiment was started on 19 April 1996, before cankerworm egg hatch began.
A second experiment was performed to determine how cankerworm attack on cottonwood decreases as a function of distance from "source" box elders.
Bacillus thuringiensis, for early stage lepidopteron pests, such as Cankerworms
, Eastern Tent Caterpillars, and Forest Tent Caterpillars).