Simple rearing experiments were conducted to address two questions relevant to understanding how generalist lepidopteran herbivores interact with alien plants. Yellow-striped armyworm (Spodoptera ornithogalli), luna moth (Actias luna), bagworm (Thyridopteryx ephemeraeformis) and white-marked tussock moth (Orgyia leucostigma) were reared from egg to 5th instar on excised foliage in the laboratory to determine the degree to which highly polyphagous lepidopteran herbivores are physiologically capable of surviving and developing on the suite of alien plants naturalized in the midAtlantic. Actias luna larvae from a single population were similarly reared on a representative of each of the 25 native plant genera recorded as hosts for this species to compare the diet breadth of a local population with that listed over the entire geographic range of the species. With few exceptions, all four generalists either quickly starved or grew at an unsustainably low rate on alien foliage. Actias luna larvae survived for 18 days on only 44% of the native plants recorded as hosts over the entire range of this insect and thrived on only 7%. The data suggest that (1) alien plants are unlikely to produce as much generalist insect biomass as the native plants they replace and (2) Lepidoptera that qualify as generalists when host breadth is considered over their entire geographic range may express a far more specialized diet within local populations. Both of these conclusions support the hypothesis that alien plant invasions may seriously disrupt terrestrial food webs by reducing the insect biomass required by insectivores in higher trophic levels.

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Urban agriculture is regaining popularity as a method of food cultivation to meet the food needs of communities that reside in densely populated areas. Although this method of farming has many benefits, little research has evaluated the potential impacts of practice on the environment, such as water quality resulting from nutrient runoff. To address this gap, this study analyzed runoff water collected from raised beds and small plastic pool container plots with four different types of nutrient management treatments (conventional fertilizer, organic fertilizer, low-compost + organic fertilizer, and high compost). Water samples were collected from each of the raised bed and container plots once per month, weather permitting, and analyzed for pH, conductivity, color, turbidity, nitrate-nitrogen, ammonia-nitrogen, total phosphorus, and potassium. Although there were some significant differences between the raised beds and container plots, they did not translate to meaningful differences in water quality for most variables measured, except for nitrate-nitrogen. The conventional fertilizer treatment demonstrated greater or more variable nutrient leaching than the other nutrient management treatments. This result suggests an opportunity for improved nutrient management by urban farmers to reduce nutrient leaching. Sampling time was found to have a significant impact on runoff water quality, which could be attributed to varying precipitation rates between samplings and timing of sampling in relation to compost and fertilizer applications, and crop production cycles.