Kenneth D. McCrea

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The allocations of biomass, N, P, and K were determined by standard methods in goldenrod ramets (1) parasitized by dipteran and lepidopterous gallmakers, (2) from fertilized and unfertilized plots, and (3) whose rhizome connections to their parental clone were severed. The presence of ball galls and their larvae increased allocation to stem but decreased(More)
Larvae of the tephritid fly Eurosta solidaginis induce ball-shaped galls on the stem of tall goldenrod, Solidago altissima. Survival probability depends on gall size; in small galls the larva is vulnerable to parasitoid oviposition, whereas larvae in large galls are more frequently eaten by avian predators. Fly populations from 20 natural old fields in(More)
Despite the widespread occurrence of plant-gallmaker interactions, little is known about the actual mechanisms of gall formation. To further characterize this type of parasite-host interaction, the mechanism of gall formation in Solidago altissima, tall goldenrod, by the larva of the tephritid fly Eurosta solidaginis was studied. Proteins produced by galled(More)
The relationship between nutrient element concentration and stream discharge during storm events was studied in a nutrient-rich first order stream. Stream concentrations of NO3-N, phosphate-P, Ca, and Mg were determined during the course of and following thunderstorms. Nutrient element trajectories were constructed for the elements monitored and some(More)
Under a restricted set of conditions, predator-prey or parasite-host systems may exhibit an escalating arms race over several generations that is not coevolutionary. Preconditions for such a process include high correlation between prey/host quality and defensive capability, and phenotypic plasticity in predator/parasite-counter defenses that responds to(More)
Ramets from six Solidago altissima clones of known resistance to the stem gallmaker Eurosta solidaginis were grown with and without supplemental nutrients. In a greenhouse experiment, mated female Eurosta were allowed to oviposit in ramets that were subsequently grown through flowering and then harvested to determine biomass allocation. Supplemental(More)
Armstrong (1982, 1983) predicted that all ramets within a clone should have the same ratio of biomass allocation to sexual reproduction versus vegetative growth. He presented data (1984) that he interpreted as showing that Solidago altissima ramets in a clone do have the predicted constant allocation ratio. Reanalysis of his methods shows that this(More)
Three ramet clones of Solidago altissima were grown under greenhouse conditions to determine the effects of varying levels of attack by the goldenrod ball gallmaker (Eurosta solidaginis) on biomass allocation, leaf senescence rate and rhizome connections among ramets. The results, examined at both the individual ramet level and the clone level, showed that(More)
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