Systematic studies in crataegus (rosaceae)

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My research deals with one of the most important woody plants in North America - hawthorn(Crataegus). Hawthorns automatically become important because they are such frequently abundant, even sometimes dominant species, in natural ecosystems. There are well over a 100 species of them in North America, more than for any woody plant. Some of the roles of hawthorn in nature are: creating animal habitat (cover, nesting sites, breeding grounds for many species); enormous provision of pollen and nectar at flowering time; like supply of fruit for birds, small mammals, also deer and bear. Hawthorns also have direct human use in  medicine e.g., for hypertension,  hedging, pomology and ornamental horticulture. Slight to major differences found between species shows up in their differing habitats and varied ecology but needs to be made explicit, as is done by my studies, which describe new species of hawthorn discovered by myself and co-worker O'Kennon and also place these and already known species in a scheme of classification which is critical to an ordered understanding of the subject. Lacking any exact understanding of the particular hawthorn species involved, ecological studies involving them become stymied and conservation of rare species impossible. It is, therefore, essential that this work be brought before the biological public.