Life Sciences Commons^™

Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson

Master's Theses

It is widely accepted that allelopathy is not only significant, but more or less singular, in the inhibition of understory vegetation in California Eucalyptus globulus (blue gum) plantations. However, there is no published documentation of allelopathy by blue gums against California native species. Here, we present evidence that germination and early seedling growth of five California native species are not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels. In the greenhouse, seeds were germinated in field-collected soil from mature blue gum plantations and the adjacent native, coastal scrub communities. In petri plates, seeds …

Monarch Butterfly (Danaus Plexippus) Tree Preference And Intersite Movement At California Overwintering Sites, Jessica Lynn Griffiths

Master's Theses

Managing Monarch butterfly overwintering groves: making room among the eucalyptus

Proper management and conservation of the coastal California overwintering sites used by western Monarch butterflies (Danaus plexippus L.) is critical for continued use of these sites by monarchs. Many management efforts are currently concentrating on eucalyptus-only sites because of the prevailing notion that monarchs prefer eucalyptus over native tree species. Yet, whether a preference exists or not has never been tested. Herein, we test the “eucalyptus preference” hypothesis with data from five overwintering sites comprised of blue gum eucalyptus (Eucalyptus globulus) and at least one other native tree …