Herbicide Transfer through Clonal Milkweed

In this study I propose to use common Milkweed as a study system to understand the impact of clonality and group survival. By intentionally adding a pathogen, such as an herbicide, the spread of the negative effects can be witnessed in a clonally connected plant. The goal of this experiment is to see how far the pathogens travel in a patch, how long it takes for other plants to die, and if there is any preferential sharing.

Herbicide will be used as a proxy for connectedness and physiological integration. In June, fieldwork will take place at Blandy Experimental Farm. Ten meter transects will be created in patches of Milkweed. One plant every four feet will be given the herbicide, which will be painted onto the leaves. Observations will then take place for each plant along the transect. Plant health observations will be measured using qualitative measures for spottiness and wilting, and quantitative data detailing nutrient content using a field spectro-radiometer. These measurements will be taken every 12 hours. Connected plants will theoretically decline in plant health.

This experiment is important as one of the most common habitats for Milkweed is by the side of agricultural fields. If agricultural pesticide runoff is present near Milkweed, it has the potential to kill off an entire patch of clonally connected Milkweed plants. Currently, with the help of two other undergraduates, a trial run of this experiment is being run in the greenhouse to fine-tune the protocol before bringing it out into the field. Control plants that are not connected are used to demonstrate if water transfer of the herbicide is happening in the soil as opposed to through