2017 update: Aphid addition and exclusion

Aphids on an Echinacea leaf

This summer Team Echinacea continued adding and excluding aphids to plants in the experiment that Katherine Muller started. In 2011, Katherine Muller designated a sample of 100 Echinacea plants in experimental plot 1 for aphid addition or removal. The presence or absence of these aphids was maintained by team members once a week in the summer of 2017, for a total of 7 weeks from early July to mid August. We maintained addition on 31 plants and exclusion on 30, for a total of 61 plants. Will Reed set up a data entry system where we could enter data twice from the paper sheets and check for data-entry errors. In early October, Lea Richardson and Tracie Hayes recorded signs of senescence in the leaves of treatment plants. This data can be combined with data from our common garden measuring data to explore the richness of the Echinacea-aphid relationship.

Aphis echinaceae is a specialist aphid that is found only on Echinacea angustifolia. Read more about this experiment.

Start year: 2011

Location: Experimental Plot 1

Overlaps with: Phenology and fitness in P1

Data collected:

• Aphid counts for each treatment plant on each observation day, on paper
• Aphid counts recorded in csvs, on the teamEchinacea2017 dropbox
• Leaf senescence data, recorded on paper
• Initial and final assessment of aphid counts on treatment plants, recorded on paper
• Aphid counts also included in p1 measuring data

Products:

• 2016 paper by Katherine Muller and Stuart on aphids and foliar herbivory damage on Echinacea
• 2015 paper by Ruth Shaw and Stuart on fitness and demographic consequences of aphid loads
• 2015 poster by Daniel Brown and Kyle Silverhus (Lake Forest College) on achene and seed set differences on treatment plants

You can read more about the aphid addition and exclusion experiment, as well as links to prior flog entries mentioning the experiment, on the background page for this experiment.