Garlic Mustard: different roles of juveniles and adults?

Dr. Anne Alerding Assistant Professor of Biology

Virginia Military Institute alerdingab@vmi.edu

A diverse forest shows vertical stratification and high species diversity

Stinson et al., 2007 Northeastern Naturalist 14:73–88.

Northeastern forest invasion by garlic mustard decreases plant diversity

# of Garlic mustard plants

Plant Diversity

Invasion decreases vertical stratification (monolayer of garlic mustard)

Garlic mustard kills fungi that help native plants grow

http://www.ctacf.org/index.cfm/2007/3/1/Mycorrhizae-and-the-American-Chestnut-An-Underground-Tale-of-Mystery

ectomycorrhizae endomycorrhizae

Cyanopropenyl glycoside

Flavonoid glycoside

juveniles

adults

Project 1:

Do juveniles and adults produce the same amounts & types of chemicals?

http://www.oardc.ohio-state.edu/weedguide/singlerecord.asp?id=330#

Year 1: Juvenile (vegetative rosette)

Year 2: Adult (reproductive)

Field Juveniles

Field Adults

0

1x108

2x108

3x108

Shoots Roots

Juvenile Adult

Concentration of Peak 1

(A218/g DW)

Juveniles contain more chemicals!

Project 2:

With altered habitat and litter inputs, are animals affected by invasion?

We studied animals that break down litter (detritus):

Detritivores

Springtail – an important detritivore in forest litter

Invaded

Uninvaded

Springtails are more abundant in invaded sites

Springtail abundance

Springtail abundance is higher in less acidic soil

Springtail abundance

Soil pH

Soil pH is less acidic when juveniles increase in abundance

Soil pH

Juvenile Abundance (% of Total Plants)

http://plants.usda.gov

What can YOU do to help?

Eat Garlic Mustard ‘til you burst!

http://www.shakerlakes.org/stewardship/uploaded_images/MustardCover-1-709530.gif