Tuesday, May 18, 2010

Downy False Foxglove

The tall plant to the left of the tree is Downy False Foxglove, Aureolaria virginica. As we progress into summer, it will develop attractive fuzzy yellow flowers. I used to see a lot of these around Blue Jay Barrens.

Now this is a more common scene. Deer love this plant and nibble their way right down the stalk. I estimate 90% of the plants are eaten before they have a chance to flower. Most are left with enough leaves to survive, but they won’t resprout and flower this year. Seed production has nearly been stopped.

The eaten plants always show a lot of insect damage. I’m guessing that the stressed plant is more attractive to insects. Unhealthy plants often signal their distress through odor or color. Many insects respond to these signals that a plant is more susceptible to predation and swarm in for a meal.

This particular plant was supporting a large population of little beetles. These were feeding on the cut stalk while others chewed holes in the leaves.

A grasshopper nymph was nibbling on the leaf margins. Shifts in animal populations can dramatically change plant populations. Thirty years ago, deer were only seen occasionally. Now it’s impossible to walk through the woods without seeing multiple deer. It makes me wonder what things will look like as the deer population continues to increase.

3 comments:

  1. hi steve :)

    downy foxglove is something i never see, but it's here in ontario and it's special to us, here's why:

    "Savannah ...Savannah is an ecosystem where scattered trees contribute only 10% to 50% canopy cover. The trees are widely spaced due to competition for moisture and nutrients. In a continuum of ecosystem delineation determined by an increasing requirement for moisture, savannah is the ecosystem that is situated between tallgrass prairie and oak forest. Since the two ecosystems are contiguous, the interdegration between species can be pronounced. As a result of the minimal canopy closure and the resulting abundant sunlight the majority of the understory species are species of the tallgrass prairie. There are however species that are truly associated with savannah. The classic indicator being the False Foxgloves Aureolaria spp." http://www.fes.uwaterloo.ca/resources/ecology/projects/prairie_old/prairie.html

    "Aureolaria virginica ...is endemic to eastern North America (as are congeners A. flava and A. pedicularia)... Aureolaria virginica reported to be parasitic on the roots of Quercus prinus L. and other species of white oaks. ...A. virginica prefers dry-mesic, open oak, woodland slopes with a southern aspect, and tolerates/benefits from some periodic disturbances that maintain a relatively open canopy. ...At the extant Ontario sites, A. virginica is associated with various combinations of black oak (Quercus velutina), red oak (Quercus rubra) and white oak (Quercus alba), with white oak being present at every site and for at least 4 populations, plants are always well within the range of the root spread of a white oak tree..." http://nhic.mnr.gov.on.ca/MNR/nhic/elements/el_report.cfm?elid=153026

    happy you and your barrens support such an interesting (and rare) plant :)

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  2. ps - of course i meant to ask: are your false foxgloves near white oaks, or any other oaks?

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  3. native plant girl - Thanks for the information and the links. I wasn't aware of the association of Aureolaria and savannahs. Most of the plants here are growing close to oaks of some species, but only a couple are near White Oaks. There are a few plants that are growing where I only remember Sugar Maple nearby. I'll have to check these to see if there's also an oak somewhere close.

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