Late to bed

Interesting research from Jason D. Fridley that I may come back to when I take Carole Bergmann’s invasives class in August: Fridley conducted a three-year study comparing congeneric native and non-native shrubs and lianas in the Eastern deciduous forest. The non-natives’ competitive edge didn’t show itself in the spring; both aliens and natives leafed out at about the same time. But the foreign-born Euonymus, Lonicera, Viburnum, and other species dropped their leaves in autumn about a month later than the native woody plants.

Calling all botany geeks

I invite you to participate in the development of a Q&A site for questions about botany. The site would be part of the successful Stack Exchange network, of which Stack Overflow is the flagship.

One of the features of a Stack Exchange site that makes it successful is the liberal awarding of brownie points to users who constructively participate in the site. Jeff Atwood and his team have figured out the alchemy that makes a community-managed site work.

At this point, the proposed Botany site is in the stage of soliciting sample questions. Follow the link below and add your own!

Stack Exchange Q&A site proposal: Botany

Update: The proposal for this Q&A site has been closed, alas.

Winter weeds at Woodend

Five nature fun facts from today’s winter weeds workshop with Stephanie Mason:

  • The generic name for the tickseed sunflowers, Bidens (two-toothed), describes the two-barbed achenes that are typical fruit of the various species.
  • Sensitive Fern (Onoclea sensibilis) is also known as Bead Fern. Look at the spore cases along the fronds in winter to see why.
  • The slender seed pod of Dogbane (Apocynum sp.) looks like a mustard’s silique, but it’s actually a follicle that splits open on one side.
  • Broom Sedge (Andropogon virginicus) is not a sedge, but a grass, and it rather resembles Little Bluestem.
  • A little while ago, I had tumbled to the nomenclatural connection between Cardueline finches and Carduus thistles. But what I didn’t know, as Stephanie explained, is that goldfinches delay breeding into the summer, when thistles are about to set seed. Rather than feeding nestlings insects, as is the norm with songbirds, the parents regurgitate “thistle milk” for their young.

Two into one

Via The Economist, recent research published by Evan Preisser and Joseph Elkinton yields an interesting result to those concerned with the conservation of Eastern Hemlock (Tsuga canadensis) trees. From Virginia to Connecticut, the species has been getting clobbered by an invasive hemipteran, Hemlock Woolly Adelgid (Adelges tsugae), native to Asia. However, comes another sap-sucker, Elongate Hemlock Scale (Fiorinia externa), also invasive, to feed on the hemlock. According to the paper, in experimental infestations, trees inoculated with both bug species fare better than those inoculated with just the adelgid.